Browse Prior Art Database

The Multi-Class Extension to Multi-Link PPP (RFC2686)

IP.com Disclosure Number: IPCOM000003278D
Original Publication Date: 1999-Sep-01
Included in the Prior Art Database: 2000-Sep-13
Document File: 9 page(s) / 22K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

C. Bormann: AUTHOR

Abstract

A companion document describes an architecture for providing integrated services over low-bitrate links, such as modem lines, ISDN B-channels, and sub-T1 links [1]. The main components of the architecture are: a real-time encapsulation format for asynchronous and synchronous low-bitrate links, a header compression architecture optimized for real-time flows, elements of negotiation protocols used between routers (or between hosts and routers), and announcement protocols used by applications to allow this negotiation to take place.

This text was extracted from a ASCII document.
This is the abbreviated version, containing approximately 12% of the total text.

Network Working Group C. Bormann

Request for Comments: 2686 Universitaet Bremen TZI

Category: Standards Track September 1999

The Multi-Class Extension to Multi-Link PPP

Status of this Memo

This document specifies an Internet standards track protocol for the

Internet community, and requests discussion and suggestions for

improvements. Please refer to the current edition of the "Internet

Official Protocol Standards" (STD 1) for the standardization state

and status of this protocol. Distribution of this memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (1999). All Rights Reserved.

Abstract

A companion document describes an architecture for providing

integrated services over low-bitrate links, such as modem lines, ISDN

B-channels, and sub-T1 links [1]. The main components of the

architecture are: a real-time encapsulation format for asynchronous

and synchronous low-bitrate links, a header compression architecture

optimized for real-time flows, elements of negotiation protocols used

between routers (or between hosts and routers), and announcement

protocols used by applications to allow this negotiation to take

place.

This document proposes the fragment-oriented solution for the real-

time encapsulation format part of the architecture. The general

approach is to start from the PPP Multilink fragmentation protocol

[2] and provide a small number of extensions to add functionality and

reduce the overhead.

1. Introduction

As an extension to the "best-effort" services the Internet is well-

known for, additional types of services ("integrated services") that

support the transport of real-time multimedia information are being

developed for, and deployed in the Internet.

The present document defines the fragment-oriented solution for the

real-time encapsulation format part of the architecture, i.e. for the

queues-of-fragments type sender [1]. As described in more detail in

the architecture document, a real-time encapsulation format is

required as, e.g., a 1500 byte packet on a 28.8 kbit/s modem link

makes this link unavailable for the transmission of real-time

information for about 400 ms. This adds a worst-case delay that

causes real-time applications to operate with round-trip delays on

the order of at least a second -- unacceptable for real-time

conversation. The PPP extensions defined in this document allow a

sender to fragment the packets of various priorities into multiple

classes of fragments, allowing high-priority pac...