Logical Link Number And Name; Time Slots, Characteristics, And Logical Attributes; Creating, Changing, And Deleting Logical Links - Paradyne COMSPHERE 6800 Series Multiplexer Management And Configuration Manual

For example, if a network includes DACS nodes, you can define alternate routes when a link
between two DACS nodes, or between an ACCULINK and a DACS node, fails. With node/link
routing and logical links, you can define an alternate path by assigning a logical link of the
appropriate number of time slots to the alternate path. The logical link is then included in the
node's routing table, allowing automatic routing to route the failed channel groups over the path.
Or, a second fixed route could be defined using the logical link.
Logical links may also be defined between two nodes connected directly to each other. In that case,
their usefulness is limited to simply restricting the bandwidth available to each channel group.
The 6800 Series NMS allows you to change, add, display and delete logical links. You can also
make/break logical link connections. Logical links are configured by specifying the following
information using the Change Logical Link (chll) and the Create Logical Link (crll) commands.

Logical Link Number and Name

Logical links must have unique numbers (0 to 9999) at each node and the logical link number must
be the same for the two nodes at each end of the same logical link. The NMS provides the
capability for you to assign a network-wide unique name to each logical link. Logical link numbers
can be up to 6 characters including the mandatory prefix LL. Logical link names can be up to 18
characters including the mandatory prefix ll-.

Time Slots, Characteristics, and Logical Attributes

You assign a capacity to a logical link by entering the time slots to be used for it. The number of
time slots determines the link's capacity.
Once a logical link is configured, it must be placed in the connected state in order to allocate the
bandwidth to the logical link.
A logical link can have associated with it physical or logical attributes. Attributes are
characteristics of physical and logical links. Physical attributes are those that are associated with
physical (T1) links. Logical attributes are those associated with logical links. Logical links inherit
physical attributes from their associated physical links.
As part of each logical link configuration, a configuration state of active or inactive may be
specified for each of the corresponding logical attributes. For each logical link, the Clear Channel
attribute will be configured as active if the line encoding for the physical link is B8ZS or the
specified logical link time slots are configured for ACAMI. Otherwise, the Clear Channel attribute
is automatically set as inactive.

Creating, Changing, and Deleting Logical Links

When a logical link is created using the Create Logical Link (crll) command, the NMS stores the
information about it in a database table, and also sends the create request to the appropriate nodes.
The NMS then keeps this table in synch with the nodal information by verifying its database
whenever a logical link command (change, delete, or display) is executed, then updating the
database appropriately.
6800-A2-GB21-10
Logical Link Number and Name
Node Endpoints
Time slots, Characteristics, and Logical Attributes
August 1994
Managing Multiplexers
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