1656:. The issue in question is calls between Americans and foreigners. The NSA is not authorized to tap Americans' conversations without a warrant—but the Internet, and specifically VoIP does not draw as clear a line to the location of a caller or a call's recipient as the traditional phone system does. As VoIP's low cost and flexibility convinces more and more organizations to adopt the technology, surveillance for law enforcement agencies becomes more difficult. VoIP technology has also increased federal security concerns because VoIP and similar technologies have made it more difficult for the government to determine where a target is physically located when communications are being intercepted, and that creates a whole set of new legal challenges.
1600:(USFK) members residing on USFK bases threatened to block off access to VoIP services used by USFK members as an economical way to keep in contact with their families in the United States, on the grounds that the service members' VoIP providers were not registered. A compromise was reached between USFK and Korean telecommunications officials in January 2007, wherein USFK service members arriving in Korea before June 1, 2007, and subscribing to the ISP services provided on base could continue to use their US-based VoIP subscription, but later arrivals are required to use a Korean-based VoIP provider, which by contract will offer pricing similar to the flat rates offered by US VoIP providers.
1055:(LCR) challenges to reach its destination if the number is routed to a mobile phone number on a traditional mobile carrier. LCR is based on checking the destination of each telephone call as it is made, and then sending the call via the network that will cost the customer the least. This rating is subject to some debate given the complexity of call routing created by number portability. With MNP in place, LCR providers can no longer rely on using the network root prefix to determine how to route a call. Instead, they must now determine the actual network of every number before routing the call.
1044:(MNP) also impact VoIP business. Number portability is a service that allows a subscriber to select a new telephone carrier without requiring a new number to be issued. Typically, it is the responsibility of the former carrier to "map" the old number to the undisclosed number assigned by the new carrier. This is achieved by maintaining a database of numbers. A dialed number is initially received by the original carrier and quickly rerouted to the new carrier. Multiple porting references must be maintained even if the subscriber returns to the original carrier. The
601:
1455:, the treatment of VoIP service providers is a decision for each national telecommunications regulator, which must use competition law to define relevant national markets and then determine whether any service provider on those national markets has "significant market power" (and so should be subject to certain obligations). A general distinction is usually made between VoIP services that function over managed networks (via broadband connections) and VoIP services that function over unmanaged networks (essentially, the Internet).
5817:
809:(VCI) for voice over IP has the potential to reduce latency on shared connections. ATM's potential for latency reduction is greatest on slow links because worst-case latency decreases with increasing link speed. A full-size (1500 byte) Ethernet frame takes 94 ms to transmit at 128 kbit/s but only 8 ms at 1.5 Mbit/s. If this is the bottleneck link, this latency is probably small enough to ensure good VoIP performance without MTU reductions or multiple ATM VCs. The latest generations of DSL,
1374:
786:(MOS) and R factors and configuration information related to the jitter buffer. VoIP metrics reports are exchanged between IP endpoints on an occasional basis during a call, and an end of call message sent via SIP RTCP summary report or one of the other signaling protocol extensions. VoIP metrics reports are intended to support real-time feedback related to QoS problems, the exchange of information between the endpoints for improved call quality calculation and a variety of other applications.
5341:
5327:
6888:
931:
6898:
6877:
5807:
6908:
1289:. Though many consumer VoIP solutions do not support encryption of the signaling path or the media, securing a VoIP phone is conceptually easier to implement using VoIP than on traditional telephone circuits. A result of the lack of widespread support for encryption is that it is relatively easy to eavesdrop on VoIP calls when access to the data network is possible. Free open-source solutions, such as
1479:, it is illegal to provide or use unauthorized VoIP services, to the extent that web sites of unlicensed VoIP providers have been blocked. Violations may be punished with fines of 50,000 Omani Rial (about 130,317 US dollars), a two-year prison sentence or both. In 2009, police raided 121 Internet cafes throughout the country and arrested 212 people for using or providing VoIP services.
739:. This suggests continually estimating the mean delay and its standard deviation and setting the playout delay so that only packets delayed more than several standard deviations above the mean will arrive too late to be useful. In practice, the variance in latency of many Internet paths is dominated by a small number (often one) of relatively slow and congested
1592:, only providers registered with the government are authorized to offer VoIP services. Unlike many VoIP providers, most of whom offer flat rates, Korean VoIP services are generally metered and charged at rates similar to terrestrial calling. Foreign VoIP providers encounter high barriers to government registration. This issue came to a head in 2006 when
1114:. The VoIP E911 emergency-calling system associates a physical address with the calling party's telephone number. All VoIP providers that provide access to the public switched telephone network are required to implement E911, a service for which the subscriber may be charged. "VoIP providers may not allow customers to opt-out of 911 service." The
620:
bare metal infrastructure or IoT devices. With some solutions, such as 3CX, companies can attempt to blend the benefits of hosted and private on-premises systems by implementing their own private solution but within an external environment. Examples can include data center collocation services, public cloud, or private cloud locations.
1419:, where the government is nationalizing telecommunication service, it is a criminal offense to offer services using VoIP. The country has installed firewalls to prevent international calls from being made using VoIP. These measures were taken after the popularity of VoIP reduced the income generated by the state-owned
528:. Rather than closed architectures, these devices rely on standard interfaces. VoIP devices have simple, intuitive user interfaces, so users can often make simple system configuration changes. Dual-mode phones enable users to continue their conversations as they move between an outside cellular service and an internal
208:, built closed networks for private user bases, offering the benefit of free calls and convenience while potentially charging for access to other communication networks, such as the PSTN. This limited the freedom of users to mix-and-match third-party hardware and software. Third-generation providers, such as
1103:(ITSP) knows only that a particular user's equipment is active. Service providers often provide emergency response services by agreement with the user who registers a physical location and agrees that, if an emergency number is called from the IP device, emergency services are provided to that address only.
1296:
Government and military organizations use various security measures to protect VoIP traffic, such as voice over secure IP (VoSIP), secure voice over IP (SVoIP), and secure voice over secure IP (SVoSIP). The distinction lies in whether encryption is applied in the telephone endpoint or in the network.
987:
Softswitch) works in cooperation with a media gateway (aka IP Business
Gateway) and connects the digital media stream, so as to complete the path for voice and data. Gateways include interfaces for connecting to standard PSTN networks. Ethernet interfaces are also included in the modern systems which
611:
In the case of a private VoIP system, the primary telephony system itself is located within the private infrastructure of the end-user organization. Usually, the system will be deployed on-premises at a site within the direct control of the organization. This can provide numerous benefits in terms of
695:
VoIP endpoints usually have to wait for the completion of transmission of previous packets before new data may be sent. Although it is possible to preempt (abort) a less important packet in mid-transmission, this is not commonly done, especially on high-speed links where transmission times are short
1058:
Therefore, VoIP solutions also need to handle MNP when routing a voice call. In countries without a central database, like the UK, it may be necessary to query the mobile network about which home network a mobile phone number belongs to. As the popularity of VoIP increases in the enterprise markets
1071:
has a direct relationship between a telephone number and a physical location, which is maintained by the telephone company and available to emergency responders via the national emergency response service centers in form of emergency subscriber lists. When an emergency call is received by a center
554:
In general, the provision of VoIP telephony systems to organizational or individual users can be divided into two primary delivery methods: private or on-premises solutions, or externally hosted solutions delivered by third-party providers. On-premises delivery methods are more akin to the classic
691:
not TCP because recovering from congestion through retransmission usually entails too much latency. So QoS mechanisms can avoid the undesirable loss of VoIP packets by immediately transmitting them ahead of any queued bulk traffic on the same link, even when the link is congested by bulk traffic.
619:
Private VoIP systems can be physical hardware PBX appliances, converged with other infrastructure, or they can be deployed as software applications. Generally, the latter two options will be in the form of a separate virtualized appliance. However, in some scenarios, these systems are deployed on
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service without special request, provide for customer location updates, clearly disclose any limitations on their E-911 functionality to their consumers, obtain affirmative acknowledgements of these disclosures from all consumers, and may not allow their customers to opt-out of 911 service. VoIP
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or locally generated power. Some VoIP service providers use customer premises equipment (e.g., cable modems) with battery-backed power supplies to assure uninterrupted service for up to several hours in case of local power failures. Such battery-backed devices typically are designed for use with
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which provide direct current to power most basic analog handsets independently of locally available electrical power. The susceptibility of phone service to power failures is a common problem even with traditional analog service where customers purchase telephone units that operate with wireless
651:
systems; a circuit switched system of insufficient capacity will refuse new connections while carrying the remainder without impairment, while the quality of real-time data such as telephone conversations on packet-switched networks degrades dramatically. Therefore, VoIP implementations may face
1980:
announces and launches its desktop conferencing product
Communique, which includes VoIP and video. The company is credited with developing the first generation of commercial, US-based VoIP, Internet media streaming and real-time Internet telephony/collaborative software and standards that would
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may appear as part of an upstream IP PBX. On mobile devices, e.g., a 3G handset or USB wireless broadband adapter, the IP address has no relationship with any physical location known to the telephony service provider, since a mobile user could be anywhere in a region with network coverage, even
539:
services that treat all communications—phone calls, faxes, voice mail, e-mail, web conferences, and more—as discrete units that can all be delivered via any means and to any handset, including cellphones. Two kinds of service providers are operating in this space: one set is focused on VoIP for
642:
Communication on the IP network is perceived as less reliable in contrast to the circuit-switched public telephone network because it does not provide a network-based mechanism to ensure that data packets are not lost, and are delivered in sequential order. It is a best-effort network without
1571:
In India no
Separate Numbering Scheme is provided to the Internet Telephony. Presently the 10 digit Numbering allocation based on E.164 is permitted to the Fixed Telephony, GSM, CDMA wireless service. For Internet Telephony, the numbering scheme shall only conform to IP addressing Scheme of
1816:(SIP) gained widespread attention. In the early 2000s, the proliferation of high-bandwidth always-on Internet connections to residential dwellings and businesses, spawned an industry of Internet telephony service providers (ITSPs). The development of open-source telephony software, such as
432:
781:
is generated by an VoIP phone or gateway during a live call and contains information on packet loss rate, packet discard rate (because of jitter), packet loss/discard burst metrics (burst length/density, gap length/density), network delay, end system delay, signal/noise/echo level,
1458:
The relevant EU Directive is not clearly drafted concerning obligations that can exist independently of market power (e.g., the obligation to offer access to emergency calls), and it is impossible to say definitively whether VoIP service providers of either type are bound by them.
663:
By default, network routers handle traffic on a first-come, first-served basis. Fixed delays cannot be controlled as they are caused by the physical distance the packets travel. They are especially problematic when satellite circuits are involved because of the long distance to a
616:), cost scalability, and ensuring privacy and security of communications traffic. However, the responsibility for ensuring that the VoIP system remains performant and resilient is predominantly vested in the end-user organization. This is not the case with a Hosted VoIP solution.
2443:
Voice over IP (VOIP) uses the
Internet Protocol (IP) to transmit voice as packets over an IP network. ...in the Internet, anyone can capture the packets meant for someone else. Some security can be provided by using encryption and tunneling. The common tunneling protocol used is
591:
Endpoints, such as VoIP telephones or softphone applications (apps running on a computer or mobile device), will connect to the VoIP service remotely. These connections typically take place over public internet links, such as local fixed WAN breakout or mobile carrier service.
1145:
protocol. The T.38 protocol is designed to compensate for the differences between traditional packet-less communications over analog lines and packet-based transmissions which are the basis for IP communications. The fax machine may be a standard device connected to an
1230:
attacks, harvest customer data, record conversations, and compromise voicemail messages. Compromised VoIP user account or session credentials may enable an attacker to incur substantial charges from third-party services, such as long-distance or international calling.
1153:
Some newer high-end fax machines have built-in T.38 capabilities which are connected directly to a network switch or router. In T.38 each packet contains a portion of the data stream sent in the previous packet. Two successive packets have to be lost to actually lose
349:, one of the first VoIP call signaling and control protocols that found widespread implementation. Since the development of newer, less complex protocols such as MGCP and SIP, H.323 deployments are increasingly limited to carrying existing long-haul network traffic.
634:, private networks such as MPLS and SD-WAN, or via private SBCs (Session Border Controllers). While exceptions and private peering options do exist, it is generally uncommon for those private connectivity methods to be provided by Hosted or Cloud VoIP providers.
1048:(FCC) mandates carrier compliance with these consumer-protection stipulations. In November 2007, the FCC in the United States released an order extending number portability obligations to interconnected VoIP providers and carriers that support VoIP providers.
523:
VoIP allows both voice and data communications to be run over a single network, which can significantly reduce infrastructure costs. The prices of extensions on VoIP are lower than for PBX and key systems. VoIP switches may run on commodity hardware, such as
824:
ATM has substantial header overhead: 5/53 = 9.4%, roughly twice the total header overhead of a 1500 byte
Ethernet frame. This "ATM tax" is incurred by every DSL user whether or not they take advantage of multiple virtual circuits – and few can.
1787:
for commercial traffic, IP telephony was tested and deemed infeasible for commercial use until the introduction of VocalChat in the early 1990s and then in Feb 1995 the official release of
Internet Phone (or iPhone for short) commercial software by
479:
application software installed on a networked computer that is equipped with a microphone and speaker, or headset. The application typically presents a dial pad and display field to the user to operate the application by mouse clicks or keyboard
546:, which originally marketed itself as a service among friends, has begun to cater to businesses, providing free-of-charge connections between any users on the Skype network and connecting to and from ordinary PSTN telephones for a charge.
1187:
analog handsets. Some VoIP service providers implement services to route calls to other telephone services of the subscriber, such a cellular phone, in the event that the customer's network device is inaccessible to terminate the call.
