36:
818:. In many textbooks and other secondary references, the TCP/IP Internet layer is equated with the OSI network layer. However, this comparison is misleading, as the allowed characteristics of protocols (e.g., whether they are connection-oriented or connection-less) placed into these layers are different in the two models. The TCP/IP Internet layer is in fact only a subset of functionality of the network layer. It describes only one type of network architecture, the Internet.
755:
is connectionless, in that a data packet can travel from a sender to a recipient without the recipient having to send an acknowledgement. Connection-oriented protocols exist at other, higher layers of the OSI
933:
731:
via one or more networks. Within the service layering semantics of the OSI (Open
Systems Interconnection) network architecture, the network layer responds to service requests from the
762:
Every host in the network must have a unique address that determines where it is. This address is normally assigned from a hierarchical system. For example, you can be:
793:
Since many networks are partitioned into subnetworks and connect to other networks for wide-area communications, networks use specialized hosts, called gateways or
897:
973:"X.225 : Information technology – Open Systems Interconnection – Connection-oriented Session protocol: Protocol specification"
1135:, Hubert Zimmermann, IEEE Transactions on Communications, vol. 28, no. 4, April 1980, pp. 425 – 432. (PDF-Datei; 776 kB)
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packets are not fragmented during forwarding, but the MTU supported by a specific path must still be established, to avoid
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of all the intermediate links on the packet's path to its destination. It is the function of
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767:"Fred Murphy" to people in your house,
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describes the protocols used by the
Internet. The TCP/IP model has a layer called the
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OSI Reference Model—The ISO Model of
Architecture for Open Systems Interconnection
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776:"Fred Murphy, 1 Main Street, Dublin, Ireland" to people anywhere in the world.
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The following are examples of protocols operating at the network layer.
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The network layer provides the means of transferring variable-length
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19:"Layer 3" redirects here. For the MPEG-1 Audio format, see
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Requirements for
Internet Hosts -- Communication Layers
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is used between endpoints, which makes it part of the
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23:. For the layer in the cerebral cortex, see
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898:Enhanced Interior Gateway Routing Protocol
834:packets that are larger than the smallest
822:Fragmentation of Internet Protocol packets
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661:
1094:
1033:
1018:
80:Learn how and when to remove this message
781:On the Internet, addresses are known as
742:Functions of the network layer include:
43:This article includes a list of general
25:Cerebral cortex § Layered_structure
703:. The network layer is responsible for
1141:
1012:
934:Low Latency Anonymous Routing Protocol
842:to fragment packets if needed, and of
797:, to forward packets between networks.
826:The network layer is responsible for
979:from the original on 1 February 2021
29:
880:Connectionless-mode Network Service
735:and issues service requests to the
13:
910:Internet Group Management Protocol
49:it lacks sufficient corresponding
14:
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904:Internet Control Message Protocol
846:to reassemble them if received.
34:
727:from a source to a destination
1105:Upper Saddle River, New Jersey
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965:
946:Protocol Independent Multicast
1:
1095:Tanenbaum, Andrew S. (2003).
958:
952:Routing Information Protocol
928:Internetwork Packet Exchange
868:
828:fragmentation and reassembly
747:Connectionless communication
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16:Third layer of the OSI model
7:
10:
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1086:.
916:Internet Protocol Security
886:Datagram Delivery Protocol
18:
1028:. Network Working Group.
892:Exterior Gateway Protocol
865:, instead of this layer.
940:Open Shortest Path First
802:Relation to TCP/IP model
64:more precise citations.
1022:, ed. (October 1989).
711:through intermediate
1050:Updated by RFC
1048:Internet Standard 3.
814:, located above the
785:(Internet Protocol).
693:computer networking
687:In the seven-layer
859:Path MTU discovery
790:Message forwarding
221:Presentation layer
1099:Computer networks
922:Internet Protocol
753:Internet Protocol
705:packet forwarding
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113:Application layer
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1024:
1014:
1003:. Retrieved
993:
981:. Retrieved
967:
872:
857:. For this,
849:Conversely,
848:
825:
808:TCP/IP model
805:
783:IP addresses
741:
722:
700:
696:
686:
361:
204:
76:
70:October 2009
67:
48:
920:IPv4/IPv6,
855:packet loss
627:IEEE 802.16
622:IEEE 802.15
617:IEEE 802.11
541:IEEE 802.11
512:Frame Relay
62:introducing
1005:2017-05-11
959:References
816:link layer
707:including
612:IEEE 802.3
536:Q.922 LAPF
507:IEEE 802.3
487:IEEE 802.2
274:Named pipe
45:references
1149:OSI model
1020:R. Braden
999:"Layer 3"
869:Protocols
719:Functions
689:OSI model
647:Bluetooth
632:IEEE 1394
592:SONET/SDH
553:1.
438:2.
416:AppleTalk
360:3.
314:4.
265:5.
219:6.
111:7.
96:OSI model
1143:Category
983:10 March
977:Archived
206:more....
932:LLARP,
914:IPsec,
896:EIGRP,
840:routers
795:routers
713:routers
709:routing
701:layer 3
279:NetBIOS
200:NETCONF
58:improve
1115:
938:OSPF,
908:IGMP,
902:ICMP,
878:CLNS,
756:model.
695:, the
567:RS-449
562:RS-232
529:
390:ICMPv6
190:Telnet
154:HTTP/3
145:Gopher
47:, but
950:RIP,
944:PIM,
926:IPX,
890:EGP,
884:DDP,
844:hosts
582:I.431
577:I.430
467:CSLIP
411:IS-IS
396:IPsec
303:X.225
299:SOCKS
243:ASCII
238:ASN.1
102:layer
1113:ISBN
1084:9293
1082:and
1080:8029
1076:6864
1072:6633
1068:6298
1064:6093
1060:5884
1056:4379
1052:1349
1043:1122
985:2023
851:IPv6
832:IPv4
830:for
806:The
729:host
531:LAPB
527:X.25
502:L2TP
482:PLIP
472:SLIP
462:HDLC
457:SDLC
421:X.25
401:IGMP
386:ICMP
379:IPv6
374:IPv4
343:QUIC
338:DCCP
333:SCTP
289:PPTP
228:MIME
195:DHCP
185:SNMP
180:SMTP
170:SMPP
150:HTTP
120:NNTP
1040:RFC
1030:doi
836:MTU
699:is
691:of
642:USB
607:DSL
602:OTN
597:PON
587:PDH
522:PPP
497:MAC
492:LLC
477:GFP
452:ARP
447:ATM
426:PLP
406:IPX
348:SPX
328:UDP
323:TCP
294:RTP
284:SAP
253:PGP
248:TLS
233:XDR
175:SSH
165:NTP
160:NFS
140:FTP
135:DNS
130:SSI
125:SIP
100:by
21:MP3
1145::
1111:.
1107::
1103:.
1078:,
1074:,
1070:,
1066:,
1062:,
1058:,
1054:,
975:.
739:.
715:.
369:IP
1121:.
1045:.
1032::
1008:.
987:.
676:e
669:t
662:v
392:)
388:(
156:)
152:(
83:)
77:(
72:)
68:(
54:.
27:.
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