Topology And Protection Control Frame Formats - Cisco ONS 15454 SDH Configuration Manual

Chapter 26 Configuring IEEE 802.17b Resilient Packet Ring
Figure 26-3
(TP) frames are usually sent to the broadcast address.
Figure 26-3
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Figure 26-4
only the nearest neighbor depending on whether it is a single-choke fairness frame (SCFF) or
multi-choke fairness frame (MCFF). Fairness frames are included in the total bandwidth of the QoS A0
service class. This eliminates the need for a destination address (DA). The MCFF type also includes an
additional frequency division duplexing (FDD) frame to help smooth the fairness variation. The field SA
Compact is the address of the station providing the fair rate.
The ML-Series card supports multi-choke fairness frames from other stations on the RPR-IEEE. The
Note
ML-Series card does not generate these frames.
illustrates the RPR-IEEE topology and protection control frame. Topology and protection

Topology and Protection Control Frame Formats

TTL to Dest
Base Control
MAC da
MAC sa
TTL Base
Extended Control
hec
Control Type
Control Version
Control Data Unit
FCS
illustrates the RPR-IEEE fairness frame. Fairness frames are sent either to all stations or
Cisco ONS 15454 and Cisco ONS 15454 SDH Ethernet Card Software Feature and Configuration Guide, R8.0
Header
Payload
Trailer
RPR-IEEE Framing Process
26-5