1782:
In the two decades following the 1974 demo, various forms of packet telephony were developed and industry interest groups formed to support the new technologies. Following the termination of the ARPANET project, and expansion of the
511:
Because of the bandwidth efficiency and low costs that VoIP technology can provide, businesses are migrating from traditional copper-wire telephone systems to VoIP systems to reduce their monthly phone costs. In 2008, 80% of all new
1608:
In the United States, the FCC requires all interconnected VoIP service providers to comply with requirements comparable to those for traditional telecommunications service providers. VoIP operators in the US are required to support
1800:, and followed by other VoIP infrastructure components such as telephony gateways and switching servers. Soon after it became an established area of interest in commercial labs of the major IT concerns, notably at AT&T, where
1075:
In IP telephony, no such direct link between location and communications end point exists. Even a provider having wired infrastructure, such as a DSL provider, may know only the approximate location of the device, based on the
730:
Although jitter is a random variable, it is the sum of several other random variables that are at least somewhat independent: the individual queuing delays of the routers along the
Internet path in question. Motivated by the
447:. Many offer unlimited domestic calling and sometimes international calls for a flat monthly subscription fee. Phone calls between subscribers of the same provider are usually free when flat-fee service is not available.
1547:
inside India. This effectively means that people who have PCs can use them to make a VoIP call to other computers but not to a normal phone number. Foreign-based VoIP server services are illegal to use in India.
1672:
and other researchers were motivated by a desire for a higher degree of circuit redundancy and network availability in the face of infrastructure failures than was possible in the circuit-switched networks in
319:– Implementing access control, verifying the identity of other participants (computers or people), and encrypting data to protect the privacy and integrity of the media contents and/or the control messages.
1507:
were allowed. In
January 2018, internet service providers in UAE blocked all VoIP apps, including Skype, but permitting only 2 government-approved VoIP apps (C’ME and BOTIM). In opposition, a petition on
647:(QoS) guarantees. Voice, and all other data, travels in packets over IP networks with fixed maximum capacity. This system may be more prone to data loss in the presence of congestion than traditional
1579:
The
Internet Service Licensee is not permitted to have PSTN/PLMN connectivity. Voice communication to and from a telephone connected to PSTN/PLMN and following E.164 numbering is prohibited in India.
1150:(ATA), or it may be a software application or dedicated network device operating via an Ethernet interface. Originally, T.38 was designed to use UDP or TCP transmission methods across an IP network.
1360:
VoIP has drastically reduced the cost of communication by sharing network infrastructure between data and voice. A single broadband connection has the ability to transmit multiple telephone calls.
258:
A variety of functions are needed to implement VoIP communication. Some protocols perform multiple functions, while others perform only a few and must be used in concert. These functions include:
204:
Early providers of voice-over-IP services used business models and offered technical solutions that mirrored the architecture of the legacy telephone network. Second-generation providers, such as
2138:
released in August 2003. This was the creation of Niklas
Zennström and Janus Friis, in cooperation with four Estonian developers. It quickly became a popular program that helped democratize VoIP.
1561:
Any device / Adapter conforming to standards of International agencies like ITU, IETF etc. connected to ISP node with static IP address to similar device / Adapter; within or outside India.
469:
connects to the network and implements the electronics and firmware to operate a conventional analog telephone attached through a modular phone jack. Some residential Internet gateways and
4585:
1134:
over VoIP networks is sometimes referred to as Fax over IP (FoIP). Transmission of fax documents was problematic in early VoIP implementations, as most voice digitization and compression
4829:
3785:
905:
The quality of voice transmission is characterized by several metrics that may be monitored by network elements and by the user agent hardware or software. Such metrics include network
443:, by which subscribers place and receive telephone calls in much the same manner as they would via the PSTN. Full-service VoIP phone companies provide inbound and outbound service with
892:). G.hn provides QoS by means of Contention-Free Transmission Opportunities (CFTXOPs) which are allocated to flows (such as a VoIP call) that require QoS and which have negotiated a
287:– Performing registration (advertising one's presence and contact information) and discovery (locating someone and obtaining their contact information), dialing (including reporting
5052:
715:
along a given network path due to competition from other users for the same transmission links. VoIP receivers accommodate this variation by storing incoming packets briefly in a
5205:
vom Treffen der IETF-Codec-Arbeitsgruppe auf der Konferenz IETF79 in Peking, China mit einer Darstellung der grundlegenden Funktionsprinzipien durch Koen Vos (MP3, ~70 MiB)
1344:
Wireline telephones which are manufactured in, imported to, or intended to be used in the US with Voice over IP service, on or after February 28, 2020, are required to meet the
1576:(IANA). Translation of E.164 number / private number to IP address allotted to any device and vice versa, by ISP to show compliance with IANA numbering scheme is not permitted.
675:
Network routers on high volume traffic links may introduce latency that exceeds permissible thresholds for VoIP. Excessive load on a link can cause congestion and associated
588:
with geographic relevance to the end-user(s) of the system. This infrastructure is external to the user of the system and is deployed and maintained by the service provider.
566:
VoIP solutions. Hosted systems are also generally better suited to smaller or personal use VoIP deployments, where a private system may not be viable for these scenarios.
2791:
1436:
1018:. Often VoIP implementations employ methods of translating non-E.164 identifiers to E.164 numbers and vice versa, such as the Skype-In service provided by Skype and the
1002:
to allow calls to be routed to and from VoIP subscribers and the PSTN/PLMN. VoIP implementations can also allow other identification techniques to be used. For example,
2641:
5372:
5015:
3304:
1138:
are optimized for the representation of the human voice and the proper timing of the modem signals cannot be guaranteed in a packet-based, connectionless network.
4827:
RADVision and Intel Target Compatibility Between RADVision's H.323/320 Videoconferencing Gateway And Intel's Business Video Conferencing And TeamStation Products.
3737:
4280:
4233:
802:(AAL5) to segment each Ethernet packet into a series of 53-byte ATM cells for transmission, reassembling them back into Ethernet frames at the receiving end.
532:
network, so that it is no longer necessary to carry both a desktop phone and a cell phone. Maintenance becomes simpler as there are fewer devices to oversee.
4437:
581:
VoIP solutions involve a service provider or telecommunications carrier hosting the telephone system as a software solution within their own infrastructure.
4524:
6152:
3202:
1531:
remained blocked from being used for voice and video calls, constricting residents to use paid services from the country's state-owned telecom providers.
4268:
269:– Creating reliable transmission over unreliable protocols, which may involve acknowledging receipt of data and retransmitting data that wasn't received.
3580:
3261:"RFC 3969– The Internet Assigned Number Authority (IANA) Uniform Resource Identifier (URI) Parameter Registry for the Session Initiation Protocol (SIP)"
1503:(UAE), it is illegal to provide or use unauthorized VoIP services. Web sites of unlicensed VoIP providers have been blocked. Some VoIP services such as
520:
is converting its field offices of 63,000 workers from traditional phone installations to a VoIP infrastructure carried over its existing data network.
3132:
1087:
of a corporate entity, in which case the IP address being used for customer communications may belong to the enterprise, not the residential ISP. Such
2873:
1515:
On March 24, 2020, the United Arab Emirates loosened restriction on VoIP services earlier prohibited in the country, to ease communication during the
1320:(NSA) released comprehensive documents describing the four attack planes of a communications system – the network, perimeter, session controllers and
1080:
allocated to the network router and the known service address. Some ISPs do not track the automatic assignment of IP addresses to customer equipment.
1864:
1618:
668:
and back; delays of 400–600 ms are typical. Latency can be minimized by marking voice packets as being delay-sensitive with QoS methods such as
3665:
4073:
3180:
216:. These solutions typically allow dynamic interconnection between users in any two domains of the Internet, when a user wishes to place a call.
5051:
Schnell, Markus; Schmidt, Markus; Jander, Manuel; Albert, Tobias; Geiger, Ralf; Ruoppila, Vesa; Ekstrand, Per; Bernhard, Grill (October 2008).
4126:
297:– Determining what type of media to send (audio, video, etc.), how to encode/decode it, and how to send/receive it (IP addresses, ports, etc.).
4826:
4178:
1203:
connection over traditional phone lines, such as digitizing and digital transmission, are already in place with VoIP. It is necessary only to
5365:
4203:
1111:
4239:. New Delhi India: Telecom Regulatory Authority of India (TRAI). p. 16 (Section 2.2.1.2 PC–to–Phone Internet telephony). Archived from
122:. Various codecs exist that optimize the media stream based on application requirements and network bandwidth; some implementations rely on
6860:
6832:
6827:
5852:
2422:
630:
However, VoIP traffic to and from the on-premises systems can often also be sent over secure private links. Examples include personal VPN,
4674:
4644:
4328:
3935:
3037:
279:(sometimes glossed as simply a "call"), which is a connection between two or more peers that provides a context for further communication.
5265:
4234:"Telecom Regulatory Authority of India (TRAI) Consultation paper on Issues related to Internet Telephony. Consultation Paper No. 11/2008"
2158:
2007: VoIP device manufacturers and sellers boom in Asia, specifically in the Philippines where many families of overseas workers reside.
3810:
1313:. Public Secure VoIP is also available with free GNU software and in many popular commercial VoIP programs via libraries, such as ZRTP.
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5171:
4390:
1920:
of the Defense Advanced Research Projects Agency (DARPA), agree to separate IP from TCP, and create UDP for carrying real-time traffic.
402:
5198:
4152:
3500:
1558:
PC / a device / Adapter conforming to the standard of any international agencies like- ITU or IETF etc. in India to PSTN/PLMN abroad.
3888:
2032:
begins development of standards for the transmission and signaling of voice communications over Internet Protocol networks with the
1336:
support that is compatible with the PSTN. Many VoIP service providers also allow callers to configure custom caller ID information.
707:
The receiver must resequence IP packets that arrive out of order and recover gracefully when packets arrive too late or not at all.
5358:
3453:
1404:
As the popularity of VoIP grows, governments are becoming more interested in regulating VoIP in a manner similar to PSTN services.
361:, control protocol for media gateways across a converged internetwork consisting of the traditional PSTN and modern packet networks
223:, VoIP is also available on many personal computers and other Internet access devices. Calls and SMS text messages may be sent via
3850:
3016:
106:
and involve signaling, channel setup, digitization of the analog voice signals, and encoding. Instead of being transmitted over a
3767:
3624:
2681:
1820:, fueled widespread interest and entrepreneurship in voice-over-IP services, applying new Internet technology paradigms, such as
3556:
3353:
1645:
VoIP service—those who are unable to determine the location of their users—are exempt from state telecommunications regulation.
860:(MAC) layer. The standard is considered of critical importance for delay-sensitive applications, such as voice over wireless IP.
291:), negotiating capabilities, and call control (such as hold, mute, transfer/forwarding, dialing DTMF keys during a call , etc.).
6854:
2847:
2795:
1255:
558:
While many use cases still remain for private or on-premises VoIP systems, the wider market has been gradually shifting toward
3416:
3391:
2562:
1122:
or other methods, the VoIP E911 information is accurate only if subscribers keep their emergency address information current.
6849:
6839:
6819:
6621:
5097:
3698:
3557:"Internet Protocol Telephony & Voice over Internet Protocol Security Technical Implementation Guide Version 2, Release 2"
3337:
2226:
1653:
5238:
2764:
1118:
system is based on a static table lookup. Unlike in cellular phones, where the location of an E911 call can be traced using
747:
medium (e.g. optical fiber) and the routers driving them do not have enough buffering for queuing delays to be significant.
489:
It is increasingly common for telecommunications providers to use VoIP telephony over dedicated and public IP networks as a
1751:
kbps, leading to the first successful real-time conversation over ARPANET in 1974, between Culler-Harrison Incorporated in
1617:
contributions, and other mandated payments; and enable law enforcement authorities to conduct surveillance pursuant to the
1218:
The security concerns for VoIP telephone systems are similar to those of other Internet-connected devices. This means that
370:
5986:
4840:
1083:
IP communication provides for device mobility. For example, a residential broadband connection may be used as a link to a
856:
standard that defines a set of quality-of-service enhancements for wireless LAN applications through modifications to the
6911:
6844:
6690:
5701:
5601:
1573:
1439:
regulates telephone service, including VoIP telephony service. VoIP services operating in Canada are required to provide
1298:
1282:
1262:
1196:
1171:
handsets to a base station, or that have other modern phone features, such as built-in voicemail or phone book features.
1100:
704:. But since every packet must contain protocol headers, this increases relative header overhead on every link traversed.
376:
4857:"H.323 Visual telephone systems and equipment for local area networks which provide a non-guaranteed quality of service"
4481:"A History of Realtime Digital Speech on Packet Networks: Part II of Linear Predictive Coding and the Internet Protocol"
2949:
6616:
4582:
M. R. Schroeder and B. S. Atal, "Code-excited linear prediction (CELP): high-quality speech at very low bit rates," in
3163:
2097:
146:
493:
to connect switching centers and to interconnect with other telephony network providers; this is often referred to as
6710:
5716:
5154:
4998:
4447:
3745:
2349:
1349:
1045:
970:
87:
4286:
4240:
3650:
1212:
627:. For remote and external endpoints, available connectivity options mirror those of Hosted or Cloud VoIP solutions.
6947:
6495:
6043:
5845:
5696:
3478:
2071:
1638:
6606:
5381:
4555:
719:, deliberately increasing latency to improve the chance that each packet will be on hand when it is time for the
4007:
3967:
6601:
5721:
1942:
1913:
1846:
1764:
1744:
952:
948:
517:
352:
283:
4099:
3936:"The Road to Broadband Development in Developing Countries is through Competition Driven by Wireless and VOIP"
3098:
2821:
231:
network. VoIP provides a framework for consolidation of all modern communications technologies using a single
6626:
3642:
3591:
2707:
2667:
2241:
1633:
operators also receive the benefit of certain US telecommunications regulations, including an entitlement to
684:
490:
743:. Most Internet backbone links are now so fast (e.g. 10 Gbit/s) that their delays are dominated by the
6901:
6662:
6559:
6102:
5897:
5869:
5417:
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917:(delay), post-dial delay, and echo. The metrics are determined by VoIP performance testing and monitoring.
