PXB4340E Datasheet, PDF (133/185 Pages) Infineon Technologies AG – ICs for Communications

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In this example a VPC containing a VCC is terminated. A number of PM measurements are
performed:
• end-to-end PM at F4 (VPC) level bi-directional
• segment PM termination and creation of a new segment at F5 (VCC) level uni-directional
In total 4 PM processors and 2 data collection processors are involved. Their associated RAM
entries are shown in )LJXUH . The two connections involved, VPCa and VCCb are
represented by 2 entries in each up- and downstream RAM, a F4 and a F5 entry with the F5
entry pointing to the F4 entry. Each entry has 4 pointer + enable pairs to define:
• the origination point of a PM flow
• the endpoint of a PM flow
• a data collection point for a end-to-end flow
• a data collection point for a segment flow.
For origination and termination points the selection between end-to-end and segment flows is
done in the PM main RAM by setting the flow type (FT) bits. At termination points the generation
of BR cells can be enabled by setting BRDIS=0. A further parameter to specify is the block length
BL. In the example of )LJXUH  two different block sizes are used, 1024 (coding 1001) at the
F4 level and 256 (coding 0111) at the F5 level.
The data collection function evaluates the contents of BR cells. It can be enabled at any point
along the path of the BR cells, including the analyzing point where the BR cells are generated.
In the present example the evaluation occurs at the end point of the BR cells.
The scenario shown in )LJXUH  can only occur at an ingress port of a switch, where VPCs are
terminated. Hence the origination of a end-to-end F4 flow should not be programmed in
upstream direction. Conversely in downstream direction a F4 end-to-end flow must not be
enabled.
Data Sheet
4-133
04.2000