47:
829:. 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.
766:
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
742:
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
773:
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:
804:
Since many networks are partitioned into subnetworks and connect to other networks for wide-area communications, networks use specialized hosts, called gateways or
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984:"X.225 : Information technology – Open Systems Interconnection – Connection-oriented Session protocol: Protocol specification"
1146:, Hubert Zimmermann, IEEE Transactions on Communications, vol. 28, no. 4, April 1980, pp. 425 – 432. (PDF-Datei; 776 kB)
597:
140:
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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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35:
778:"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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1119:
277:
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185:
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OSI Reference Model—The ISO Model of
Architecture for Open Systems Interconnection
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787:"Fred Murphy, 1 Main Street, Dublin, Ireland" to people anywhere in the world.
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784:"Fred Murphy, 1 Main Street, Dublin" to people in Ireland,
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The following are examples of protocols operating at the network layer.
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781:"Fred Murphy, 1 Main Street" to Dubliners,
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The network layer provides the means of transferring variable-length
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30:"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
1107:
679:
8:
34:. For the layer in the cerebral cortex, see
909:Enhanced Interior Gateway Routing Protocol
845:packets that are larger than the smallest
833:Fragmentation of Internet Protocol packets
686:
672:
102:
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91:Learn how and when to remove this message
792:On the Internet, addresses are known as
753:Functions of the network layer include:
54:This article includes a list of general
36:Cerebral cortex § Layered_structure
975:
714:. The network layer is responsible for
105:
945:Low Latency Anonymous Routing Protocol
853:to fragment packets if needed, and of
808:, to forward packets between networks.
837:The network layer is responsible for
7:
990:from the original on 1 February 2021
891:Connectionless-mode Network Service
746:and issues service requests to the
921:Internet Group Management Protocol
60:it lacks sufficient corresponding
25:
915:Internet Control Message Protocol
857:to reassemble them if received.
45:
738:from a source to a destination
1116:Upper Saddle River, New Jersey
957:Protocol Independent Multicast
1:
1106:Tanenbaum, Andrew S. (2003).
963:Routing Information Protocol
939:Internetwork Packet Exchange
839:fragmentation and reassembly
758:Connectionless communication
27:Third layer of the OSI model
1176:
1097:.
927:Internet Protocol Security
897:Datagram Delivery Protocol
29:
1039:. Network Working Group.
903:Exterior Gateway Protocol
876:, instead of this layer.
951:Open Shortest Path First
813:Relation to TCP/IP model
75:more precise citations.
1033:, ed. (October 1989).
722:through intermediate
1061:Updated by RFC
1059:Internet Standard 3.
825:, located above the
796:(Internet Protocol).
704:computer networking
698:In the seven-layer
870:Path MTU discovery
801:Message forwarding
232:Presentation layer
1110:Computer networks
933:Internet Protocol
764:Internet Protocol
716:packet forwarding
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124:Application layer
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16:(Redirected from
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1049:. STD 3.
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762:For example,
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1014:. Retrieved
1004:
992:. Retrieved
978:
883:
868:. For this,
860:Conversely,
859:
836:
819:TCP/IP model
816:
794:IP addresses
752:
733:
711:
707:
697:
372:
215:
87:
81:October 2009
78:
59:
931:IPv4/IPv6,
866:packet loss
638:IEEE 802.16
633:IEEE 802.15
628:IEEE 802.11
552:IEEE 802.11
523:Frame Relay
73:introducing
1016:2017-05-11
970:References
827:link layer
718:including
623:IEEE 802.3
547:Q.922 LAPF
518:IEEE 802.3
498:IEEE 802.2
285:Named pipe
56:references
1160:OSI model
1031:R. Braden
1010:"Layer 3"
880:Protocols
730:Functions
700:OSI model
658:Bluetooth
643:IEEE 1394
603:SONET/SDH
564:1.
449:2.
427:AppleTalk
371:3.
325:4.
276:5.
230:6.
122:7.
107:OSI model
1154:Category
994:10 March
988:Archived
217:more....
943:LLARP,
925:IPsec,
907:EIGRP,
851:routers
806:routers
724:routers
720:routing
712:layer 3
290:NetBIOS
211:NETCONF
69:improve
18:Layer-3
1126:
949:OSPF,
919:IGMP,
913:ICMP,
889:CLNS,
767:model.
706:, the
578:RS-449
573:RS-232
540:
401:ICMPv6
201:Telnet
165:HTTP/3
156:Gopher
58:, but
961:RIP,
955:PIM,
937:IPX,
901:EGP,
895:DDP,
855:hosts
593:I.431
588:I.430
478:CSLIP
422:IS-IS
407:IPsec
314:X.225
310:SOCKS
254:ASCII
249:ASN.1
113:layer
1124:ISBN
1095:9293
1093:and
1091:8029
1087:6864
1083:6633
1079:6298
1075:6093
1071:5884
1067:4379
1063:1349
1054:1122
996:2023
862:IPv6
843:IPv4
841:for
817:The
740:host
542:LAPB
538:X.25
513:L2TP
493:PLIP
483:SLIP
473:HDLC
468:SDLC
432:X.25
412:IGMP
397:ICMP
390:IPv6
385:IPv4
354:QUIC
349:DCCP
344:SCTP
300:PPTP
239:MIME
206:DHCP
196:SNMP
191:SMTP
181:SMPP
161:HTTP
131:NNTP
1051:RFC
1041:doi
847:MTU
710:is
702:of
653:USB
618:DSL
613:OTN
608:PON
598:PDH
533:PPP
508:MAC
503:LLC
488:GFP
463:ARP
458:ATM
437:PLP
417:IPX
359:SPX
339:UDP
334:TCP
305:RTP
295:SAP
264:PGP
259:TLS
244:XDR
186:SSH
176:NTP
171:NFS
151:FTP
146:DNS
141:SSI
136:SIP
111:by
32:MP3
1156::
1122:.
1118::
1114:.
1089:,
1085:,
1081:,
1077:,
1073:,
1069:,
1065:,
986:.
750:.
726:.
380:IP
1132:.
1056:.
1043::
1019:.
998:.
687:e
680:t
673:v
403:)
399:(
167:)
163:(
94:)
88:(
83:)
79:(
65:.
38:.
20:)
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