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Telephones for traditional residential analog service are usually connected directly to telephone company
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A VoIP phone is necessary to connect to a VoIP service provider. This can be implemented in several ways:
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The steps and principles involved in originating VoIP telephone calls are similar to traditional digital
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Prabhakar, G.; Rastogi, R.; Thotton, M (2005). "OSS Architecture & Requirements for VoIP Networks".
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defines 8 different classes of service (including one dedicated to voice) for traffic on layer-2 wired
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114:. They transport media streams using special media delivery protocols that encode audio and video with
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lifted the ban on VoIPs, in an attempt to reduce operational costs and spur digital entrepreneurship.
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DSL modems typically provide Ethernet connections to local equipment, but inside they may actually be
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For on-premises systems, local endpoints within the same location typically connect directly over the
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Inter-Network Operations Center Dial-by-ASN (INOC-DBA), a Resource for the Network Operator Community
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Montazerolghaem, Ahmadreza; Moghaddam, Mohammad Hossein Yaghmaee; Leon-Garcia, Alberto (March 2018).
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4204:"UAE loosens some VoIP restrictions as residents in lockdown call for end to WhatsApp and Skype ban"
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Internet telephony is permitted to the ISP with restrictions. The following services are permitted:
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International Telecommunication Union, Standardization Sector (ITU-T), Study Group 15 (1993-1996),
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the location is automatically determined from its databases and displayed on the operator console.
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in analog circuitry and an acoustic path from the receive to transmit signal at the receiving end.
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medium to large enterprises, while another is targeting the small-to-medium business (SMB) market.
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Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004
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because of LCR options, VoIP needs to provide a certain level of reliability when handling calls.
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even for maximum-sized packets. An alternative to preemption on slower links, such as dialup and
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Beyond VoIP Protocols: Understanding Voice Technology and Networking Techniques for IP Telephony
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for quality-of-service mechanisms that help VoIP applications work well even in the presence of
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The technical details of many VoIP protocols create challenges in routing VoIP traffic through
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3786:"NSA Releases Guidance on Securing Unified Communications and Voice and Video over IP Systems"
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Secure voice over secure IP may be implemented by encrypting the media with protocols such as
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An end-user is allowed to make PC–to-Phone Internet Telephony calls only on PSTN/PLMN abroad.
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Such emergency services are provided by VoIP vendors in the United States by a system called
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755:
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303:– Transferring the actual media in the call, such as audio, video, text messages, files, etc.
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1984:
1993 Release of VocalChat, a commercial packet network PC voice communication software from
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At the VoIP level, a phone or gateway may identify itself by its account credentials with a
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Lutzky, Manfred; Schuller, Gerald; Gayer, Marc; Krämer, Ulrich; Wabnik, Stefan (May 2004).
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385:(SDP), a syntax for session initiation and announcement for multi-media communications and
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17:
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by the dominant operator, restrictions on the use of VoIP are often imposed, including in
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Dedicated VoIP phones connect directly to the IP network using technologies such as wired
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US telecommunication companies petition the US Congress to ban Internet phone technology.
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are often employed to enable VoIP calls to and from protected networks. Other methods to
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to play it. The added delay is thus a compromise between excessive latency and excessive
190:
158:
48:
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Booth, C (2010). "Chapter 2: IP Phones, Software VoIP, and Integrated and Mobile VoIP".
2131:
network is deployed; this is also the first voice network to reach all seven continents.
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and her team filed many patents related to the technology. By the late 1990s, the first
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Please help update this article to reflect recent events or newly available information.
516:(PBX) lines installed internationally were VoIP. For example, in the United States, the
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International Journal of Advanced Research in Computer Science and Software Engineering
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On the early ARPANET, real-time voice communication was not possible with uncompressed
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Throughout the developing world, particularly in countries where regulation is weak or
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462:. These are typically designed in the style of traditional digital business telephones.
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Valin, Jean-Marc; Maxwell, Gregory; Terriberry, Timothy B.; Vos, Koen (October 2013).
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may have SIP clients built into the firmware or available as an application download.
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garnered over 5000 signatures, in response to which the website was blocked in UAE.
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1966:
1991: Speak Freely, a voice-over-IP application, was released to the public domain.
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standard, which provides a way to create a high-speed (up to 1 gigabit per second)
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to reduce its transmission rate to alleviate the congestion. But VoIP usually uses
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specifically refer to the provisioning of voice and other communications services (
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1867:(IEEE) publishes a paper entitled "A Protocol for Packet Network Interconnection".
817:, carry Ethernet without intermediate ATM/AAL5 layers, and they generally support
417:, proprietary Internet telephony protocol suite based on peer-to-peer architecture
373:(RTCP), sister protocol for RTP providing stream statistics and status information
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Technical Note on Illegal International Long Distance telephone Exchange in India
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1974: The first successful real-time conversation over ARPANET achieved using 2.4
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priority tagging so that VoIP can be queued ahead of less time-critical traffic.
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Echo can also be an issue for PSTN integration. Common causes of echo include
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MPEG-4 Enhanced Low Delay AAC - A New Standard for High Quality Communication
4732:
4543:
4509:
3581:"Secure Voice over IP (SVoIP) vs. Voice over Secure IP (VoSIP) Installations"
2991:
2540:
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1969:
1992: The Frame Relay Forum conducts development of standards for voice over
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1793:
1729:
1701:
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712:
405:(XMPP), instant messaging, presence information, and contact list maintenance
138:
131:
127:
1613:; make service accessible to people with disabilities; pay regulatory fees,
1324:– and explaining security risks and mitigation techniques for each of them.
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1215:, may eliminate the need for personnel to greet and switch incoming calls.
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3217:"RFC 3824– Using E.164 numbers with the Session Initiation Protocol (SIP)"
27:
Methods of delivering voice communications and multimedia over IP networks
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3811:"Deploying Secure Unified Communications/Voice and Video over IP Systems"
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1977:
1970:
1960:, in addition to commercial packet voice products from companies such as
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331:
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119:
115:
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3150:"Performance and Stress Testing of SIP Servers, Clients and IP Networks"
762:(RTCP) extended reports, SIP RTCP summary reports, H.460.9 Annex B (for
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6112:
6068:
6038:
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4500:
3183:. ixc.ua. May 20, 2011. Archived from the original on November 11, 2012
2983:
2688:. Total Telecom Online. Archived from the original on February 17, 2006
2173:
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2055:
1981:
provide the basis for the Real Time Streaming Protocol (RTSP) standard.
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1167:
1077:
955: in this section. Unsourced material may be challenged and removed.
220:
123:
44:
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A standards-based solution for reliably delivering fax-over-IP is the
555:
PBX deployment model for connecting an office to local PSTN networks.
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6063:
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5757:
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5477:
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4179:"Etisalat launches new calling app plan days after Skype disruptions"
3354:"Keeping your telephone number when you change your service provider"
3305:"Application-level Network Interoperability and the Evolution of IMS"
3063:
2165:
codec introduced, using LPC algorithm, and used for voice calling in
2018:
2014:
1961:
1917:
1333:
1290:
1274:
1115:
1068:
476:
386:
103:
4586:
International Conference on Acoustics, Speech, and Signal Processing
4232:
Mahanagar Doorsanchar Bhawan and Jawahar Lal Nehru Marg (May 2008).
3038:"Optical Packet Buffers for Backbone Internet Routers | Request PDF"
2584:
2021:
initiated standardization activities for VoIP communications system.
1242:, used to interconnect to transit networks or the Internet. Private
930:
750:
A number of protocols have been defined to support the reporting of
309:– Providing out-of-band content or feedback about the media such as
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1985:
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3133:"Voice over IP (VoIP) Performance Evaluation on VMware vSphere® 5"
700:(DSL), is to reduce the maximum transmission time by reducing the
174:
149:(MDCT) compression methods. Popular codecs include the MDCT-based
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6758:
5976:
5445:
4721:"Network World - Startup targets desktop Videoconferencing arena"
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2152:
2105:
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Advanced Content Delivery, Streaming, and Cloud Services (Pg 34)
3851:"Hearing Aid Compatibility for Wireline and Wireless Telephones"
2155:
wideband codec introduced, using MDCT and CELP (LPC) algorithms.
1763:. LPC has since been the most widely used speech coding method.
1747:(NTT) in 1966. LPC was capable of speech compression down to 2.4
6803:
6763:
6085:
5515:
5450:
3912:
3666:"Packet loss concealment in a secure voice over IP environment"
3664:
White, C.M.; Teague, K.A.; Daniel, E.J. (November 7–10, 2004).
3454:"Keep your VoIP E911 service in compliance with this checklist"
2187:
2115:
2075:
1935:
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Secure calls are possible using standardized protocols such as
988:
are specially designed to link calls that are passed via VoIP.
910:
657:
631:
431:
150:
3768:"Secure VOIP calling, free software, and the right to privacy"
3617:
International Journal of Computer Science and Network Security
2969:
2743:"Learn to Make Free or Inexpensive Calls Using SIP on Android"
2337:
251:
in applications such as VoIP phones, mobile applications, and
6788:
6725:
6033:
5435:
4719:
IDG Network World Inc; Eckerson, Wayne (September 21, 1992).
4718:
4525:"Application of MFCC in Text Independent Speaker Recognition"
4127:"Etisalat launches new unlimited calling plan with VoIP apps"
3663:
2166:
2148:
VoIP service is launched by TelEvolution, Inc. of California.
2135:
2042:
2033:
2029:
2010:
1992:
1957:
1809:
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999:
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224:
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186:
182:
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5579:
3840:, Blog: "Hello Mom, I'm a Fake!" (Telespoof and Fakecaller).
3501:"4.4 VOIP – Regulatory Issues – Universal Service"
2114:
The MDCT is adapted into the LD-MDCT algorithm, used in the
1051:
A voice call originating in the VoIP environment also faces
367:(RTP), transport protocol for real-time audio and video data
6730:
5568:
5558:
4983:
Hersent, Olivier; Petit, Jean-Pierre; Gurle, David (2005).
4702:"The History of VoIP Over the Last 55 Years (1966 to 2021)"
4367:
3986:
Canadian Radio-television and Telecommunications Commission
3875:
2193:
2162:
1924:
1883:
1628:
VoIP (fully connected to the PSTN) are mandated to provide
1476:
1437:
Canadian Radio-television and Telecommunications Commission
1302:
1266:
1251:
1142:
877:
810:
343:(SIP), connection management protocol developed by the IETF
194:
166:
5050:
2762:
5773:
5292:
5230:
5013:
4282:
Stars and Stripes: USFK deal keeps VoIP access for troops
1956:
1986: Proposals from various standards organizations for
1415:
where VoIP is taxed, Guyana where VoIP is prohibited. In
1131:
773:
The RTCP extended report VoIP metrics block specified by
624:
79:
75:
5272:
by Timothy B. Terriberry (65 minutes of video, see also
3116:"Methodology for SIP Infrastructure Performance Testing"
3086:
PacketCable Residential SIP Telephony Feature Definition
2648:. EE Times. Archived from the original on August 9, 2011
1211:
the existing data stream. Automated software, such as a
4391:"The State Of Cybersecurity Wiretapping's Fuzzy Future"
1519:. However, popular instant messaging applications like
197:, a codec that uses only 8 kbit/s each way called
5295:
High-Quality, Low-Delay Music Coding in the Opus Codec
5115:"State of the Art: Get Your Free Net Phone Calls Here"
2350:
1543:, it is legal to use VoIP, but it is illegal to have
994:
is a global numbering standard for both the PSTN and
535:
VoIP solutions aimed at businesses have evolved into
4227:
4225:
2340:
2334:
2190:
technology which supports VoIP directly in browsers.
2141:
2004: Commercial VoIP service providers proliferate.
2045:
speech codec introduced, using CELP (LPC) algorithm.
1596:
providing personal Internet services by contract to
484:
5380:
3889:"network infrastructure: getting started with VoIP"
3099:"VoIP performance measurement using QoS parameters"
2511:
IEEE Transactions on Network and Service Management
2382:
can be used for DSL connectivity without using ATM.
1568:, no other form of Internet Telephony is permitted.
1174:VoIP phones and VoIP telephone adapters connect to
5236:
4906:
4612:"A Protocol for Packet Network Intercommunication"
1893:kpbs LPC, between Culler-Harrison Incorporated in
1767:(CELP), a type of LPC algorithm, was developed by
4982:
4805:"The 10 that Established VOIP (Part 1: VocalTec)"
4647:. The National Science Foundation. Archived from
4222:
3790:National Security Agency/Central Security Service
2818:"Social Security to Build "World's Largest VOIP""
2507:"OpenSIP: Toward Software-Defined SIP Networking"
1991:1994: MTALK, a freeware LAN VoIP application for
1865:Institute of Electrical and Electronics Engineers
1619:Communications Assistance for Law Enforcement Act
1261:Standards for securing VoIP are available in the
6924:
5172:"Prospects bright for voice calls over internet"
4914:"The 10 that Established VOIP (Part 2: Level 3)"
4675:"VoIP Basics: Everything Beginners Should Know!"
3201:: CS1 maint: bot: original URL status unknown (
3088:, Technical Report, PKT-TR-RST-V03-071106 (2007)
2205:codec introduced, using MDCT and LPC algorithms.
1010:(usernames) whereas SIP implementations can use
355:(MGCP), connection management for media gateways
3121:. Miroslav Voznak, Jan Rozhon. August 14, 2016.
3054:RTP Control Protocol Extended Reports (RTCP XR)
2841:
2839:
1878:in August 1974, carrying barely intelligible 16
5087:
3608:Dunte, Markus; Ruland, Christoph (June 2007).
3011:
3009:
2921:"VoIP - Vulnerability over Internet Protocol?"
2423:"Voice Over IP : Protocols and Standards"
2414:
1945:(CELP), a type of LPC algorithm, developed by
1363:
1332:Voice over IP protocols and equipment provide
1182:which typically depend on the availability of
5846:
5595:
5366:
5256:
5092:. Los Alamitos: IEEE Computer Society Press.
