Protocol; Contents; Introduction; Operation - Nortel Circuit Card Installation Manual

Appendix A: LAPB Data Link Control

protocol

Contents

Introduction

Operation

This section contains information on the following topics:
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Frame structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LAPB balanced class of procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Commands and responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Description of procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
This chapter describes the LAPB Data Link Control protocol used with the
QPC513 ESDI card. The protocol is a subset of the HDLC procedures which
are described in International Organization for Standardization procedures
ISO 3309-1979 (E), ISO 4335-1979 (E) and appendices 1 and 2, and ISO
6256-1981 (E). Refer to these procedures for complete LAPB details.
Applications which use an ESDI port in synchronous mode must conform to
the following requirements.
Circuit Switch Equipment transfers data to the QPC513 in blocks consisting
of 1 to 128 eight-bit octets. Each block is processed in accordance with the
Circuit Card Description and Installation
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