The value of this object represents the maximum bi-directional
bandwidth which can be allocated by a gatekeeper for call
connections from one zone to other zones.
When no value has been assigned to a particular
cgkLZoneInterzoneBandwidth entry i.e. its value is -1, the value
of this object is used for the maximum bi-directional bandwidth
of the call connections between that zone and other zones.
Value must be less than or equal to the value specified in
cgkMIBDefaultTotalBandwith.
A value of -1 indicates no bandwidth limitation has been set.