3738:"Cellcrypt secure VOIP heading to BlackBerry"
1808:became available, and new protocols, such as
1112:Wireless Communications and Public Safety Act
435:Example of residential network including VoIP
4936:"RFC 2543, SIP: Session Initiation Protocol"
4609:
4578:
4576:
4338:
4153:"No Skype? Pay Dh50 monthly for video calls"
4074:"Saudi Arabia to lift ban on internet calls"
4048:"Saudi Arabia to lift ban on internet calls"
3640:
3417:"FCC Consumer Advisory VoIP and 911 Service"
2845:
2836:
2642:"WIRELESS: Carriers look to IP for backhaul"
2448:and the common encryption mechanism used is
2321:Variously pronounced as individual letters,
2180:, which uses the LD-MDCT-based AAC-LD codec.
1348:compatibility requirements set forth by the
1339:
1250:devices involve assistive protocols such as
43:, is a method and group of technologies for
6861:Global telecommunications regulation bodies
4938:. Handley, Schulzrinne, Schooler, Rosenberg
3607:
3325:
3006:
1293:, facilitate capturing VoIP conversations.
6897:
5853:
5839:
5602:
5588:
5373:
5359:
5132:
4589:(ICASSP), vol. 10, pp. 937–940, 1985.
3532:"Examining Two Well-Known Attacks on VoIP"
3451:
3181:"Importance of Softswitch VoIP Technology"
2794:. Government Computer News. Archived from
998:(PLMN). Most VoIP implementations support
411:, for peer-to-peer session control in XMPP
403:Extensible Messaging and Presence Protocol
5306:
5239:"Inside iPhone 4: FaceTime video calling"
5138:
4785:. Computer Telephony Interaction Magazine
4573:
4499:
4388:
4382:
4176:
4124:
3680:
3384:"TelePassport takes the sting out of MNP"
3062:
2522:
2068:(SIP) specification RFC 2543 is released.
1462:
971:Learn how and when to remove this message
683:. This signals a transport protocol like
86:) over the Internet, rather than via the
5044:
4976:
4125:Debusmann, Bernd Jr. (January 9, 2018).
3263:. The Internet Society. December 1, 2004
2944:
2942:
2940:
2938:
2936:
2934:
2871:
2479:
599:
430:
243:Voice over IP has been implemented with
5189:
5007:
4712:
4474:
4472:
4470:
4468:
4466:
4302:"Cybertelecom :: VoIP :: FCC"
4023:"Oman cuffs 212 for selling VoIP calls"
3641:Stringfellow, Brian (August 15, 2001).
3529:
3452:Noworatzky, Daniel (February 6, 2019).
3164:"Testing Voice over IP (VolP) Networks"
2846:Korzeniowski, Peter (January 8, 2009).
2789:
2196:codec introduced, using MDCT algorithm.
1494:
1199:. Most of the facilities of creating a
613:
595:
439:Mass-market VoIP services use existing
14:
6925:
5860:
5286:
4699:
4693:
4668:
4666:
4150:
4100:"Don't worry, Skype is working in UAE"
3562:. DISA. April 21, 2006. Archived from
3411:
3409:
3017:"Quality of Service for Voice over IP"
2950:"Quality of Service for Voice over IP"
2365:IP networks may also be more prone to
1256:Interactive Connectivity Establishment
1092:roaming via another cellular company.
900:
727:, i.e. momentary audio interruptions.
569:
549:
5834:
5583:
5354:
5170:Remo, Michelle V. (August 27, 2007).
5112:
4522:
4368:"Voice Over Internet Protocol (VoIP)"
4177:Zacharias, Anna \ (January 8, 2018).
3988:. Government of Canada. April 4, 2005
2931:
2848:"Three Technologies You Need In 2009"
2599:"Voice Over Internet Protocol (VoIP)"
2485:
2420:
2227:Comparison of audio network protocols
1735:algorithm that was first proposed by
1654:Foreign Intelligence Surveillance Act
1641:via wholesale carriers. Providers of
1285:VoIP at the transport level by using
1161:
1032:
983:A VoIP media gateway controller (aka
637:
6907:
5218:. Wirevolution.com. January 13, 2009
5169:
5142:VoIP Voice and Fax Signal Processing
4478:
4463:
4299:
3630:from the original on April 19, 2023.
3219:. The Internet Society. June 1, 2004
3104:. A.H.Muhamad Amin. August 14, 2016.
2872:Callahan, Renee (December 9, 2008).
1652:is debating concerns changes to the
1367:
1099:(SIP) registrar. In such cases, the
953:adding citations to reliable sources
924:
758:(QoE) for VoIP calls. These include
371:Real-time Transport Control Protocol
5237:Daniel Eran Dilger (June 8, 2010).
4777:
4672:
4663:
4619:IEEE Transactions on Communications
3933:
3878:, What are some advantages of VoIP?
3406:
3050:
2421:Arora, Rakesh (November 23, 1999).
2007:commercial Internet phone software.
1724:. The solution to this problem was
1574:Internet Assigned Numbers Authority
1355:
1263:Secure Real-time Transport Protocol
1197:Secure Real-time Transport Protocol
1101:Internet telephony service provider
920:
584:Typically this will be one or more
377:Secure Real-time Transport Protocol
141:standards in VoIP are based on the
24:
5216:"Skype's new super wideband codec"
4700:McCraw, Corey (October 12, 2022).
4151:Maceda, Cleofe (January 8, 2018).
3913:"Global VOIP Policy Status Matrix"
3653:from the original on June 1, 2023.
3394:from the original on July 19, 2022
3044:
2874:"Businesses Move To Voice-Over-IP"
2098:modified discrete cosine transform
1775:in 1985. LPC algorithms remain an
1062:
884:(LAN) using existing home wiring (
833:Several protocols are used in the
426:
147:modified discrete cosine transform
25:
6964:
5319:
5139:Nagireddi, Sivannarayana (2008).
3855:Federal Communications Commission
3675:. Vol. 1. pp. 415–419.
2824:from the original on June 2, 2009
2790:Jackson, William (May 27, 2009).
2603:Federal Communications Commission
1685:in 1973 which was developed into
1639:incumbent local exchange carriers
1555:PC to PC; within or outside India
1446:
1350:Federal Communications Commission
1309:on a classified network, such as
1046:Federal Communications Commission
485:PSTN and mobile network providers
88:public switched telephone network
6906:
6896:
6887:
6886:
6875:
6496:Free-space optical communication
5815:
5805:
5339:
5325:
5208:
5163:
5106:
5081:
5017:A guideline to audio codec delay
4950:
4928:
4893:
4389:Greenberg, Andy (May 15, 2008).
4020:
3530:Thermos, Peter (April 5, 2006).
2763:Michael Dosch and Steve Church.
2582:
2330:
1689:which operated across the early
1603:
1564:Except whatever is described in
1372:
929:
852:is an approved amendment to the
506:
379:(SRTP), encrypted version of RTP
5382:Computer-mediated communication
5113:Pogue, David (August 2, 2007).
4871:
4849:
4819:
4797:
4771:
4746:
4637:
4610:Cerf, V.; Kahn, R. (May 1974).
4603:
4592:
4516:
4430:
4408:
4360:
4319:
4293:
4273:
4261:
4196:
4170:
4144:
4118:
4092:
4066:
4040:
4014:
4000:
3982:"Telecom Decision CRTC 2005-21"
3974:
3960:
3927:
3905:
3881:
3869:
3843:
3831:
3803:
3778:
3760:
3730:
3657:
3634:
3601:
3573:
3549:
3523:
3493:
3471:
3445:
3376:
3346:
3319:
3297:
3275:
3253:
3231:
3209:
3173:
3156:
3152:. StarTrinity. August 13, 2016.
3142:
3125:
3108:
3091:
3078:
3030:
2963:
2913:
2891:
2865:
2810:
2783:
2756:
2735:
2714:
2674:
2634:
2617:
2372:
2359:
2054:began development of its first
1712:kbps, much greater than the 2.4
1482:
1022:(ENUM) service in IMS and SIP.
940:needs additional citations for
5263:Presentation of the CELT codec
4960:. Asterisk.org. Archived from
4727:. IDG Network World Inc: 39–.
4442:. Willey. September 19, 2014.
3968:"VOICE OVER INTERNET PROTOCOL"
2765:"VoIP in the Broadcast Studio"
2591:
2576:
2555:
2498:
2457:
2396:
2315:
1943:Code-excited linear prediction
1914:Information Sciences Institute
1847:Nippon Telegraph and Telephone
1765:Code-excited linear prediction
1745:Nippon Telegraph and Telephone
1677:of the mid-twentieth century.
1583:
1125:
789:
518:Social Security Administration
353:Media Gateway Control Protocol
13:
1:
5609:
5330:The dictionary definition of
5088:Stapleton-Gray, Ross (2009).
3283:"Your personal online number"
2408:Cambridge Dictionaries Online
2389:
2242:High Bit Rate Media Transport
2058:, a term they coined in 1998.
1827:
1681:first demonstrated a form of
1648:Another legal issue that the
1637:and exchange of traffic with
1006:allows subscribers to choose
896:with the network controllers.
735:, jitter can be modeled as a
607:-based PBX for small business
395:(IAX), protocol used between
6882:Telecommunication portal
6663:Telecommunications equipment
5812:Telecommunication portal
5418:Virtual learning environment
5347:travel guide from Wikivoyage
4488:Found. Trends Signal Process
3332:. Cisco Press. p. 557.
2767:. Axia Audio. Archived from
1934:commissions the creation of
1327:
1305:. Secure voice over IP uses
473:have this function built in.
383:Session Description Protocol
365:Real-time Transport Protocol
238:
33:Voice over Internet Protocol
7:
6399:Alexander Stepanovich Popov
5531:Voice chat in online gaming
4673:Dua, Amit (July 29, 2021).
3588:General Dynamics C4 Systems
2972:Bell Labs Technical Journal
2563:"H.323 and SIP Integration"
2232:Comparison of VoIP software
2209:
2127:, the first inter-provider
2066:Session Initiation Protocol
1932:National Science Foundation
1814:Session Initiation Protocol
1779:in modern VoIP technology.
1364:Regulatory and legal issues
1240:network address translators
1190:
1097:Session Initiation Protocol
1067:A telephone connected to a
1020:E.164 number to URI mapping
1012:Uniform Resource Identifier
421:
341:Session Initiation Protocol
97:
92:plain old telephone service
55:(IP) networks, such as the
10:
6969:
6103:Telecommunications history
5201:February 10, 2013, at the
4780:"Internet Phone Release 4"
4523:Gupta, Shipra (May 2016).
3915:. Global IP Alliance. 2005
3691:10.1109/ACSSC.2004.1399165
3329:Packetcable Implementation
3307:. TMCnet.com. May 24, 2006
3138:. VMware. August 14, 2016.
2488:Library Technology Reports
2446:Layer 2 Tunneling Protocol
2100:(MDCT) is adopted for the
1664:The early developments of
1659:
1598:United States Forces Korea
1594:Internet service providers
1244:session border controllers
996:public land mobile network
828:
807:virtual circuit identifier
796:Asynchronous Transfer Mode
275:– Creating and managing a
6870:
6812:
6749:
6711:Public Switched Telephone
6671:
6635:
6592:
6533:
6523:telecommunication circuit
6484:Fiber-optic communication
6467:
6229:Francis Blake (telephone)
6176:
6024:Optical telecommunication
5868:
5802:
5766:
5735:
5687:Communications satellites
5674:
5653:
5617:
5551:
5486:
5428:Asynchronous conferencing
5426:
5388:
5299:Audio Engineering Society
5176:Philippine Daily Inquirer
5068:Audio Engineering Society
5031:Audio Engineering Society
4832:October 30, 2013, at the
4631:10.1109/TCOM.1974.1092259
3479:"Faxing over IP networks"
2925:www.continuitycentral.com
2820:. Government Technology.
2706:: CS1 maint: unfit URL (
2666:: CS1 maint: unfit URL (
2533:10.1109/TNSM.2017.2741258
2096:(DCT) variant called the
2094:discrete cosine transform
1426:
1381:This section needs to be
1340:Hearing aid compatibility
1271:analog telephony adapters
1042:mobile number portability
845:. Some examples include:
770:.30 and MGCP extensions.
702:maximum transmission unit
441:broadband Internet access
212:, adopted the concept of
6622:Orbital angular-momentum
6059:Satellite communications
5898:Communications satellite
5488:Synchronous conferencing
5297:. 135th AES Convention.
5279:August 10, 2011, at the
5060:. 125th AES Convention.
5023:. 116th AES Convention.
4838:VoiP Developer Solutions
4584:Proceedings of the IEEE
4479:Gray, Robert M. (2010).
4335:, 47 C.F.R. pt. 9 (2007)
3169:. IXIA. August 14, 2016.
2467:. Google Talkabout. 2006
2308:
1927:is described in RFC 791.
1903:Lexington, Massachusetts
1835:Linear predictive coding
1761:Lexington, Massachusetts
1726:linear predictive coding
1611:local number portability
1534:
1318:National Security Agency
1287:opportunistic encryption
1148:analog telephone adapter
1038:Local number portability
737:Gaussian random variable
711:results from changes in
467:analog telephone adapter
323:VoIP protocols include:
253:web-based communications
143:linear predictive coding
108:circuit-switched network
6948:Audio network protocols
6501:Molecular communication
6324:Gardiner Greene Hubbard
6153:Undersea telegraph line
5888:Cable protection system
5682:Cable protection system
5441:Electronic mailing list
5268:August 7, 2011, at the
4916:. iLocus. July 13, 2007
4418:. INTERNET HALL of FAME
3505:ICT Regulation Tool Kit
2682:"Mobile's IP challenge"
2257:IP Multimedia Subsystem
2237:Differentiated services
2087:private branch exchange
1792:, based on a patent by
1470:
1281:is available to secure
1089:off-premises extensions
1085:virtual private network
798:(ATM) modems. They use
698:digital subscriber line
666:geostationary satellite
514:Private branch exchange
393:Inter-Asterisk eXchange
247:and protocols based on
130:, while others support
112:packet-switched network
72:broadband phone service
6643:Communication protocol
6429:Charles Sumner Tainter
6244:Walter Houser Brattain
6189:Edwin Howard Armstrong
5997:Information revolution
5413:Social network service
5408:Collaborative software
5403:Communication software
4843:June 16, 2011, at the
4708:. Fits Small Business.
