S/UNI®-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
Figure 16 Termination of F4 Segment and End-to-End Point Connection
Connection End-Point (End-to-End Point)
Segment End-Point
VCC-AIS-Ete (Connection within a defined segment)
VCC-AIS-Seg (Connection within a defined segment)
VCC1
VCC2
VCC-AIS-EtE (Connection not within a defined segment)
VCC3
VCC-AIS-EtE
VCC-RDI-Seg
F4 (VPC)
VCC-RDI-EtE
VCC4
VCC5
VCC-RDI-Seg
VCC-RDI-EtE
VPC-AIS-Seg
VPC-RDI-Seg
In Figure 16 above, a VPC flow is being terminated. The VPC flow is both a segment end-point,
and a connection (end-to-end) point. In the S/UNI-ATLAS-3200 search table, both the segment
and end-to-end connections would resolve to a single F4 OAM connection. Five VCCs are being
switched out from the VPC connection (all five VCCs would be setup as separate connections).
In this scenario, a segment VPC-AIS cell is received on the VPC connection. A segment VPC-
RDI cell would be generated (if the AUTO_RDI bit is logic 1 in the VC Table) and sent to the
Backwards Cell Interface. The segment VPC-RDI cell would carry the segment Defect Location
and segment Defect Type information. The response of the switched VCCs is as follows:
VCC1 belongs to a segment flow, therefore, a both a segment and an end-to-end VCC-AIS cell
are generated within 0.5 seconds of noticing that the VPC connection is in segment AIS alarm.
VCC1 will continue to generate segment and ETE VCC-AIS cells at a rate of one per second
(nominally) while the VPC connection is in AIS alarm (i.e the AIS_segment alarm bit is asserted
for the VPC connection).
VCC2 does not belong to a segment flow, therefore, an end-to-end VCC-AIS cell is generated
within 0.5 seconds of noticing that the VPC connection is in segment AIS alarm. VCC2 will
continue to generate end-to-end VCC-AIS cells at a rate of one per second (nominally) while the
VPC connection is in AIS alarm (i.e. the AIS_segment alarm bit is asserted for the VPC
connection).
VCC3 is a segment end-point, therefore a segment VCC-RDI assuming the AUTO_RDI bit is
logic 1 in the VC Table) and an end-to-end VCC-AIS cell are generated for this connection within
0.5 seconds of noticing that the VPC connection is in segment AIS alarm. VCC3 will continue to
generate segment VCC-RDI and end-to-end VCC AIS cells at a rate of one per second
(nominally) while the VPC connection is in segment AIS alarm (i.e. the AIS_segment_alarm bit is
asserted for the VPC connection).
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
111
PMC [ PMC-SIERRA, INC ]
