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Handshake (computing)

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362:, which typically negotiate communication parameters for a brief period when a connection is first established, and there after use those parameters to provide optimal information transfer over the channel as a function of its quality and capacity. The "squealing" (which is actually a sound that changes in pitch 100 times every second) noises made by some modems with speaker output immediately after a connection is established are in fact the sounds of modems at both ends engaging in a handshaking procedure; once the procedure is completed, the speaker might be silenced, depending on the settings of operating system or the application controlling the modem. 328:(SSL or TLS) connection starts, the record encapsulates a "control" protocol—the handshake messaging protocol (content type 22). This protocol is used to exchange all the information required by both sides for the exchange of the actual application data by TLS. It defines the messages formatting or containing this information and the order of their exchange. These may vary according to the demands of the client and server—i.e., there are several possible procedures to set up the connection. This initial exchange results in a successful TLS connection (both parties ready to transfer application data with TLS) or an alert message (as specified below). 165: 25: 293:
The reason for the client and server not using a default sequence number such as 0 for establishing the connection is to protect against two incarnations of the same connection reusing the same sequence number too soon, which means a segment from an earlier incarnation of a connection might interfere
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A simple handshaking protocol might only involve the receiver sending a message meaning "I received your last message and I am ready for you to send me another one." A more complex handshaking protocol might allow the sender to ask the receiver if it is ready to receive or for the receiver to reply
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In mobile device chargers offering special quick-charge abilities to supported devices, the charging process will switch up to a higher output voltage for increased power transfer. But this could cause serious damage to an unsupported device or even result in a fire. It is therefore very important
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or hardware features. Handshaking is a technique of communication between two entities. However, within TCP/IP RFCs, the term "handshake" is most commonly used to reference the TCP three-way handshake. For example, the term "handshake" is not present in RFCs covering FTP or SMTP. One exception is
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for the device and charger to first perform a handshake to "agree" on mutually supported charge parameters. If such a charger can't identify the connected device or determine its compatibility, it will default to normal but much slower charge parameters within the USB standard.
107:") through the exchange of information that establishes the protocols of a communication link at the start of the communication, before full communication begins. The handshaking process usually takes place in order to establish rules for communication when a 111:
attempts to communicate with another device. Signals are usually exchanged between two devices to establish a communication link. For example, when a computer communicates with another device such as a
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In this setup, the synchronize messages act as service requests from one server to the other, while the acknowledgement messages return to the requesting server to let it know the message was received.
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This frequently used term describes the use of RTS and CTS signals over a serial interconnection. It is, however, not quite correct; it's not a true form of handshaking, and is better described as
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Handshaking facilitates connecting relatively heterogeneous systems or equipment over a communication channel without the need for human intervention to set parameters.
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Transport Layer Security, TLS, setup, FTP RFC 4217. In place of the term "handshake", FTP RFC 3659 substitutes the term "conversation" for the passing of commands.
282: 253: 227: 200: 116:, the two devices will signal each other that they are switched on and ready to work, as well as to agree to which protocols are being used. 39: 746: 716: 119:
