The MIB module contains ATM Trunk statistics. TERMINOLOGY ----------- PVC: Permanent Virtual Circuit OAM: Operation and Management CRC: Cyclic redundancy check AIS: Alarm Indication Signal TDM: Time Division Multiplex FERF: Far End Receive Failure CPS: Common Part Sub-layer PDU: Protocol Data Unit HEC: Header Error Control DSP: Digital Signal Processing CID: Channel Identifier UUI: User-to-User Information VoIP: Voice over IP CCS: Common Channel Signaling VoAAL2: Voice over AAL2 SDU: Service Data Unit HDLC: High Level Data Link Control SAR: Segmantation and Reassembly External AIS - is an Alarm Indication Signal associated with a maintenance alarm detected on a defective maintenance span, that is transmitted in the direction of the defect as a substitute for normal signal. The purpose is to show the downstream entities that a defect has been identified and to prevent other maintenance alarms consequent to this first defect. External AIS bit stream is represented by an all 1's signal. Ref - ITU-T Rec. M.20 sec. 5.4.2 a External RAI - is a Remote Alarm Indication signal that is transmitted upstream from an entity that has detected defects persisting long enough to constitute a received signal failure. Its purpose is to report in the backward direction that there is an interruption of service in the forward direction. The forward direction is from the originating end of the alarm to the remote end. The backward direction is from the remote end to the orginating end of the alarm. Ref - ITU-T Rec. G.704 section I.366.2 - ANNEX N External Connection AIS - is a Alarm Indicating Signal transmitted in the downstream direction from the AAL type 2 connecting point that first detects a defect affecting the AAL type 2 connection; this includes defects indicated by lower layers. Ref - ITU-T Rec. I.610 sec External Connection RDI - is a signal transmitted upstream by an AAl type 2 endpoint that is in an alarm state as the result of having received an AAL type2 connection AIS or having detected a defect that affects the AAL type2 connection. All ATM alarm definitions are specified in I.610 (ITU standard).

MIB content (95 objects)


Cisco Systems, Inc.
Contact info
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2005-08-10 00:00
Add new objects - catsPvcOamLpbkTimeoutCnts - catsPvcNewOamLpbkTimeoutDur - catsPvcActiveOamLpbkTimeoutDur - catsPvcOamLpbkTimeoutThreshold
2004-05-12 00:00
Initial version of the MIB.