4681:. Business 2 Community
4679:business2community.com
4645:"The Launch of NSFNET"
4346:"VoIP and 911 Service"
3934:Proenza, Francisco J.
3901:on September 17, 2011.
3772:Free Software Magazine
3643:"Secure Voice Over IP"
3610:"Secure Voice-over-IP"
3597:on September 24, 2015.
2792:"SSA goes big on VOIP"
2585:"Voice OVER IP (VOIP)"
2369:that cause congestion.
2262:List of VoIP companies
1908:1977: Danny Cohen and
1899:MIT Lincoln Laboratory
1872:Network Voice Protocol
1757:MIT Lincoln Laboratory
1687:Network Voice Protocol
1273:, as well as for some
800:ATM Adaptation Layer 5
709:Packet delay variation
608:
537:unified communications
445:direct inbound dialing
436:
233:unified communications
157:), the LPC/MDCT-based
90:(PSTN), also known as
6617:Polarization-division
6349:Narinder Singh Kapany
6314:Erna Schneider Hoover
6234:Jagadish Chandra Bose
6214:Alexander Graham Bell
5945:online video platform
5822:Telephones portal
5473:Bulletin board system
5147:John Wiley & Sons
4991:John Wiley & Sons
4331:June 8, 2010, at the
4267:Harish Kumar Gangwar
3489:on December 18, 2023.
3390:. November 13, 2006.
3239:"Create a Skype Name"
2378:Technologies such as
1777:audio coding standard
1704:packets, which had a
1698:pulse-code modulation
1110:(E911), based on the
756:quality of experience
733:central limit theorem
603:
434:
334:, voice over IP, and
245:proprietary protocols
193:voice codec known as
137:The most widely used
6459:Vladimir K. Zworykin
6419:Almon Brown Strowger
6389:Charles Grafton Page
6044:Prepaid mobile phone
5972:Electrical telegraph
5784:Telephone newspapers
4901:Recommendation G.729
4706:fitsmallbusiness.com
4538:(5): 805–810 (806).
4306:www.cybertelecom.org
4080:. September 20, 2017
4054:. September 20, 2017
3364:on December 12, 2009
3326:Jeff Riddel (2007).
2899:"Skype For Business"
2722:"Android SIP Client"
2450:Secure Sockets Layer
2222:Call-through telecom
1947:Manfred R. Schroeder
1769:Manfred R. Schroeder
1566:condition (ii) above
1501:United Arab Emirates
1495:United Arab Emirates
1224:VoIP vulnerabilities
1027:impedance mismatches
949:improve this article
858:media access control
760:RTP Control Protocol
596:Private VoIP systems
330:, open standard for
47:for the delivery of
6409:Johann Philipp Reis
6168:Wireless revolution
6130:The Telephone Cases
5987:Hydraulic telegraph
5707:Mobile phone signal
5506:Internet Relay Chat
5274:presentation slides
4964:on January 23, 2009
4561:on October 18, 2019
4370:. November 18, 2010
4348:. FCC. May 26, 2011
4289:on January 13, 2010
3569:on August 25, 2009.
2605:. November 18, 2010
2433:on January 19, 2024
2272:RTP payload formats
2247:Integrated services
2104:codec, used in the
1845:and Shuzo Saito of
1743:and Shuzo Saito of
1487:In September 2017,
1463:Arab states of the
1443:emergency service.
901:Performance metrics
784:mean opinion scores
656:, packet loss, and
570:Hosted VoIP systems
550:Delivery mechanisms
68:broadband telephony
49:voice communication
6607:Frequency-division
6584:Telephone exchange
6454:Charles Wheatstone
6384:Jun-ichi Nishizawa
6359:Innocenzo Manzetti
6294:Reginald Fessenden
6029:Optical telegraphy
5862:Telecommunications
5697:Free-space optical
5345:Internet telephony
5119:The New York Times
4958:"What is Asterisk"
4501:10.1561/2000000036
4246:on October 6, 2014
3857:. October 30, 2014
3433:on August 10, 2010
2984:10.1002/bltj.20077
2771:on October 7, 2011
1895:Goleta, California
1874:(NVP) tested over
1837:(LPC) proposed by
1753:Goleta, California
1675:telecommunications
1316:In June 2021, the
1222:with knowledge of
1162:Power requirements
1053:least-cost routing
1033:Number portability
1014:(URIs) similar to
888:, phone lines and
882:Local area network
843:network congestion
752:quality of service
645:quality of service
638:Quality of service
609:
526:personal computers
437:
313:, statistics, etc.
307:Quality of service
273:Session management
64:Internet telephony
62:The broader terms
6920:
6919:
6658:Store and forward
6653:Data transmission
6567:Network switching
6518:Transmission line
6364:Guglielmo Marconi
6329:Internet pioneers
6194:Mohamed M. Atalla
6163:Whistled language
5828:
5827:
5661:Answering machine
5577:
5576:
5521:Videoconferencing
5501:Instant messaging
5496:Data conferencing
5398:Online discussion
5099:978-0-7695-3568-5
4825:The free Library
4599:Audio Transceiver
4300:Pershing, Genny.
3818:media.defense.gov
3748:on April 24, 2009
3700:978-0-7803-8622-8
3339:978-1-58705-181-4
2686:www.totaltele.com
2465:"XMPP Federation"
1843:Nagoya University
1741:Nagoya University
1615:universal service
1517:COVID-19 pandemic
1421:telecommunication
1402:
1401:
1307:Type 1 encryption
1228:denial-of-service
1184:mains electricity
981:
980:
973:
805:Using a separate
612:QoS control (see
295:Media description
227:or the carrier's
165:), the LPC-based
128:compressed speech
53:Internet Protocol
16:(Redirected from
6960:
6953:Office equipment
6910:
6909:
6900:
6899:
6890:
6889:
6880:
6879:
6878:
6751:Notable networks
6741:Wireless network
6681:Cellular network
6673:Types of network
6648:Computer network
6535:Network topology
6449:Thomas A. Watson
6304:Oliver Heaviside
6289:Philo Farnsworth
6264:Daniel Davis Jr.
6239:Charles Bourseul
6199:John Logie Baird
5908:Data compression
5903:Computer network
5855:
5848:
5841:
5832:
5831:
5820:
5819:
5818:
5810:
5809:
5808:
5774:Fax transmission
5722:Submarine cables
5604:
5597:
5590:
5581:
5580:
5543:Web conferencing
5478:Online guestbook
5375:
5368:
5361:
5352:
5351:
5343:
5329:
5313:
5312:
5310:
5290:
5284:
5260:
5254:
5253:
5251:
5249:
5234:
5228:
5227:
5225:
5223:
5212:
5206:
5196:Audio-Mitschnitt
5193:
5187:
5186:
5184:
5182:
5167:
5161:
5160:
5136:
5130:
5129:
5127:
5125:
5110:
5104:
5103:
5085:
5079:
5078:
5076:
5074:
5059:
5048:
5042:
5041:
5039:
5037:
5022:
5011:
5005:
5004:
4980:
4974:
4973:
4971:
4969:
4954:
4948:
4947:
4945:
4943:
4932:
4926:
4925:
4923:
4921:
4910:
4904:
4897:
4891:
4890:
4888:
4886:
4875:
4869:
4868:
4866:
4864:
4853:
4847:
4823:
4817:
4816:
4814:
4812:
4801:
4795:
4794:
4792:
4790:
4784:
4775:
4769:
4768:
4766:
4764:
4758:
4750:
4744:
4743:
4741:
4739:
4716:
4710:
4709:
4697:
4691:
4690:
4688:
4686:
4670:
4661:
4660:
4658:
4656:
4641:
4635:
4634:
4616:
4607:
4601:
4596:
4590:
4580:
4571:
4570:
4568:
4566:
4560:
4554:. Archived from
4529:
4520:
4514:
4513:
4503:
4485:
4476:
4461:
4460:
4458:
4456:
4434:
4428:
4427:
4425:
4423:
4412:
4406:
4405:
4403:
4401:
4386:
4380:
4379:
4377:
4375:
4364:
4358:
4357:
4355:
4353:
4342:
4336:
4323:
4317:
4316:
4314:
4312:
4297:
4291:
4290:
4285:, archived from
4277:
4271:
4265:
4259:
4258:
4253:
4251:
4245:
4238:
4229:
4220:
4219:
4217:
4215:
4210:. March 26, 2020
4200:
4194:
4193:
4191:
4189:
4174:
4168:
4167:
4165:
4163:
4148:
4142:
4141:
4139:
4137:
4131:Arabian Business
4122:
4116:
4115:
4113:
4111:
4096:
4090:
4089:
4087:
4085:
4070:
4064:
4063:
4061:
4059:
4044:
4038:
4037:
4035:
4033:
4018:
4012:
4011:
4004:
3998:
3997:
3995:
3993:
3978:
3972:
3971:
3964:
3958:
3957:
3955:
3953:
3947:
3941:. Archived from
3940:
3931:
3925:
3924:
3922:
3920:
3909:
3903:
3902:
3900:
3894:. Archived from
3893:
3885:
3879:
3873:
3867:
3866:
3864:
3862:
3847:
3841:
3835:
3829:
3828:
3826:
3824:
3815:
3807:
3801:
3800:
3798:
3796:
3782:
3776:
3775:
3764:
3758:
3757:
3755:
3753:
3744:. Archived from
3742:Networkworld.com
3734:
3728:
3727:
3725:
3723:
3717:
3711:. Archived from
3684:
3670:
3661:
3655:
3654:
3638:
3632:
3631:
3629:
3614:
3605:
3599:
3598:
3596:
3590:. Archived from
3585:
3577:
3571:
3570:
3568:
3561:
3553:
3547:
3546:
3544:
3542:
3527:
3521:
3520:
3518:
3516:
3507:. Archived from
3497:
3491:
3490:
3485:. Archived from
3475:
3469:
3468:
3466:
3464:
3449:
3443:
3442:
3440:
3438:
3432:
3426:. Archived from
3421:
3413:
3404:
3403:
3401:
3399:
3380:
3374:
3373:
3371:
3369:
3360:. Archived from
3350:
3344:
3343:
3323:
3317:
3316:
3314:
3312:
3301:
3295:
3294:
3292:
3290:
3279:
3273:
3272:
3270:
3268:
3257:
3251:
3250:
3248:
3246:
3235:
3229:
3228:
3226:
3224:
3213:
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3200:
3192:
3190:
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3170:
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3140:
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3112:
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3095:
3089:
3082:
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3075:
3066:
3064:10.17487/RFC3611
3051:Caceres, Ramon.
3048:
3042:
3041:
3034:
3028:
3027:
3025:
3023:
3013:
3004:
3003:
2967:
2961:
2960:
2958:
2956:
2946:
2929:
2928:
2917:
2911:
2910:
2908:
2906:
2895:
2889:
2888:
2886:
2884:
2869:
2863:
2862:
2860:
2858:
2843:
2834:
2833:
2831:
2829:
2814:
2808:
2807:
2805:
2803:
2798:on July 28, 2011
2787:
2781:
2780:
2778:
2776:
2760:
2754:
2753:
2751:
2749:
2739:
2733:
2732:
2730:
2728:
2718:
2712:
2711:
2705:
2697:
2695:
2693:
2678:
2672:
2671:
2665:
2657:
2655:
2653:
2638:
2632:
2631:
2629:
2621:
2615:
2614:
2612:
2610:
2595:
2589:
2588:
2580:
2574:
2573:
2571:
2569:
2559:
2553:
2552:
2526:
2502:
2496:
2495:
2483:
2477:
2476:
2474:
2472:
2461:
2455:
2454:
2440:
2438:
2429:. Archived from
2418:
2412:
2411:
2400:
2383:
2376:
2370:
2363:
2357:
2353:
2347:
2346:
2343:
2342:
2339:
2336:
2327:
2319:
2111:coding standard.
