The value of tmnxSubAuthPlcyUserNameAppend specifies what will be
appended to the user-name sent to the RADIUS server.
When the value is 'nothing', the user-name will be created as
indicated by tmnxSubAuthPlcyUserNameFormat.
When the value is 'domainName', the user-name will be created as
indicated by tmnxSubAuthPlcyUserNameFormat, appended by '@' and a
domain-name if returned via a lookup in the local-user-database
(TIMETRA-LOCAL-USER-DB-MIB::tmnxLocUsrDbDhcpDomainName).
From release 8.0R4 onwards, use 'tmnxSubAuthPlcyUserNameOp' instead;
the value of this object is ignored if the value of
'tmnxSubAuthPlcyUserNameOp' is different from 'noOperation'.