Browse Prior Art Database

ISO-TP0 bridge between TCP and X.25 (RFC1086)

IP.com Disclosure Number: IPCOM000001895D
Original Publication Date: 1988-Dec-01
Included in the Prior Art Database: 2000-Sep-12
Document File: 7 page(s) / 18K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

J.P. Onions: AUTHOR [+2]

Abstract

This memo specifies a protocol that is used to bridge ISO TP0 packets between X.25 and TCP networks. This technique is useful when interconnecting a DDN IP internet to an X.25 subnetwork. This is not a "magic bullet" solution to the DDN/ISO interoperability problem. Rather, if one is running higher-layer ISO protocols in both networks (namely ISO TP0), then a TP0 bridge can be used to achieve connectivity.

This text was extracted from a ASCII document.
This is the abbreviated version, containing approximately 15% of the total text.

Network Working Group J. Onions

Request for Comments: 1086 Nottingham

M. Rose

TWG

December 1988

ISO-TP0 bridge between TCP and X.25

Status of this Memo

This memo proposes a standard for the Internet community. Hosts on

the Internet that choose to implement ISO TP0 transport connectivity

between TCP and X.25 based hosts are expected to experiment with this

proposal. TCP port 146 is reserved for this proposal. Distribution

of this memo is unlimited and comments are highly encouraged.

Introduction

This memo specifies a protocol that is used to bridge ISO TP0 packets

between X.25 and TCP networks. This technique is useful when

interconnecting a DDN IP internet to an X.25 subnetwork. This is not

a "magic bullet" solution to the DDN/ISO interoperability problem.

Rather, if one is running higher-layer ISO protocols in both networks

(namely ISO TP0), then a TP0 bridge can be used to achieve

connectivity.

The protocol itself is fairly simple as the method of operation for

running TP0 over the TCP and X.25 protocols have previously been

defined. A bridge offering ISO-TP0 gateway services simply applies

both methods as appropriate. The protocol works by TP0/TCP hosts

"registering" an X.25 subaddress (and corresponding TCP port/IP

address) with the bridge. TP0/X.25 hosts use the standard method for

establishing, maintaining, and releasing connections. When a

connection is established, the bridge establishes the corresponding

TCP connection and simply shuffles TP0 packets between the two. When

a TP0/TCP host initiates a connection, it establishes a TCP

connection to the bridge using port number 146 and communicates the

desired X.25 address. The bridge establishes a connection to the

native X.25 host and simply shuffles TP0 packets between the two.

1. Introduction and Motivation

The migratory protocol described in [RFC1006] makes possible the

transmission of TP0 packets between hosts on TCP/IP internets. With

the addition of a small protocol converter, a TCP/IP host can be made

to appear in the X.25 addressing space and be able to accept and make

connections using the TP0 protocol.

This procedure is particularly useful in the following cases:

1. A host on an IP based internet can communicate with hosts on

X.25 based networks providing the hosts are running ISO protocols.

...