1892:
1881:
1839:Fumitada Itakura
1750:
1737:Fumitada Itakura
1733:data compression
1715:
1711:
1567:
1397:
1394:
1388:
1376:
1375:
1368:
1356:Operational cost
1201:secure telephone
976:
969:
965:
962:
956:
933:
925:
921:PSTN integration
741:bottleneck links
649:circuit switched
632:site-to-site VPN
21:
6968:
6967:
6963:
6962:
6961:
6959:
6958:
6957:
6923:
6922:
6921:
6916:
6876:
6874:
6866:
6808:
6745:
6667:
6631:
6588:
6537:
6529:
6470:
6463:
6369:Robert Metcalfe
6224:Tim Berners-Lee
6172:
5992:Information Age
5864:
5859:
5829:
5824:
5816:
5814:
5806:
5804:
5798:
5779:Telephone calls
5762:
5731:
5670:
5649:
5640:Satellite phone
5630:Cable telephony
5613:
5608:
5578:
5573:
5547:
5482:
5422:
5384:
5379:
5322:
5317:
5316:
5291:
5287:
5281:Wayback Machine
5270:Wayback Machine
5261:
5257:
5247:
5245:
5235:
5231:
5221:
5219:
5214:
5213:
5209:
5203:Wayback Machine
5194:
5190:
5180:
5178:
5168:
5164:
5157:
5137:
5133:
5123:
5121:
5111:
5107:
5100:
5086:
5082:
5072:
5070:
5057:
5049:
5045:
5035:
5033:
5020:
5012:
5008:
5001:
4981:
4977:
4967:
4965:
4956:
4955:
4951:
4941:
4939:
4934:
4933:
4929:
4919:
4917:
4912:
4911:
4907:
4898:
4894:
4884:
4882:
4877:
4876:
4872:
4862:
4860:
4855:
4854:
4850:
4845:Wayback Machine
4834:Wayback Machine
4824:
4820:
4810:
4808:
4803:
4802:
4798:
4788:
4786:
4782:
4776:
4772:
4762:
4760:
4756:
4752:
4751:
4747:
4737:
4735:
4717:
4713:
4698:
4694:
4684:
4682:
4671:
4664:
4654:
4652:
4643:
4642:
4638:
4614:
4608:
4604:
4597:
4593:
4581:
4574:
4564:
4562:
4558:
4527:
4521:
4517:
4483:
4477:
4464:
4454:
4452:
4450:
4436:
4435:
4431:
4421:
4419:
4414:
4413:
4409:
4399:
4397:
4387:
4383:
4373:
4371:
4366:
4365:
4361:
4351:
4349:
4344:
4343:
4339:
4333:Wayback Machine
4324:
4320:
4310:
4308:
4298:
4294:
4279:
4278:
4274:
4266:
4262:
4249:
4247:
4243:
4236:
4230:
4223:
4213:
4211:
4202:
4201:
4197:
4187:
4185:
4175:
4171:
4161:
4159:
4149:
4145:
4135:
4133:
4123:
4119:
4109:
4107:
4106:. June 26, 2017
4098:
4097:
4093:
4083:
4081:
4072:
4071:
4067:
4057:
4055:
4046:
4045:
4041:
4031:
4029:
4019:
4015:
4008:"Voice over IP"
4006:
4005:
4001:
3991:
3989:
3980:
3979:
3975:
3966:
3965:
3961:
3951:
3949:
3948:on June 2, 2012
3945:
3938:
3932:
3928:
3918:
3916:
3911:
3910:
3906:
3898:
3891:
3887:
3886:
3882:
3874:
3870:
3860:
3858:
3849:
3848:
3844:
3836:
3832:
3822:
3820:
3813:
3809:
3808:
3804:
3794:
3792:
3784:
3783:
3779:
3766:
3765:
3761:
3751:
3749:
3736:
3735:
3731:
3721:
3719:
3718:on May 17, 2006
3715:
3701:
3668:
3662:
3658:
3639:
3635:
3627:
3612:
3606:
3602:
3594:
3583:
3579:
3578:
3574:
3566:
3559:
3555:
3554:
3550:
3540:
3538:
3528:
3524:
3514:
3512:
3511:on June 4, 2009
3499:
3498:
3494:
3483:Soft-Switch.org
3477:
3476:
3472:
3462:
3460:
3450:
3446:
3436:
3434:
3430:
3419:
3415:
3414:
3407:
3397:
3395:
3382:
3381:
3377:
3367:
3365:
3352:
3351:
3347:
3340:
3324:
3320:
3310:
3308:
3303:
3302:
3298:
3288:
3286:
3281:
3280:
3276:
3266:
3264:
3259:
3258:
3254:
3244:
3242:
3237:
3236:
3232:
3222:
3220:
3215:
3214:
3210:
3194:
3193:
3186:
3184:
3179:
3178:
3174:
3166:
3162:
3161:
3157:
3148:
3147:
3143:
3135:
3131:
3130:
3126:
3118:
3114:
3113:
3109:
3101:
3097:
3096:
3092:
3083:
3079:
3049:
3045:
3036:
3035:
3031:
3021:
3019:
3015:
3014:
3007:
2968:
2964:
2954:
2952:
2948:
2947:
2932:
2919:
2918:
2914:
2904:
2902:
2897:
2896:
2892:
2882:
2880:
2870:
2866:
2856:
2854:
2844:
2837:
2827:
2825:
2816:
2815:
2811:
2801:
2799:
2788:
2784:
2774:
2772:
2761:
2757:
2747:
2745:
2741:
2740:
2736:
2726:
2724:
2720:
2719:
2715:
2699:
2698:
2691:
2689:
2680:
2679:
2675:
2659:
2658:
2651:
2649:
2646:www.eetimes.com
2640:
2639:
2635:
2627:
2623:
2622:
2618:
2608:
2606:
2597:
2596:
2592:
2581:
2577:
2567:
2565:
2561:
2560:
2556:
2503:
2499:
2484:
2480:
2470:
2468:
2463:
2462:
2458:
2436:
2434:
2419:
2415:
2402:
2401:
2397:
2392:
2387:
2386:
2377:
2373:
2364:
2360:
2351:
2333:
2329:
2322:
2320:
2316:
2311:
2306:
2212:
2089:(PBX) software.
1890:
1879:
1856:application by
1830:
1748:
1713:
1709:
1662:
1635:interconnection
1606:
1586:
1565:
1537:
1497:
1485:
1473:
1468:
1449:
1429:
1398:
1392:
1389:
1386:
1377:
1373:
1366:
1358:
1342:
1330:
1265:(SRTP) and the
1193:
1164:
1128:
1065:
1063:Emergency calls
1035:
1016:email addresses
977:
966:
960:
957:
946:
934:
923:
903:
835:data link layer
831:
792:
677:queueing delays
640:
598:
572:
552:
509:
487:
429:
427:Consumer market
424:
311:synchronization
241:
219:In addition to
134:stereo codecs.
100:
84:voice messaging
39:), also called
28:
23:
22:
15:
12:
11:
5:
6966:
6956:
6955:
6950:
6945:
6943:Videotelephony
6940:
6935:
6918:
6917:
6915:
6914:
6904:
6894:
6884:
6871:
6868:
6867:
6865:
6864:
6857:
6852:
6847:
6842:
6837:
6836:
6835:
6830:
6822:
6816:
6814:
6810:
6809:
6807:
6806:
6801:
6796:
6791:
6786:
6781:
6776:
6771:
6766:
6761:
6755:
6753:
6747:
6746:
6744:
6743:
6738:
6733:
6728:
6723:
6718:
6713:
6708:
6703:
6698:
6693:
6688:
6683:
6677:
6675:
6669:
6668:
6666:
6665:
6660:
6655:
6650:
6645:
6639:
6637:
6633:
6632:
6630:
6629:
6624:
6619:
6614:
6609:
6604:
6602:Space-division
6598:
6596:
6590:
6589:
6587:
6586:
6581:
6580:
6579:
6574:
6564:
6563:
6562:
6552:
6547:
6541:
6539:
6531:
6530:
6528:
6527:
6526:
6525:
6515:
6514:
6513:
6503:
6498:
6493:
6492:
6491:
6481:
6475:
6473:
6465:
6464:
6462:
6461:
6456:
6451:
6446:
6441:
6439:Camille Tissot
6436:
6431:
6426:
6421:
6416:
6414:Claude Shannon
6411:
6406:
6404:Tivadar Puskás
6401:
6396:
6391:
6386:
6381:
6376:
6374:Antonio Meucci
6371:
6366:
6361:
6356:
6351:
6346:
6344:Charles K. Kao
6341:
6336:
6331:
6326:
6321:
6319:Harold Hopkins
6316:
6311:
6306:
6301:
6296:
6291:
6286:
6281:
6276:
6271:
6266:
6261:
6256:
6251:
6246:
6241:
6236:
6231:
6226:
6221:
6219:Emile Berliner
6216:
6211:
6206:
6201:
6196:
6191:
6186:
6180:
6178:
6174:
6173:
6171:
6170:
6165:
6160:
6158:Videotelephony
6155:
6150:
6149:
6148:
6143:
6133:
6126:
6121:
6115:
6110:
6105:
6100:
6095:
6094:
6093:
6088:
6083:
6073:
6072:
6071:
6061:
6056:
6054:Radiotelephone
6051:
6046:
6041:
6036:
6031:
6026:
6021:
6020:
6019:
6009:
6004:
5999:
5994:
5989:
5984:
5979:
5974:
5969:
5964:
5959:
5958:
5957:
5952:
5947:
5942:
5940:Internet video
5932:
5931:
5930:
5925:
5920:
5915:
5905:
5900:
5895:
5890:
5885:
5880:
5874:
5872:
5866:
5865:
5858:
5857:
5850:
5843:
5835:
5826:
5825:
5803:
5800:
5799:
5797:
5796:
5791:
5786:
5781:
5776:
5770:
5768:
5764:
5763:
5761:
5760:
5755:
5750:
5748:Misdialed call
5745:
5739:
5737:
5733:
5732:
5730:
5729:
5724:
5719:
5714:
5709:
5704:
5699:
5694:
5689:
5684:
5678:
5676:
5672:
5671:
5669:
5668:
5663:
5657:
5655:
5651:
5650:
5648:
5647:
5642:
5637:
5632:
5627:
5621:
5619:
5615:
5614:
5607:
5606:
5599:
5592:
5584:
5575:
5574:
5572:
5571:
5566:
5561:
5555:
5553:
5549:
5548:
5546:
5545:
5540:
5535:
5534:
5533:
5523:
5518:
5513:
5508:
5503:
5498:
5492:
5490:
5484:
5483:
5481:
5480:
5475:
5470:
5469:
5468:
5463:
5456:Internet forum
5453:
5448:
5443:
5438:
5432:
5430:
5424:
5423:
5421:
5420:
5415:
5410:
5405:
5400:
5395:
5389:
5386:
5385:
5378:
5377:
5370:
5363:
5355:
5349:
5348:
5337:
5321:
5320:External links
5318:
5315:
5314:
5285:
5255:
5229:
5207:
5188:
5162:
5155:
5149:. p. 69.
5131:
5105:
5098:
5080:
5063:Fraunhofer IIS
5043:
5026:Fraunhofer IIS
5006:
4999:
4993:. p. 55.
4975:
4949:
4927:
4905:
4892:
4870:
4848:
4818:
4796:
4778:Keating, Tom.
4770:
4754:"MTALK-Readme"
4745:
4711:
4692:
4662:
4651:on May 7, 2006
4636:
4625:(5): 637–648.
4602:
4591:
4572:
4515:
4494:(4): 203–303.
4462:
4448:
4429:
4407:
4381:
4359:
4337:
4318:
4292:
4272:
4260:
4221:
4195:
4169:
4143:
4117:
4091:
4065:
4039:
4013:
3999:
3973:
3959:
3926:
3904:
3880:
3868:
3842:
3830:
3802:
3777:
3759:
3729:
3699:
3682:10.1.1.219.633
3656:
3647:SANS Institute
3633:
3600:
3572:
3548:
3522:
3492:
3470:
3444:
3405:
3375:
3345:
3338:
3318:
3296:
3274:
3252:
3230:
3208:
3172:
3155:
3141:
3124:
3107:
3090:
3077:
3043:
3029:
3005:
2962:
2930:
2912:
2890:
2864:
2835:
2809:
2782:
2755:
2734:
2713:
2673:
2633:
2616:
2590:
2575:
2554:
2517:(1): 184–199.
2497:
2478:
2456:
2413:
2394:
2393:
2391:
2388:
2385:
2384:
2371:
2358:
2328:or as a word,
2313:
2312:
2310:
2307:
2305:
2304:
2302:VoIP recording
2299:
2294:
2289:
2287:Voice over LTE
2284:
2279:
2274:
2269:
2264:
2259:
2254:
2249:
2244:
2239:
2234:
2229:
2224:
2219:
2213:
2211:
2208:
2207:
2206:
2199:
2198:
2197:
2191:
2181:
2170:
2159:
2156:
2149:
2142:
2139:
2132:
2121:
2120:
2119:
2112:
2109:wideband audio
2090:
2069:
2059:
2048:
2047:
2046:
2040:
2037:
2024:
2023:
2022:
2008:
2005:Internet Phone
1995:
1989:
1982:
1974:
1967:
1964:
1958:Voice over ATM
1954:
1951:Bishnu S. Atal
1939:
1928:
1921:
1906:
1887:
1886:encoded voice.
1868:
1861:
1850:
1829:
1826:
1824:to telephony.
