If juniAtm1483ProfileSubscriberNamePrefix has the value 'enabled', the
value of this object serves as the prefix of a full subscriber name.
The full name is constructed by appending local geographic information
(slot, port, etc.) that uniquely distinguishes the subscriber.
This parameter is valid only when juniAtm1483ProfileSubscriberEncaps is
configured to one of the following values:
ip(0),
bridgedEthernet(19)
For all other values of juniAtm1483ProfileSubscriberEncaps it returns an
empty string.