pxb4340e Infineon Technologies Corporation, pxb4340e Datasheet - Page 40

• Manufacturer Part Number: pxb4340e
• Description: Atm Oam Processor Aop
• Manufacturer: Infineon Technologies Corporation

The first BR cell is generated when the first FM cell for this PM flow has been received. This BR
cell carries valid data to initialize the BR data collection point, but no valid data for data
collection. Only the following BR cells contain valid data for data collection.
The PM function is split into three different parts:
• PM generation
• PM analysis and loop
• PM data collection.
PM generation includes
• Calculation of total user cell count for all cells and for high priority cells (CLP=0)
• Calculation of a BIP-16 checksum over user cell payload
• Generation of FM cells containing the calculated results.
The FM cells are coded as F4 or F5 automatically for VPCs and VCCs, respectively, end-end or
segment as specified. FM cell sequence number and CRC-10 checksum are also generated.
The blocksize can be selected between 2 and 65536. The optional time stamp of the FM cell is
not generated.
Forced OAM cell insertion is used for both up- and downstream FM cell insertion. During
insertion of FM cells the user cell stream is stored in the respective buffers (see
).
PM analysis and loop include
• Calculation of total user cell count for all cells and for high priority cells (CLP=0)
• Extraction of FM cells
• Appending of calculation results to the end of the cell
• Conversion of the cell into a BR cell
• Re-insertion of the BR cell in opposite direction.
PM analysis uses the same PM processor circuits as the generation process. In total 128 PM
processor circuits are shared by up- and downstream direction.
For PM data collection 128 circuits are provided, which are independent of the PM processor
circuits. Both PM and data collection processors have their respective entries in the internal PM/
data collection RAMs.
The assignment of PM and data collection processors to connections in up- or downstream
direction is arbitrary. VPCs and VCCs can be assigned by programming pointers in the F4 and
F5 entries, respectively (see
page 121, and
page 123).
A typical PM scenario is shown in
in case of VP end-to-end monitoring. Two nodes
are involved, Node ’a’ where the VPC
is created and Node ’b’ where VPC
is terminated. In
a-b
a-b
backward direction the associated VPC
is created in Node ’b’ and terminated in Node ’a’.
b-a
Creation of a VPC allways occurs at an outgoing port of a node and termination at an incoming
port. Hence the Originating End Point (OEP) of VPC
is located in the downstream part of the
a-b
PXB 4340 AOP in Node a, and the Terminating End Point (TEP) of VPC
is located in the
a-b
upstream part of the PXB 4340 AOP in Node b. For VPC
the situation is mirrored according
b-a
to
.
Data Sheet
2-40
04.2000