1822:cloud services
1773:Bishnu S. Atal
1702:digital speech
1666:packet network
1661:
1658:
1626:Interconnected
1605:
1602:
1585:
1582:
1581:
1580:
1577:
1569:
1562:
1559:
1556:
1536:
1533:
1496:
1493:
1484:
1481:
1472:
1469:
1467:
1461:
1453:European Union
1448:
1447:European Union
1445:
1428:
1425:
1400:
1399:
1380:
1378:
1371:
1365:
1362:
1357:
1354:
1341:
1338:
1329:
1326:
1283:point-to-point
1192:
1189:
1163:
1160:
1156:data integrity
1127:
1124:
1064:
1061:
1034:
1031:
979:
978:
937:
935:
928:
922:
919:
902:
899:
898:
897:
890:coaxial cables
871:
861:
839:physical layer
830:
827:
791:
788:
717:playout buffer
652:problems with
639:
636:
597:
594:
571:
568:
551:
548:
508:
505:
486:
483:
482:
481:
474:
463:
428:
425:
423:
420:
419:
418:
415:Skype protocol
412:
406:
400:
390:
380:
374:
368:
362:
356:
350:
344:
338:
336:videotelephony
321:
320:
314:
304:
298:
292:
280:
270:
249:open standards
240:
237:
214:federated VoIP
99:
96:
51:sessions over
26:
9:
6:
4:
3:
2:
6965:
6954:
6951:
6949:
6946:
6944:
6941:
6939:
6936:
6934:
6933:Voice over IP
6931:
6930:
6928:
6913:
6905:
6903:
6895:
6893:
6885:
6883:
6873:
6872:
6869:
6862:
6858:
6856:
6853:
6851:
6848:
6846:
6843:
6841:
6838:
6834:
6831:
6829:
6826:
6825:
6823:
6821:
6818:
6817:
6815:
6811:
6805:
6802:
6800:
6797:
6795:
6792:
6790:
6787:
6785:
6782:
6780:
6777:
6775:
6772:
6770:
6767:
6765:
6762:
6760:
6757:
6756:
6754:
6752:
6748:
6742:
6739:
6737:
6734:
6732:
6729:
6727:
6724:
6722:
6719:
6717:
6714:
6712:
6709:
6707:
6704:
6702:
6699:
6697:
6694:
6692:
6689:
6687:
6684:
6682:
6679:
6678:
6676:
6674:
6670:
6664:
6661:
6659:
6656:
6654:
6651:
6649:
6646:
6644:
6641:
6640:
6638:
6634:
6628:
6627:Code-division
6625:
6623:
6620:
6618:
6615:
6613:
6612:Time-division
6610:
6608:
6605:
6603:
6600:
6599:
6597:
6595:
6591:
6585:
6582:
6578:
6575:
6573:
6570:
6569:
6568:
6565:
6561:
6558:
6557:
6556:
6553:
6551:
6548:
6546:
6543:
6542:
6540:
6538:and switching
6536:
6532:
6524:
6521:
6520:
6519:
6516:
6512:
6509:
6508:
6507:
6504:
6502:
6499:
6497:
6494:
6490:
6489:optical fiber
6487:
6486:
6485:
6482:
6480:
6479:Coaxial cable
6477:
6476:
6474:
6472:
6466:
6460:
6457:
6455:
6452:
6450:
6447:
6445:
6442:
6440:
6437:
6435:
6432:
6430:
6427:
6425:
6422:
6420:
6417:
6415:
6412:
6410:
6407:
6405:
6402:
6400:
6397:
6395:
6394:Radia Perlman
6392:
6390:
6387:
6385:
6382:
6380:
6377:
6375:
6372:
6370:
6367:
6365:
6362:
6360:
6357:
6355:
6352:
6350:
6347:
6345:
6342:
6340:
6337:
6335:
6332:
6330:
6327:
6325:
6322:
6320:
6317:
6315:
6312:
6310:
6307:
6305:
6302:
6300:
6297:
6295:
6292:
6290:
6287:
6285:
6284:Lee de Forest
6282:
6280:
6279:Thomas Edison
6277:
6275:
6272:
6270:
6269:Donald Davies
6267:
6265:
6262:
6260:
6257:
6255:
6254:Claude Chappe
6252:
6250:
6247:
6245:
6242:
6240:
6237:
6235:
6232:
6230:
6227:
6225:
6222:
6220:
6217:
6215:
6212:
6210:
6207:
6205:
6202:
6200:
6197:
6195:
6192:
6190:
6187:
6185:
6182:
6181:
6179:
6175:
6169:
6166:
6164:
6161:
6159:
6156:
6154:
6151:
6147:
6144:
6142:
6139:
6138:
6137:
6134:
6132:
6131:
6127:
6125:
6122:
6119:
6116:
6114:
6111:
6109:
6106:
6104:
6101:
6099:
6098:Smoke signals
6096:
6092:
6089:
6087:
6084:
6082:
6079:
6078:
6077:
6076:Semiconductor
6074:
6070:
6067:
6066:
6065:
6062:
6060:
6057:
6055:
6052:
6050:
6047:
6045:
6042:
6040:
6037:
6035:
6032:
6030:
6027:
6025:
6022:
6018:
6015:
6014:
6013:
6010:
6008:
6005:
6003:
6000:
5998:
5995:
5993:
5990:
5988:
5985:
5983:
5980:
5978:
5975:
5973:
5970:
5968:
5965:
5963:
5960:
5956:
5953:
5951:
5948:
5946:
5943:
5941:
5938:
5937:
5936:
5935:Digital media
5933:
5929:
5926:
5924:
5921:
5919:
5916:
5914:
5911:
5910:
5909:
5906:
5904:
5901:
5899:
5896:
5894:
5891:
5889:
5886:
5884:
5881:
5879:
5876:
5875:
5873:
5871:
5867:
5863:
5856:
5851:
5849:
5844:
5842:
5837:
5836:
5833:
5823:
5813:
5801:
5795:
5792:
5790:
5787:
5785:
5782:
5780:
5777:
5775:
5772:
5771:
5769:
5765:
5759:
5756:
5754:
5753:Nuisance call
5751:
5749:
5746:
5744:
5741:
5740:
5738:
5734:
5728:
5725:
5723:
5720:
5718:
5715:
5713:
5710:
5708:
5705:
5703:
5700:
5698:
5695:
5693:
5692:Fibre-optical
5690:
5688:
5685:
5683:
5680:
5679:
5677:
5673:
5667:
5664:
5662:
5659:
5658:
5656:
5652:
5646:
5643:
5641:
5638:
5636:
5633:
5631:
5628:
5626:
5623:
5622:
5620:
5616:
5612:
5605:
5600:
5598:
5593:
5591:
5586:
5585:
5582:
5570:
5567:
5565:
5564:Microblogging
5562:
5560:
5557:
5556:
5554:
5550:
5544:
5541:
5539:
5536:
5532:
5529:
5528:
5527:
5526:Voice over IP
5524:
5522:
5519:
5517:
5514:
5512:
5511:LAN messenger
5509:
5507:
5504:
5502:
5499:
5497:
5494:
5493:
5491:
5489:
5485:
5479:
5476:
5474:
5471:
5467:
5464:
5462:
5459:
5458:
5457:
5454:
5452:
5449:
5447:
5444:
5442:
5439:
5437:
5434:
5433:
5431:
5429:
5425:
5419:
5416:
5414:
5411:
5409:
5406:
5404:
5401:
5399:
5396:
5394:
5391:
5390:
5387:
5383:
5376:
5371:
5369:
5364:
5362:
5357:
5356:
5353:
5346:
5342:
5338:
5336:at Wiktionary
5335:
5334:
5328:
5324:
5323:
5309:
5304:
5300:
5296:
5289:
5282:
5278:
5275:
5271:
5267:
5264:
5259:
5244:
5240:
5233:
5217:
5211:
5204:
5200:
5197:
5192:
5177:
5173:
5166:
5158:
5156:9780470377864
5152:
5148:
5144:
5143:
5135:
5120:
5116:
5109:
5101:
5095:
5091:
5084:
5069:
5065:
5064:
5056:
5055:
5047:
5032:
5028:
5027:
5019:
5018:
5010:
5002:
5000:9780470023631
4996:
4992:
4988:
4987:
4979:
4963:
4959:
4953:
4937:
4931:
4915:
4909:
4903:, March 1996.
4902:
4896:
4880:
4874:
4858:
4852:
4846:
4842:
4839:
4836:June 2, 1997
4835:
4831:
4828:
4822:
4806:
4800:
4781:
4774:
4759:. Sunsite.edu
4755:
4749:
4734:
4730:
4726:
4725:Network World
4722:
4715:
4707:
4703:
4696:
4685:September 14,
4680:
4676:
4669:
4667:
4650:
4646:
4640:
4632:
4628:
4624:
4620:
4613:
4606:
4600:
4595:
4588:
4587:
4579:
4577:
4557:
4553:
4549:
4545:
4541:
4537:
4533:
4526:
4519:
4511:
4507:
4502:
4497:
4493:
4489:
4482:
4475:
4473:
4471:
4469:
4467:
4451:
4449:9781118909706
4445:
4441:
4440:
4433:
4417:
4416:"Danny Cohen"
4411:
4396:
4392:
4385:
4374:September 21,
4369:
4363:
4347:
4341:
4334:
4330:
4327:
4322:
4311:September 21,
4307:
4303:
4296:
4288:
4284:
4283:
4276:
4270:
4264:
4257:
4250:September 19,
4242:
4235:
4228:
4226:
4209:
4205:
4199:
4184:
4180:
4173:
4158:
4154:
4147:
4132:
4128:
4121:
4105:
4101:
4095:
4079:
4075:
4069:
4053:
4049:
4043:
4032:September 20,
4028:
4024:
4017:
4009:
4003:
3987:
3983:
3977:
3969:
3963:
3944:
3937:
3930:
3914:
3908:
3897:
3890:
3884:
3877:
3872:
3856:
3852:
3846:
3839:
3834:
3823:September 27,
3819:
3812:
3806:
3795:September 26,
3791:
3787:
3781:
3773:
3769:
3763:
3747:
3743:
3739:
3733:
3714:
3710:
3706:
3702:
3696:
3692:
3688:
3683:
3678:
3674:
3667:
3660:
3652:
3648:
3644:
3637:
3626:
3622:
3618:
3611:
3604:
3593:
3589:
3582:
3576:
3565:
3558:
3552:
3537:
3533:
3526:
3515:September 21,
3510:
3506:
3502:
3496:
3488:
3484:
3480:
3474:
3459:
3455:
3448:
3429:
3425:
3418:
3412:
3410:
3393:
3389:
3385:
3379:
3363:
3359:
3355:
3349:
3341:
3335:
3331:
3330:
3322:
3306:
3300:
3284:
3278:
3262:
3256:
3240:
3234:
3218:
3212:
3204:
3198:
3182:
3176:
3165:
3159:
3151:
3145:
3134:
3128:
3117:
3111:
3100:
3094:
3087:
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3073:
3070:
3065:
3060:
3056:
3055:
3047:
3039:
3033:
3018:
3012:
3010:
3001:
2997:
2993:
2989:
2985:
2981:
2977:
2973:
2966:
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2945:
2943:
2941:
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2937:
2935:
2926:
2922:
2916:
2900:
2894:
2879:
2875:
2868:
2853:
2849:
2842:
2840:
2823:
2819:
2813:
2797:
2793:
2786:
2770:
2766:
2759:
2744:
2738:
2723:
2717:
2709:
2703:
2687:
2683:
2677:
2669:
2663:
2647:
2643:
2637:
2626:
2620:
2604:
2600:
2594:
2586:
2583:Omar, Ahmed.
2579:
2564:
2558:
2550:
2546:
2542:
2538:
2534:
2530:
2525:
2520:
2516:
2512:
2508:
2501:
2493:
2489:
2482:
2466:
2460:
2453:
2451:
2447:
2432:
2428:
2427:cse.wustl.edu
2424:
2417:
2409:
2405:
2399:
2395:
2381:
2375:
2368:
2362:
2355:
2354:
2345:
2325:
2318:
2314:
2303:
2300:
2298:
2295:
2293:
2290:
2288:
2285:
2283:
2280:
2278:
2275:
2273:
2270:
2268:
2265:
2263:
2260:
2258:
2255:
2253:
2250:
2248:
2245:
2243:
2240:
2238:
2235:
2233:
2230:
2228:
2225:
2223:
2220:
2218:
2217:Audio over IP
2215:
2214:
2204:
2200:
2195:
2192:
2189:
2185:
2184:
2182:
2179:
2175:
2171:
2168:
2164:
2160:
2157:
2154:
2150:
2147:
2143:
2140:
2137:
2133:
2130:
2126:
2122:
2117:
2113:
2110:
2107:
2103:
2099:
2095:
2091:
2088:
2085:
2081:
2077:
2073:
2070:
2067:
2063:
2062:
2060:
2057:
2053:
2049:
2044:
2041:
2038:
2035:
2031:
2028:
2027:
2025:
2020:
2016:
2012:
2009:
2006:
2002:
1999:
1998:
1996:
1994:
1990:
1987:
1983:
1979:
1975:
1972:
1968:
1965:
1963:
1959:
1955:
1952:
1948:
1944:
1940:
1937:
1933:
1929:
1926:
1922:
1919:
1915:
1911:
1907:
1904:
1900:
1896:
1888:
1885:
1877:
1873:
1869:
1866:
1862:
1859:
1855:
1851:
1848:
1844:
1840:
1836:
1832:
1831:
1825:
1823:
1819:
1815:
1811:
1807:
1803:
1799:
1795:
1794:Lior Haramaty
1791:
1786:
1780:
1778:
1774:
1770:
1766:
1762:
1758:
1754:
1746:
1742:
1738:
1734:
1731:
1730:speech coding
1727:
1723:
1719:
1707:
1703:
1699:
1694:
1692:
1688:
1684:
1680:
1676:
1671:
1667:
1657:
1655:
1651:
1646:
1644:
1640:
1636:
1631:
1627:
1624:Operators of
1622:
1620:
1616:
1612:
1604:United States
1601:
1599:
1595:
1591:
1578:
1575:
1570:
1563:
1560:
1557:
1554:
1553:
1552:
1549:
1546:
1545:VoIP gateways
1542:
1532:
1530:
1526:
1522:
1518:
1513:
1511:
1506:
1502:
1492:
1490:
1480:
1478:
1466:
1460:
1456:
1454:
1444:
1442:
1438:
1434:
1424:
1422:
1418:
1414:
1410:
1405:
1396:
1384:
1379:
1370:
1369:
1361:
1353:
1351:
1347:
1337:
1335:
1325:
1323:
1319:
1314:
1312:
1308:
1304:
1300:
1294:
1292:
1288:
1284:
1280:
1276:
1272:
1269:protocol for
1268:
1264:
1259:
1257:
1253:
1249:
1245:
1241:
1237:
1232:
1229:
1225:
1221:
1216:
1214:
1210:
1206:
1202:
1198:
1188:
1185:
1181:
1177:
1172:
1169:
1159:
1157:
1151:
1149:
1144:
1139:
1137:
1133:
1123:
1121:
1117:
1113:
1109:
1104:
1102:
1098:
1093:
1090:
1086:
1081:
1079:
1073:
1070:
1060:
1056:
1054:
1049:
1047:
1043:
1039:
1030:
1028:
1023:
1021:
1017:
1013:
1009:
1005:
1001:
997:
993:
989:
986:
975:
972:
964:
961:November 2019
954:
950:
944:
943:
938:This section
936:
932:
927:
926:
918:
916:
912:
908:
895:
891:
887:
883:
879:
876:
872:
869:
865:
862:
859:
855:
851:
848:
847:
846:
844:
840:
836:
826:
822:
820:
816:
812:
808:
803:
801:
797:
787:
785:
780:
776:
771:
769:
765:
761:
757:
753:
748:
746:
742:
738:
734:
728:
726:
722:
718:
714:
713:queuing delay
710:
705:
703:
699:
693:
690:
686:
682:
678:
673:
671:
667:
661:
659:
655:
650:
646:
635:
633:
628:
626:
621:
617:
615:
606:
602:
593:
589:
587:
582:
580:
576:
567:
565:
561:
556:
547:
545:
541:
538:
533:
531:
527:
521:
519:
515:
507:Corporate use
504:
502:
498:
496:
492:
478:
475:
472:
468:
464:
461:
457:
453:
452:
451:
448:
446:
442:
433:
416:
413:
410:
407:
404:
401:
398:
394:
391:
388:
384:
381:
378:
375:
372:
369:
366:
363:
360:
357:
354:
351:
348:
345:
342:
339:
337:
333:
329:
326:
325:
324:
318:
315:
312:
308:
305:
302:
299:
296:
293:
290:
289:call progress
286:
285:
281:
278:
274:
271:
268:
264:
261:
260:
259:
256:
254:
250:
246:
236:
234:
230:
226:
222:
217:
215:
211:
207:
202:
200:
196:
192:
188:
184:
180:
176:
172:
168:
164:
160:
156:
152:
148:
144:
140:
139:speech coding
135:
133:
132:high-fidelity
129:
125:
121:
117:
113:
109:
105:
95:
93:
89:
85:
81:
77:
73:
69:
65:
60:
58:
54:
50:
46:
42:
38:
34:
30:
19:
6594:Multiplexing
6469:Transmission
6434:Nikola Tesla
6424:Henry Sutton
6379:Samuel Morse
6309:Robert Hooke
6274:Amos Dolbear
6209:John Bardeen
6128:
6108:Telautograph
6012:Mobile phone
5967:Edholm's law
5950:social media
5883:Broadcasting
5789:Théâtrophone
5767:Applications
5726:
5675:Connectivity
5635:Mobile phone
5525:
5332:
5294:
5288:
5258:
5246:. Retrieved
5243:AppleInsider
5232:
5220:. Retrieved
5210:
5191:
5179:. Retrieved
5175:
5165:
5141:
5134:
5122:. Retrieved
5118:
5108:
5089:
5083:
5071:. Retrieved
5061:
5053:
5046:
5034:. Retrieved
5024:
5016:
5009:
4985:
4978:
4966:. Retrieved
4962:the original
4952:
4940:. Retrieved
4930:
4918:. Retrieved
4908:
4900:
4895:
4883:. Retrieved
4873:
4861:. Retrieved
4851:
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2252:Internet fax
2082:, the first
2072:Mark Spencer
2004:
1854:Packet voice
1818:Asterisk PBX
1806:softswitches
1802:Marian Croak
1781:
1695:
1683:packet voice
1663:
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1630:Enhanced 911
1625:
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1483:Saudi Arabia
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1248:traverse NAT
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1226:can perform
1217:
1209:authenticate
1194:
1180:cable modems
1173:
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1120:assisted GPS
1108:Enhanced 911
1105:
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218:
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181:versions of
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120:video codecs
116:audio codecs
101:
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6794:NPL network
6506:Radio waves
6444:Alfred Vail
6354:Hedy Lamarr
6339:Dawon Kahng
6299:Elisha Gray
6259:Yogen Dalal
6184:Nasir Ahmed
6118:Teleprinter
5982:Heliographs
5794:Video calls
5743:Missed call
5654:Accessories
5393:Online chat
5124:January 20,
5073:October 20,
5036:October 24,
4968:January 21,
4942:January 21,
4920:November 7,
4885:January 21,
4863:January 21,
4811:January 21,
4789:November 7,
4655:January 21,
4565:October 18,
4455:December 6,
4422:December 6,
4110:January 11,
4084:January 10,
4058:January 10,
3368:January 20,
3311:January 21,
3289:January 21,
3267:January 21,
3245:January 21,
3223:January 21,
3084:CableLabs,
2901:. skype.com
2748:January 30,
2727:January 30,
2568:January 24,
2494:(5): 11–19.
