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Cisco ONS 15310-CL, ONS 15310-MA, and ONS 15310-MA SDH Ethernet Card Software Feature and Configuration Guide, R9.1 and R9.2
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Chapter 17 CE-Series Ethernet Cards
CE-MR-6 Ethernet Card
Table 17-8 shows which values are mapped to the priority queue for sample IP ToS settings.
(ToS settings span the full 0 to 255 range, but only selected settings are shown in Table 17-8.)
For a CoS-tagged frame, the CE-MR-6 can map the eight priorities specified in CoS to priority or best
effort. The user can configure a different CoS in CTC at the card-level view under the Provisioning >
Ether Ports tabs. Any CoS class higher than the class specified in CTC is mapped to the priority queue,
which is the queue geared towards low latency. By default, the CoS is set to 7, which is the highest CoS
value. This results in all traffic being treated with equal priority by default.
Table 17-9 shows values that are mapped to the priority queue for CoS settings.
Ethernet frames without VLAN tagging use ToS-based priority queueing if both ToS and CoS priority
queueing is active on the card. The CE-MR-6 card’s ToS setting must be lower than 255 (default) and
the CoS setting lower than 7 (default) for CoS and ToS priority queueing to be active. A ToS setting of
255 (default) disables ToS priority queueing, so in this case the CoS setting would be used.
Ethernet frames with VLAN tagging use CoS-based priority queueing if both ToS and CoS are active on
the card. The ToS setting is ignored. CoS based priority queueing is disabled if the CoS setting is
7 (default), so in this case the ToS setting would be used.
If the CE-MR-6 card’s ToS setting is 255 (default) and the CoS setting is 7 (default), priority queueing
is not active on the card, and data gets sent to the default normal traffic queue. If data is not tagged with
a ToS value or a CoS value before it enters the CE-MR-6 card, it also gets sent to the default normal
traffic queue.
Table 17-8 IP ToS Priority Queue Mappings
ToS Setting in CTC ToS Values Sent to Priority Queue
255 (default) None
250 251–255
150 151–255
100 101–255
50 51–255
0 1–255
Table 17-9 CoS Priority Queue Mappings
CoS Setting in CTC CoS Values Sent to Priority Queue
7 (default) None
67
56, 7
4 5, 6, 7
3 4, 5, 6, 7
2 3, 4, 5, 6, 7
1 2, 3, 4, 5, 6, 7
0 1, 2, 3, 4, 5, 6, 7