Clear-Com HX System Frames - Manual (Page 92)

Loss of single fiber connection
If a single fiber connection is lost on one ring and the other ring is intact then the active ring
always attempts to heal itself by reversing the direction of data flow to bypass the failed
connection. The self healing mechanism is performed autonomously by the fiber linking card.
If the extent of the failure is such that the active ring is unable to heal itself the system will
switch to the secondary ring. Switching to the secondary ring will cause audio breaks or
disturbances and temporary loss of crosspoint data.
The self healing mechanism and the switchover between redundant cards and rings is
performed automatically by the matrix frame.
Loss of a single node
If a node is lost on one ring due to a single fiber-optic linking card set failure and the fiber-
optic linking card set for the other ring is healthy and the other ring is intact then the active
ring always attempts to heal itself.
The nodes adjacent to the failed node will loop-back their connections to the failed node
healing the ring using the working remains of the ring.
If the extent of the failure is such that the active ring is unable to heal itself the system will
switch to the secondary ring. Switching to the secondary ring will cause some minor
degradation in audio, but this is not usually detectable unless a scope is used.
The self healing mechanism and the switchover between redundant cards and rings is
performed automatically by the matrix frame.
If a single node is lost on both rings due to multiple fiber-optic linking card set failures etc the
nodes adjacent to the failed node(s) will loop-back their connections to the failed node(s)
healing the rings and the most intact ring will be used. The configuration software will report
the failure.
Loss of two fiber connections
If two adjacent fiber connections are lost on the ring this will be handled as for the loss of a
single node where the nodes adjacent to the failed node will loop-back their connections to
the failed node healing the ring.
The configuration software will report the failure correctly as two failed cables. If two non-
adjacent fiber connections are lost on the ring the nodes adjacent to the failures will loop-
back their connections to the failed cables healing the ring into 2 separate smaller rings. The
configuration software will report the failure.
Note:
In this instance the two sub-rings will be dependent on their Ethernet connections for
configuration and data transmission but there will be no audio path between them.
Switching to the secondary ring will cause some minor degradation in audio, but this is not
usually detectable unless a scope is used. The self healing mechanism and the switchover
between redundant cards and rings is performed automatically by the matrix frame.
If two adjacent fiber connections are lost on one ring and the other ring has a similar
failure this will be handled as for the loss of a single node where the nodes adjacent to the
failed node will loop-back their connections to the failed node healing the ring.
92 Eclipse HX-Median User Guide