Internet protocol suite

ja: インターネット・プロトコル・スイート

参照モデルというよりは network architecture だろう

参照モデル: TCP/IP model

モデルとしてはイマイチ

タネンバウムいわく

以下の 4階層も、曖昧模糊としてて、モデルとしては利用しづらい。

欠点: service, interface, protocol の区別がない。

layers

階層は 4層で整理する。

Link layer

これは層ではなく interface である。

by タネンバウム §1.6.4

物理層との分離がない。

同上

Internet layer

Transport layer

Application layer

しかし、その境界は厳密ではない。

あくまでも、機能ベース。

下位に依存するからと言って、直上の上位に置かないといけないワケではない。

ref. Chao, Lee (2009-12-21) (英語). Networking Systems Design and Development. CRC Press. ISBN 978-1-4200-9160-1. §2.4.5 Internet Routing Protocols. p. 45: https://books.google.com/books?id=MyzNBQAAQBAJ&newbks=0&printsec=frontcover&pg=PA45

The Internet layer includes several Internet routing protocols such as Rooting Information Protocol (RIP), Open Shortest Path First (OSPF) protocol, and Border Gateway Protocol (BCP). These protocols are used to create and update routing tables, which store information about the routes from one network to other networks on the Internet. The routing protocols can also be used to calculate the best path from one network to another and advertise routes for dynamic routing.

ref. Chao, Lee (2015-09-22) (英語). Cloud Computing Networking: Theory, Practice, and Development. CRC Press. ISBN 978-1-4822-5482-2. §2.4 Internet Layer Protocols. p. 46: https://books.google.com/books?id=dtyYCgAAQBAJ&newbks=0&printsec=frontcover&pg=PA46

In the TCP/IP architecture, protocols in the Internet layer are used to deliver packets from a source host to a destination host across a network. The IP is a well-known Internet layer protocol. It is the core protocol in the TCP/IP architecture. IP is the protocol that carries packets to the destination host. The journey may cross various types of networks. Another significant Internet layer protocol is the Internet Control Message Protocol (ICMP) used by network operating systems to get responses from remote hosts. The Address Resolution Protocol (ARP) relates an IP address with its hardware address, and IP Security (IPSec) is for securing IP communication. There is an argument on which layer the routing protocols should belong to. Since BGP and RIP use UDP in data transmission, some authors think BGP and RIP should belong to the application layer. Since OSPF uses IP in data transmission, some authors believe OSPF should belong to the transport layer. Sometimes, OSPF is listed in the network interface layer. Also, some authors think ARP should belong to the network interface layer. So far, there is no convincing answer to the argument. Here, for convenience, these protocols will be described in the Internet layer.

インターネット層のプロトコルは、ネットワーク上で送信元ホストから送信先ホストにパケットを配信するために使用されます。

今のところ、この議論に対する説得力のある答えはありません。ここでは、便宜上、これらのプロトコルはインターネット層で記述することにします。

ref. Mário Marques da Silva (2018) Cable and Wireless Networks: Theory and Practice - Google Books (11.4 Adaptive Routing Algorithms and Protocols, p. 308)

Although the exchange of data generated by some routing protocols to allow the creation of routing tables is carried out over UDP datagrams, routing protocols such as the RIP, the OSPF, the legacy IGRP, the EIGRP, and the 18-13 belong to the Internet layer (layer 3). As can be seen from Figure 11.1], in case of the RIP, there is a lower layer protocol (routing protocol) invoking a higher layer protocol (transport protocol—UDP). This is possible in TCP/IP stack, while the OSI reference model only allows an upper layer to make use of the services provided by a lower layer (and not the reverse).

OSI参照モデルでは上位層は下位層が提供するサービスを利用することしかできません（逆はできません）。

要は、同レイヤーや上位レイヤーのプロトコルを使っても良い。

FIGURE 11.11 Example of some protocols and technologies used by different TCP/IP layers.

https://gyazo.com/b8e80c1697ea8dea3eaaf91083bdc1f9

ref. Mário Marques da Silva (2018) Cable and Wireless Networks: Theory and Practice - Google Books (11.4 Adaptive Routing Algorithms and Protocols, p. 308)

protocols

per layers

application

HTTP

DNS

transport

TCP