This is an entry in the 'cwtLinkInfoTable'. Each
entry corresponds to one link in the network.
a) The entries in this table are derived from PNNI
PTSE database or added by a network management
station.
b) The entries in the PNNI PTSE database
time out when no new PTSE is received from a node
after a certain time. However, the corresponding
entries are not removed from this table.
c) Only the network management station can delete
an entry from this table.
d) A network management station cannot modify an
existing entry in this table.