Alcatel-Lucent 9500 MXC, User Manual, Page: 172 / 916

Chapter 3. 9500 MXC Nodes
Vol. II-3-78 Alcatel-Lucent
Refer to:
• Super PDH Rings on page 3-78
• Super PDH Ring Operation on page 3-79
• 1+1 Protected Ring Links on page 3-84
• Co-channel XPIC Operation on a Ring on page 3-86
• Ethernet Traffic on a Ring on page 3-87
For information on maximum ring capacities, refer to Appendix E.
Super PDH Rings
9500 MXC Node supports protected PDH ring configurations for capacities to
75xE1 or 100xDS1, with traffic switching at the INU/INUe level. The rings are
implemented by east/west facing RAC and ODU combinations from a single
node (INU/INUe). A closed loop is formed when each node is connected to two
adjacent nodes, the east and west nodes.
North Gateway or Any-to-Any Ring Topologies are supported.
Within the protected ring there are two traffic rings, one nominated as clockwise,
the other anti-clockwise. Under normal no-fault conditions, all traffic is passed
on the clockwise
primary ring.
In the event of a fault the secondary , anti-clockwise ring, provides the protection
capacity needed. Traffic is looped onto the secondary ring at one side of the break
point, and off at the other side, to bypass the break. This process is called
wrapping .
One or more radio paths can be replaced by a fiber span using the DAC 155oM.
Hot-standby or diversity protection for ring links is scheduled, which has
particular application on long and difficult paths (paths subject to fading), using
diversity options.
East, west, clockwise and anti-clockwise descriptors are conventions used to
describe and configure 9500 MXC ring operation. The physical implementation of
a ring may be quite different.
Ring protection protects the payload and alarm I/O addressing between nodes;
ring protection does not protect auxiliary data.