S/UNI®-ATLAS-3200 Telecom Standard Product Data Sheet
Preliminary
When an AIS or RDI cell is generated due to CC_AIS_RDI, per-PHY RDI,
Send_RDI/AIS_End_to_end, or Send_RDI/AIS_Segment, the AIS/RDI will contain the defect
type programmed into the OAM Configuration field of the VC table, and the local defect location
programmed in the Defect Location register.
When an AIS or RDI is generated due to reception of an AIS cell, the generated cell will contain
the AIS Defect Location and AIS Defect Type fields which are stored in the VC Table of the
connection which received the AIS. For instance, an F5 Ete RDI generated as the result of
receiving an F4 Segment AIS would use the segment defect location and type stored for the F4
connection.
If an F4 connection enters the AIS alarm condition (segment or end-to-end), the associated F5
connections will not declare AIS themselves (i.e. the AIS_end_to_end alarm and/or the
AIS_segment alarm bit will not be asserted on the F5 connection). The F5 connections will,
however, most likely be in the CC_alarm condition (both segment and end-to-end), because any
cell that would clear the CC alarm in the F5 connections would also clear AIS alarm in the F4.
10.11 F5 to F4 OAM Processing
The S/UNI-ATLAS-3200 also supports the aggregation of F5 connections into F4 connections.
The VCs must be set up in much the same way, with one VC for each VCC, and another VC for
the F4 OAM connection. However, the OAM connection will not be an end point, and the only
OAM functions performed by the F4 are the sourcing of end-to-end and segment CC cells. The
F4 OAM connection must still have a valid search onto which cells with VCI = 3 or VCI=4
terminate, as Loopback, RDI, and Bwd PM cells from the BCIF must search correctly onto the
connection (if Search_From_BCIF is logic 1).
The F4 Continuity Check process in the aggregated F4 is aware of OAM and other cells
generated on the component F5 flows, and correctly counts them as user cells.
F4 Forward PM flows may be generated by associating many F5 connections with a single F4
Forward PM session. This PM connection will treat all F5 cells (other than, optionally, RM cells)
as F4 user cells and will include them in the generated PM counts.
10.12 Constraints on F5 and F4 VC Table Record Addresses
The VC Table Record address is a 16 bit number identifying an F5 or F4 flow. This number
corresponds to a data structure in the internal DRAM.
Each VC Table record is stored in one of the 4 banks in the internal DRAM. The bank in which a
record is stored is identified by the least significant two bits of the VC record. Thus each record
is stored in either bank 0 (VCRA[15:0] = xxxxxxxxxxxxxx00), bank 1
(VCRA = xxxxxxxxxxxxxx01), bank 2 (VCRA[15:0] = xxxxxxxxxxxxxx10) or bank 3
(VCRA = xxxxxxxxxxxxxx11).
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990553, Issue 4
116
PMC [ PMC-SIERRA, INC ]
