The connection oriented
networking protocols, like
ATM, network connection setup protocols (UNI/NNI
Signaling) assume that end points of a connection are fixed terminals. This makes it difficult to use such protocols transparently under wireless environments (read
WATM).
In order to trace and find a mobile terminal position,
we need additional addressing schemes and protocols along with some modifications to the connection setup process. Such a scheme is known as the Location Management.
There are no set standards yet for the WATM Location Management and therefore a lot of different ways are suggested. One of the more accepted schemes has following approach:
- Each MT (mobile terminal) has a 'Home Base Station' statically bound with it. On bootup, the MT registers with its Home Base Station.
- The Home Base Station maintains a Forwarding Table for each MT registered with it. It maintains the address of the MT and its current location.
- Everytime an MT hands off, it updates this Forwarding table.
- Every future request to reach the moved MT is made to its Home Base Station, which forewards this request based on the entries in the Forwarding Table.