H3C Technologies H3C SR8800 - Manual (Page 30)

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Unicast transmission
Figure 4 Unicast transmission on an RPR ring
Figure 4 shows how a unicast data frame is transmitted on an RPR ringlet:
1. The source station inserts the unicast frame into the data stream on Ringlet 0 or Ringlet 1.
2. Transit stations transit the frame.
3. The frame is copied and stripped when it reaches the destination station or when its time to live (TTL)
expires.
Different from traditional ring technologies where unicast frames are removed from the ring at the source
station, RPR adopts destination stripping to remove unicast frames from the ring at the destination station.
This increases bandwidth utilization and spatial bandwidth reuse efficiency.
Broadcast, multicast, and unknown unicast transmission
Figure 5 Broadcast, multicast, and unknown unicast transmission on an RPR ring
Figure 5 shows how a broadcast, multicast, or unknown unicast frame is transmitted on an RPR ringlet:
1. The source station inserts the frame into the data stream on Ringlet 0 or Ringlet 1.
2. Transit and destination stations copy and transit the frame if the TTL of the frame has not expired.
3. The frame is stripped when it returns to the source station or when its TTL expires.
Insert to
ringlet 0
Copy from
ringlet 0
Copy from
ringlet 0
Copy from
ringlet 0
Copy from
ringlet 0
Strip