DLCI address space is limited to 10 bits.
This creates a possible 1024 DLCI addresses. The usable portion of
these addresses are determined by the LMI type used. The Cisco LMI
type supports a range of DLCI addresses from DLCI 16-1007 for carrying
user-data. The ANSI/ITU LMI type supports the range of addresses from
DLCI 16-992 for carrying user-data. The remaining DLCI addresses are
reserved for vendor implementation. This includes LMI messages and
multicast addresses. In the Figure, assume two PVCs, one between Atlanta and
Los Angeles, and one between San Jose and Pittsburgh. Los Angeles uses
DLCI 22 to refer to its PVC with Atlanta, whereas Atlanta refers to
the same PVC as DLCI 82. Similarly, San Jose uses DLCI 22 to refer to
its PVC with Pittsburgh and Pittsburgh uses DLCI 62. The network uses internal mechanisms to keep
the two locally significant PVC identifiers distinct.
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