ISO/IEC 21558-1:2022 システム間の通信と情報交換—将来のネットワークアーキテクチャ— Part 1: スイッチングとルーティング | ページ 2

Foreword

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This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 6, Telecommunications and information exchange between systems.

A list of all parts in the ISO/IEC 21558 series can be found on the ISO and IEC websites.

Introduction

ISO/IEC TR 29181-1 describes the definition, general concept, problems and requirements for the Future Network (FN).

ISO/IEC TR 29181-3 examines the requirements for carrying data over digital networks and identifies the requirements that are not satisfied by the current Internet. It also notes some expected characteristics of new systems that are better able to satisfy the requirements and specifies a model which supports both the existing system and the new systems. This will enable a migration to the new systems; it is also intended to make networks of all sizes easier to manage.

This document specifies the FN architecture which is designed to meet the requirements identified in ISO/IEC TR 29181-3. Protocols to support this architecture are specified in ISO/IEC 21559-1.

FN is a packet network which, as well as carrying data between computers, also meets the rather different requirements of live digital audio and video, which form an increasing proportion of the traffic on today's networks.

Whereas in IP all addressing information needs to be present in the packet headers, in FN the information needed to route packets is carried separately from the packets themselves. This reduces the size of the encapsulation by an order of magnitude and simplifies the process of forwarding the packets in switches.

Most importantly, it allows different addressing mechanisms to be used without changing the packet format and supports mobility without needing artificial devices such as IP-in-IP tunnels.

FN offers two main services: an ultra-low-latency “AV” service tailored to the needs of constant-bit-rate traffic such as audio and video, and a best-effort “IT” service suitable for the kind of unpredictable demand for which IP was intended. The AV service can also be used for file transfer ここで, it eliminates the need for the kind of empirical throughput testing that is a feature of TCP.

Some details of the services (particularly the slot size for the AV service, which was originally envisaged as being much more flexible) are a result of experimentation with a prototype implementation.

1 Scope

This document specifies the switching and routing architecture of the Future Network (FN).

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO/IEC TR 29181-1, ISO/IEC TR 29181-3 and the following apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

Bibliography