Browse Prior Art Database

PPP Magnalink Variable Resource Compression (RFC1975)

IP.com Disclosure Number: IPCOM000004194D
Original Publication Date: 1996-Aug-01
Included in the Prior Art Database: 2000-Sep-13
Document File: 5 page(s) / 8K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

D. Schremp: AUTHOR [+3]

Abstract

The Point-to-Point Protocol (PPP) [1] provides a standard method of encapsulating multiple protocol datagrams over point-to-point links. The PPP Compression Control Protocol [2] provides a method for negotiating data compression over PPP links.

This text was extracted from a ASCII Text document.
This is the abbreviated version, containing approximately 38% of the total text.

Network Working Group D. Schremp

Request for Comments: 1975 J. Black

Category: Informational J. Weiss

Magnalink

August 1996

PPP Magnalink Variable Resource Compression

Status of This Memo

This memo provides information for the Internet community. This memo

does not specify an Internet standard of any kind. Distribution of

this memo is unlimited.

Abstract

The Point-to-Point Protocol (PPP) [1] provides a standard method of

encapsulating multiple protocol datagrams over point-to-point links.

The PPP Compression Control Protocol [2] provides a method for

negotiating data compression over PPP links.

The Magnalink Variable Resource Compression Algorithm (MVRCA) allows

a wide range of interoperable compression implementations whose

performance characteristics are a function of available CPU and

memory resources.

Introduction

The Magnalink variable resource compression algorithm defines a

family of interoperable compression solutions with compression

performance as a function of available CPU and memory resources. It

addresses the need for an algorithm which can be tailored to the

system on which it is implemented without compromising

interoperability.

Licensing

Source licenses are available on a non-discriminatory basis.

The contact person for evaluation under NDA and Licensing is:

Director of OEM Sales

Magnalink Communications Division

Telco Systems Inc.

63 Nahatan Street

Norwood, Mass. 02062

Phone: (617) 255-9400, Fax: (617) 255-5885

oem@magna.telco.com

MVRCA Packets

Before any MVRCA packets may be communicated, PPP must reach the

Network-Layer Protocol phase[1], and the Compression Control Protocol

must reach the Opened state.

The text of a Packet to be compressed begins with PPP Protocol

number. The Packet header including the PPP Protocol number may have

already been compressed when Protocol-Field-Compression has been

negotiated.

Reliability and Sequencing

MVRCA packets may be sent across an unreliable link or may use a

reliable link as described in "PPP Reliable Transmission"[3] if the

reliable link has been negotiated. If frames are delivered out of

order or a frame is dropped, the decompressor will detect this and

requests a resynchronization using the Reset-Req and Reset-Ack types

of the CCP[2], with the compressor for the affected context.

Data Expansion

Although the compression algorithm may occasionally expand a data

packet, there is no expansion in MVRCA since any expanded data is

instead sent uncompressed. Dictionary synchronization is maintained

across uncompressed packets.

Encapsulation

The encapsulation consists of the PPP Protocol Identifier, a bit to

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