This object is used to represent a domain name under which
the Media Gateway could also be registered in a DNS name
server.
The value of this object reflects the value of
cmgwConfigDomainName from the entry with a value of
'gateway(1)' for object cmgwConfigDomainNameEntity of
cMediaGwDomainNameConfigTable.
If there is no entry in cMediaGwDomainNameConfigTable with
'gateway(1)' of cmgwConfigDomainNameEntity, then
the value of this object will be empty string.