Appendix A: LAPB Data Link Control protocol Page 905 of 906Circuit Card Description and InstallationDescription of procedureThe basic LAPB procedures must be implemented to satisfy the following:• standard use of the poll/final bit (for more information, seeISO-4375-1979-[E])• exception condition reporting and recovery implemented in accordancewith BX.25 and ADCCP specifications• link set-up and disconnect implemented according to BX.25specificationsTable 281Commands and responsesCommand Response OptionI 8RR RRRNR RNRREJ REJ or FRMR 2SABM UADISC DMLegend:I: InformationRR: Receive readyRNR: Receive not readyREJ: RejectSABM: Set asynchronous balanced modeDISC: DisconnectRSET: ResetFRMR: Frame rejectUA: Unnumbered acknowledgeDM: Disconnect modeOption 2: Provides ability for more timely reporting of I frame sequence errorsOption 8: Limits the procedure to allow I frames to be commands only
