| Description | If the value of this object is 'bidirectional(0)', then
the LSR supports the use of a given DLCI as a label for
both directions independently. If the value of
this object is 'unidirectional(1)', then the LSR
uses the given DLCI as a label in only one direction.
This is the EXACT value for the Frame Relay Session
Parameter, field D (for VC Directionality). The
Frame Relay Session Parameter is an optional
parameter in the Initialization Message.
The description from rfc3036.txt is:
'D, VC Directionality
A value of 0 specifies bidirectional VC capability,
meaning the LSR can support the use of a given
DLCI as a label for both link directions
independently. A value of 1 specifies
unidirectional VC capability, meaning a given
DLCI may appear in a label mapping for one
direction on the link only. When either or both
of the peers specifies unidirectional VC
capability, both LSRs use unidirectional VC
label assignment for the link as follows. The
LSRs compare their LDP Identifiers as unsigned
integers. The LSR with the larger LDP
Identifier may assign only odd-numbered DLCIs
in the range as labels. The system with the
smaller LDP Identifier may assign only
even-numbered DLCIs in the range as labels.'
Please refer to the following reference for a
complete description of this feature. |