| Description | This table contains configuration and state information of
point-to-point and point-to-multipoint interface
cross-connects.
Each entry in the table models two bi-directional interfaces on
opposite sides of a bi-directional cross-connect.
For a point-to-point cross-connect, there can be up to four
entries in the table with the same value of coifccCcIndex, due
to the presence of protection interfaces.
All four entries are associated with each other due to
APS configuration (for now, this would be done through
the CISCO-APS-MIB). If both sides A and B are configured
for 1+1 APS protection, and a cross-connect between
interfaces A and B is created, then the following
cross-connect entries will be present:
The cross-connect with coifccCcKind value 'provisioned' is the
one that is created through cross-connect configuration and the
cross-connects with coifccCcKind value 'protection' are those
that are created automatically due to APS configuration.
Low interface High interface coifccCcKind
A B provisioned
A B' protection
A' B protection
A' B' protection
When the cross-connect between A and B is deleted, all four
cross-connect entries will disappear.
Each side of the point-to-point cross-connect can have up to
two interfaces, for example when SONET 1+1 Automatic
Protection Switching (APS) is used. Any one of the four
entries of a point-to-point cross-connect can be created,
and the remaining three entries will be created
automatically. However only the 'provisioned' entry can be
explicitly deleted, which also causes the corresponding
'protection' entries to be deleted. Note that use of the
word 'protection' is different from its usage in SONET 1+1 APS.
In particular, there is no requirement that the 'provisioned'
cross-connect must be between the SONET 'working' interfaces.
A point-to-multipoint connection consists of one root and
many leaves. Copies of the traffic received at the root
interface are transmitted out each of the leaf interfaces.
For a point-to-multipoint cross-connect with N leafs,
the manager creates N 'provisioned' entries in this table.
Where N is determined by the manager based on some application.
In the presence of APS configuration, the same
point-to-multipoint (N leafs) cross-connect, in addition
to having N 'provisioned' entries in this table, can have upto
an additional 3N 'protection' entries automatically configured.
The terms low and high are chosen to represent numerical
ordering of the two interfaces associated with a cross-connect.
That is, the interface with the lower value of ifIndex is
termed 'low', while the other interface associated with the
cross-connect is termed 'high'. This terminology is used to
provide directional information; for example, the
coifccCcL2HOperStatus applies to the low->high direction, and
coifccCcH2LOperStatus applies to the high->low direction. |