The list of disconnect cause codes that the H.323
subsystem has received. A disconnect can originate
either from the far-end gateway or from the opposite
call leg on the local gateway. Whenever a disconnect
occurs the entry in the table will be updated by the
agent. The cause for disconnect is mapped to one of
cause codes and if an entry for the cause code exists
in the table, number of disconnects is incremented for
that entry, otherwise a new entry is made with cause
code as index.