2367:DoS attacks
2267:Mobile VoIP
2176:introduces
2084:open source
1978:InSoft Inc.
1971:Frame Relay
1912:of the USC
1858:Danny Cohen
1812:, MGCP and
1679:Danny Cohen
1668:designs by
1650:US Congress
1590:South Korea
1584:South Korea
1346:hearing aid
1213:virtual PBX
1168:phone lines
1126:Fax support
1008:Skype names
907:packet loss
886:power lines
864:IEEE 802.1p
854:IEEE 802.11
819:IEEE 802.1p
790:DSL and ATM
681:packet loss
501:Smartphones
495:IP backhaul
389:transports.
332:online chat
229:mobile data
221:VoIP phones
210:Google Talk
191:open source
45:voice calls
6927:Categories
6840:Antarctica
6799:Toasternet
6721:Television
6204:Paul Baran
6136:Television
6120:(teletype)
6113:Telegraphy
6091:transistor
6069:Phryctoria
6039:Photophone
6017:Smartphone
6007:Mass media
5645:Photophone
5552:Publishing
5466:Imageboard
5308:1602.04845
5181:January 1,
4881:. R. Zakon
4879:"RFC 2235"
4352:August 16,
4188:January 9,
4162:January 9,
4136:January 9,
3838:VOIPSA.org
3187:October 4,
2524:1709.01320
2390:References
2146:PhoneGnome
2056:softswitch
1930:1985: The
1910:Jon Postel
1863:1974: The
1828:Milestones
1798:Alon Cohen
1670:Paul Baran
1510:Change.org
1393:April 2022
1275:softphones
1078:IP address
1040:(LNP) and
754:(QoS) and
145:(LPC) and
124:narrowband
6938:Broadband
6824:Americas
6813:Locations
6784:Internet2
6545:Bandwidth
6249:Vint Cerf
6146:streaming
6124:Telephone
6064:Semaphore
5955:streaming
5758:Phone tag
5666:Caller ID
5611:Telephony
5461:Textboard
5222:March 31,
4763:April 29,
4733:0887-7661
4552:212485331
4544:2277-128X
4510:1932-8346
4214:March 26,
4157:Gulf News
3992:April 29,
3677:CiteSeerX
2992:1089-7089
2905:March 16,
2541:1932-4537
2437:March 19,
2118:standard.
2078:develops
2036:standard.
2019:Radvision
2015:Microsoft
2003:releases
1962:StrataCom
1918:Vint Cerf
1728:(LPC), a
1720:of early
1718:bandwidth
1621:(CALEA).
1423:company.
1334:caller ID
1328:Caller ID
1322:endpoints
1291:Wireshark
1236:firewalls
1116:VoIP E911
1069:land line
913:, packet
909:, packet
477:Softphone
399:instances
387:WebSocket
284:Signaling
267:transport
239:Protocols
189:, and an
169:(used in
161:(used in
153:(used in
104:telephony
6892:Category
6779:Internet
6769:CYCLADES
6686:Ethernet
6636:Concepts
6560:terminal
6511:wireless
6334:Bob Kahn
6177:Pioneers
6002:Internet
5893:Cable TV
5625:Landline
5538:Web chat
5277:Archived
5266:Archived
5199:Archived
4841:Archived
4830:Archived
4807:. iLocus
4400:March 2,
4329:Archived
4052:BBC News
3952:April 7,
3752:June 12,
3722:June 12,
3651:Archived
3625:Archived
3541:April 5,
3536:CircleID
3463:July 19,
3398:July 19,
3392:Archived
3197:cite web
3000:12336090
2883:March 3,
2857:March 2,
2822:Archived
2775:June 21,
2702:cite web
2692:April 8,
2662:cite web
2652:April 8,
2609:July 19,
2297:VoIP VPN
2292:VoiceXML
2210:See also
2186:Rise of
2178:FaceTime
2125:INOC-DBA
2080:Asterisk
2001:VocalTec
1986:VocalTec
1790:VocalTec
1785:Internet
1706:bit rate
1529:FaceTime
1521:WhatsApp
1417:Ethiopia
1409:captured
1191:Security
1130:Sending
894:contract
868:Ethernet
670:DiffServ
605:Asterisk
491:backhaul
456:Ethernet
422:Adoption
317:Security
235:system.
163:WhatsApp
155:FaceTime
98:Overview
94:(POTS).
57:Internet
6912:Commons
6902:Outline
6855:Oceania
6774:FidoNet
6759:ARPANET
6572:circuit
6141:digital
5870:History
5446:FidoNet
5283:in PDF)
5248:June 9,
4859:. ITU-T
4326:GPO.gov
4078:Reuters
3876:FCC.gov
3861:July 9,
3285:. Skype
3241:. Skype
2828:May 29,
2802:May 28,
2549:3873601
2471:May 11,
2380:802.3ah
2324:V-O-I-P
2282:UNIStim
2153:G.729.1
2106:G.722.1
2052:Level 3
1876:ARPANET
1691:ARPANET
1660:History
1643:nomadic
1499:In the
1451:In the
1383:updated
1311:SIPRNet
1258:(ICE).
1220:hackers
1205:encrypt
1176:routers
985:Class 5
915:latency
829:Layer 2
725:dropout
654:latency
277:session
263:Network
6850:Europe
6820:Africa
6804:Usenet
6764:BITNET
6701:Mobile
6577:packet
6086:MOSFET
6081:device
5878:Beacon
5516:Talker
5451:Usenet
5153:
5096:
4997:
4731:
4550:
4542:
4508:
4446:
4395:Forbes
3709:402760
3707:
3697:
3679:
3437:May 2,
3336:
3022:May 3,
2998:
2990:
2955:May 3,
2878:Forbes
2852:Forbes
2547:
2539:
2452:(SSL).
2404:"VoIP"
2201:2012:
2188:WebRTC
2183:2011:
2172:2010:
2161:2009:
2151:2006:
2144:2005:
2134:2003:
2123:2001:
2116:AAC-LD
2076:Digium
2061:1999:
2050:1997:
2026:1996:
1997:1995:
1976:1992:
1941:1985:
1936:NSFNET
1923:1981:
1916:, and
1897:, and
1891:
1880:
1870:1974:
1852:1973:
1849:(NTT).
1833:1966:
1755:, and
1749:
1722:modems
1714:
1710:
1700:(PCM)
1527:, and
1435:, the
1433:Canada
1427:Canada
1413:Panama
1136:codecs
911:jitter
777:
658:jitter
575:Hosted
564:Hosted
480:input.
409:Jingle
328:Matrix
151:AAC-LD
70:, and
6833:South
6828:North
6789:JANET
6726:Telex
6716:Radio
6555:Nodes
6550:Links
6471:media
6049:Radio
6034:Pager
5962:Drums
5928:video
5923:image
5913:audio
5736:Calls
5618:Types
5436:Email
5303:arXiv
5058:(PDF)
5021:(PDF)
4783:(PDF)
4757:(TXT)
4615:(PDF)
4559:(PDF)
4548:S2CID
4528:(PDF)
4484:(PDF)
4244:(PDF)
4237:(PDF)
3946:(PDF)
3939:(PDF)
3899:(PDF)
3892:(PDF)
3814:(PDF)
3716:(PDF)
3705:S2CID
3669:(PDF)
3628:(PDF)
3613:(PDF)
3595:(PDF)
3584:(PDF)
3567:(PDF)
3560:(PDF)
3431:(PDF)
3420:(PDF)
3388:ITWeb
3167:(PDF)
3136:(PDF)
3119:(PDF)
3102:(PDF)
2996:S2CID
2628:(PDF)
2545:S2CID
2519:arXiv
2309:Notes
2174:Apple
2167:Skype
2136:Skype
2102:Siren
2043:G.729
2034:H.323
2030:ITU-T
2011:Intel
1993:Linux
1882:kpbs
1810:H.323
1716:kbps
1708:of 64
1541:India
1535:India
1525:Skype
1505:Skype
1441:9-1-1
1279:IPsec
1132:faxes
1004:Skype
1000:E.164
992:E.164
875:ITU-T
815:VDSL2
768:H.248
764:H.323
614:below
579:Cloud
560:Cloud
544:Skype
530:Wi-Fi
460:Wi-Fi
359:H.248
347:H.323
301:Media
225:Wi-Fi
206:Skype
199:G.729
187:G.722
183:G.711
179:A-law
175:ÎĽ-law
171:Skype
6845:Asia
6731:UUCP
6691:ISDN
5727:VoIP
5717:PSTN
5712:POTS
5702:ISDN
5569:Wiki
5559:Blog
5333:VoIP
5250:2010
5224:2009
5183:2015
5151:ISBN
5126:2009
5094:ISBN
5075:2019
5038:2019
4995:ISBN
4970:2009
4944:2009
4922:2007
4887:2009
4865:2009
4813:2009
4791:2007
4765:2012
4740:2012
4729:ISSN
4687:2021
4657:2009
4567:2019
4540:ISSN
4506:ISSN
4457:2014
4444:ISBN
4424:2014
4402:2009
4376:2017
4354:2014
4313:2017
4252:2012
4216:2020
4208:CNBC
4190:2018
4164:2018
4138:2018
4112:2018
4086:2018
4060:2018
4034:2016
3994:2017
3954:2008
3921:2006
3863:2019
3825:2023
3797:2022
3754:2009
3724:2009
3695:ISBN
3543:2006
3517:2017
3465:2022
3439:2011
3400:2022
3370:2009
3334:ISBN
3313:2009
3291:2009
3269:2009
3247:2009
3225:2009
3203:link
3189:2012
3072:3611
3024:2011
2988:ISSN
2957:2011
2907:2009
2885:2009
2859:2009
2830:2009
2804:2009
2777:2011
2750:2018
2729:2018
2708:link
2694:2015
2668:link
2654:2015
2611:2022
2570:2020
2537:ISSN
2473:2012
2439:2024
2352:VOYP
2203:Opus
2194:CELT
2163:SILK
2064:The
2017:and
1949:and
1925:IPv4
1884:CVSD
1796:and
1771:and
1477:Oman
1471:Oman
1303:ZRTP
1301:and
1299:SRTP
1267:ZRTP
1254:and
1252:STUN
1238:and
1207:and
1143:T.38
878:G.hn
873:The
837:and
813:and
811:VDSL
779:3611
679:and
265:and
195:iLBC
177:and
167:SILK
159:Opus
126:and
118:and
37:VoIP
18:VOIP
6736:WAN
6706:NGN
6696:LAN
5977:Fax
5918:DCT
4627:doi
4496:doi
3687:doi
3424:FCC
3358:FCC
3069:RFC
3059:doi
2980:doi
2529:doi
2129:SIP
2074:of
1901:in
1841:of
1759:in
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1475:In
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