X.25

Orion
Consultancy

Understanding X.25

Overview

Although more recent innovations may attract attention, X.25 still delivers formidable price/performance. The principles of packet-switching and the X.25 recommendations are explained in this two day technical course. The associated X series standards are examined and the course provides a detailed analysis of the structure and operation of networks built to these recommendations. This course is invaluable for those involved in wide-area network design, management and support.

Potential delegates

This course is valuable for all those involved in the evaluation, design and implementation of an X.25 based packet network.

Prerequisites

Attendance of Orion’s Introduction to Data Communications course or equivalent practical experience.

Duration

1 day

Course Objectives

By the end of the course delegates will be able to:

	Define and describe the benefits of packet switching
	Describe the operation of an X.25 based packet network
	Describe in detail the full X.25 suit of protocols

Course Content

Introduction

History; PSTN; Packet switching; The placement of X.25 now and in the future, PAD, DTE & DCE;

Standards

ITU-T; X.2; X.3; X.28; X.29; X.30; X.31; X.75; X.121

Link Access

X.21 physical layer; alternate interfaces; link access

Frame Formats;

frame formats; frame transparency; address/control/info fields; FCS; LABP; sequence numbers; error detection and recovery processes

The Packet Layer and Facilities

Packet format; PTI; packet management; facilities markers and classes; flow control negotiation; user groups; reverse charging; fast select