Cisco MGX 8850 PXM45 Release Notes page 34

Limitations, Restrictions, and Notes
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Caution For narrowband service modules cards, whenever T1 or T3 cards are replaced with E1 or E3 cards, or
vice versa, the clrsmcnf command for that slot must be used.
Reserved VCIs
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FRSM-12-T3E3
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Release Notes for Cisco MGX 8850 (PXM45), MGX 8850 (PXM1E), and MGX 8830, Software Release 3.0.10
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No bandwidth CACing support on the narrow band service modules, except for the
MGX-RPM-PR-256/512 which is checked against the OC-3 card rate. Bandwidth CACing is
supported on PXM1E uplink port.
The maximum bandwidth to be distributed among narrow band service modules is ~OC10 while
traffic on the network interfaces can achieve true OC12 line rate.
Traffic should be balanced between the cell bus controllers to achieve the OC-10 rate. The traffic
should be distributed equally at a rate of about OC-5 on the two cell bus controllers. The cell bus
controllers cannot load share to achieve OC-10 with one Cell Bus set at an OC-6 rate, and another
cell bus set at an OC-4 rate. Anything above OC-6 will be dropped. However, if only one cell bus
controller is used and the other cell bus controller is not used, then it can achieve OC-10. On an
8850, the CBCs are split between the left and right side of the chassis: CBC0 supports slots 1 to 6
and 17 to 22, and CBC1 supports slots 9 to 14 and 25 to 30. On an MGX 8830, CBC0 supports slots
3, 5, 10, and 12, and CBC1 supports slots 4, 6, 11, and 13.
The PXM1E with a UI-S3 card will drop up to 70 percent of outgoing Ethernet packets to specific
switches. Use an approved Cisco hub/switch. This only applies to packets sent on the UI-S3 Ethernet
interface. Known incompatible hubs are HP8000ProCurve and Netgear FS108.
The following are the reserved VCIs that the customer cannot provision:
vpi=0, vci=5 is used for SSCOP for UNI signaling ports (UNI, none ports do not need
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signaling). If it is a virtual terminal or EVUNI, then the minimum vpi and the VCI=5 are used
for SSCOP.
vpi=0, vci=18 is used for PNNI RCC (if the port is not NNI, or Virtual NNI, then you do not
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need this).
– vpi=0, vci=16 is used for ILMI if ILMI is enabled. Similarly, for virtual terminal or EVUNI, it
is minimum vpi and vci=16.
– If MPLS is configured it is vci=33 in the similar fashion as above.
– If NCDP is configured it is minimum VPI and vci=34 for NCDP clocking.
The FRSM-12-T3E3 card does not have the capability of supporting E3 signals.
CLLM will not be supported: The FRSM-12-T3E3 card can support connection level congestion
through ATM EFCI. It also supports FR-ATM interworking of ECN and EFCI. Frame level
congestion only happens in the rare case of full line rate sub 15-byte frames; therefore, the hardware
will only support Port Level Congestion Management in the Frame Relay domain.
BERT: Not supported.
Sub-rate DS3: Not supported.
The following are port and connection limitations pertaining to the new FRSM-12-T3E3 card:
– 4 bytes header length with Stratcom LMI is not supported.
– LMI on Frame Forwarding port is not supported.
OL-2914-01 Rev D0, July 3, 2003