Handshaking can negotiate parameters that are acceptable to equipment and systems at both ends of the communication channel, including
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with a negative acknowledgement meaning "I did not receive your last message correctly, please resend it" (e.g., if the data was
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is a signal between two devices or programs, used to, e.g., authenticate, coordinate. An example is the handshaking between a
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The first host (Alice) sends the second host (Bob) a "synchronize" (SYN) message with its own sequence number
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The protocol is used to negotiate the secure attributes of a session. (RFC 5246, p. 37)
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Please expand the article to include this information. Further details may exist on the
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Alice replies with an acknowledgment (ACK) message with acknowledgement number
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This article is about the computer science term. For the greeting habit, see
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is an automated process of negotiation between two participants (example "
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to negotiate authentication, encryption and maximum message size.
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FTP 959, 3659 (conversation), 2228,4217 (TLS handshake),5797
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Jacaranda Information Processes and Technology: HSC Course
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The Transport Layer Security (TLS) Protocol, version 1.2
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For the mathematical lemma, see 14: 816: 481:TheFreeDictionary's Encyclopedia 334: 313: 168:Example of three way handshaking 23: 487: 469: 460: 451: 442: 417: 393: 1: 386: 366:Serial "Hardware Handshaking" 304:Simple Mail Transfer Protocol 7: 229:and acknowledgement number 10: 821: 341:WPA2 standard for wireless 317: 154: 69: 58: 704: 686: 658: 565: 121:information transfer rate 326:Transport Layer Security 85:and an application in a 297: 255:, which Alice receives. 160:TCP three-way handshake 378:Mobile device charging 278: 249: 223: 196: 172:Establishing a normal 169: 34:is missing information 351:Dial-up access modems 279: 250: 224: 202:, which Bob receives. 197: 167: 135:procedure, and other 800:Network architecture 308:includes handshaking 262: 233: 213: 186: 705:Long range wireless 277:{\displaystyle y+1} 248:{\displaystyle x+1} 274: 245: 219: 192: 170: 97:telecommunications 805:Network protocols 795:Data transmission 782: 781: 448:TCP RFC 793, 2581 345:IEEE 802.11i-2004 222:{\displaystyle y} 195:{\displaystyle x} 65:Handshaking lemma 57: 56: 812: 552: 545: 538: 529: 528: 522: 521: 512: 510:10.17487/RFC5246 491: 485: 484: 473: 467: 464: 458: 455: 449: 446: 440: 439: 421: 415: 414: 412: 411: 405:SearchNetworking 397: 283: 281: 280: 275: 254: 252: 251: 246: 228: 226: 225: 220: 201: 199: 198: 193: 77:In computing, a 52: 49: 43: 27: 19: 820: 819: 815: 814: 813: 811: 810: 809: 785: 784: 783: 778: 700: 682: 654: 561: 559:Internet access 556: 526: 525: 503:. 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Retrieved 404: 395: 381: 372:flow control 369: 354: 338: 330: 323: 301: 292: 171: 150: 142: 118: 100: 94: 78: 76: 45: 33: 148:en route). 789:Categories 752:Muni Wi-Fi 643:Power-line 410:2018-02-19 387:References 83:hypervisor 757:Satellite 668:Bluetooth 648:Broadband 623:IEEE 1901 146:corrupted 133:interrupt 123:, coding 101:handshake 79:handshake 61:Handshake 40:talk page 762:UMTS-TDD 613:HomePlug 593:Ethernet 137:protocol 125:alphabet 109:computer 618:HomePNA 578:Dial-up 357:dial-up 324:When a 207:SYN-ACK 155:Example 737:iBurst 608:Nessum 583:DOCSIS 432:  360:modems 129:parity 772:WiBro 767:WiMAX 712:5G NR 696:Wi-Fi 673:Li-Fi 573:Cable 566:Wired 114:modem 87:guest 747:MMDS 732:HSPA 727:GPRS 722:EVDO 717:DECT 633:MoCA 628:ISDN 603:G.hn 598:FTTx 518:5246 501:IETF 430:ISBN 339:The 302:The 298:SMTP 99:, a 742:LTE 638:PON 588:DSL 515:RFC 505:doi 174:TCP 95:In 791:: 513:. 499:. 479:. 403:. 374:. 347:. 131:, 127:, 92:. 551:e 544:t 537:v 520:. 507:: 483:. 438:. 413:. 272:1 269:+ 266:y 243:1 240:+ 237:x 217:y 190:x 74:. 67:. 50:) 46:( 42:.

Index


talk page
Handshake
Handshaking lemma
Autonegotiation
hypervisor
guest
virtual machine
telecommunications
Alice and Bob
computer
modem
information transfer rate
alphabet
parity
interrupt
protocol
corrupted

TCP
SYN-ACK
Simple Mail Transfer Protocol
includes handshaking
Transport Layer Security § TLS handshake
Transport Layer Security
WPA2 standard for wireless
IEEE 802.11i-2004
dial-up
modems
flow control

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