Alcatel-Lucent 9500 MXC User Manual page 173

North Gateway or Any-to-Any Ring Topologies
Super PDH Ring Operation
Ring Protection Operation
3DB 23063 ADAA - Rev 004 July 2007
Super-PDH ring architecture supports configurations for North Gateway or
Any-To-Any topologies. With North Gateway, one of the nodes operates as the
gateway, through which all traffic on the ring is sourced and sent. For any-to-any
operation, traffic can be routed from any node in the ring to any other node. In
both modes, the E1 or DS1 circuits involved are unique on the ring (cannot be
re-used within the ring).
Most ring topologies use a single gateway where all circuits are sourced and
sunk. For such rings 64xE1 or 84xDS1 is the nominal ring maximum because of
backplane capacity limitations at the gateway, but where a ring incorporates a
number of gateways, up to 75xE1 or 100xDS1 can be ring-protected. For
information on ring capacity maximums, refer to Appendix E.
This section addresses:
• Ring Protection Operation on page 3-79
• Ring Delay Times on page 3-81
• Double Break Operation on page 3-82
• Point-to-Point Traffic Overlay on a Ring on page 3-83
• Ring-Node Intersection on page 3-83
• Fiber Ring Closing on page 3-84
For Ethernet traffic applications, refer to Ethernet Traffic on a Ring on page 3-87
Figure 3-47 represents normal, no-fault operation for a super-PDH ring. It shows
two circuits in a 64xE1 ring routed clockwise around the primary ring. Data sent
to the ring on an E1 interface exits after travelling around the ring.
The secondary ring circuits are not being used, and carry pseudo-random data.
9500 MXC User Manual
Vol. II-3-79