Description of procedure – Nortel Networks 1000 User Manual

Page 1012

1012

LAPB Data Link Control protocol

Table 423
Commands and responses (cont’d.)

Command

Response

Option

RNR

REJ

REJ or FRMR

SABM

DISC

Legend:
I: Information
RR: Receive ready
RNR: Receive not ready
REJ: Reject
SABM: Set asynchronous balanced mode
DISC: Disconnect
RSET: Reset
FRMR: Frame reject
UA: Unnumbered acknowledge
DM: Disconnect mode
Option 2: Provides ability for more timely reporting of I frame sequence errors
Option 8: Limits the procedure to allow I frames to be commands only

Description of procedure

The basic LAPB procedures must be implemented to satisfy the following:

•

standard use of the poll/final bit (for more information, see
ISO-4375-1979-[E])

•

exception condition reporting and recovery implemented in accordance
with BX.25 and ADCCP specifications

•

link set-up and disconnect implemented according to BX.25
specifications

Nortel Communication Server 1000

Circuit Card Reference

NN43001-311

02.06

Standard

27 August 2008