[ns] Questions about Mobile-IP

[Diepchi T Tran <Diepchi.T.Tran@lerc.nasa.gov>]

Hi ns-users,
I want to simulate a wired-cum-wireless network including Mobile-IP and
have the following problems:

1) I simulated a network having one mobile node, a HA node and two FA
nodes. First, I put two FA nodes far apart and get the interim periods
between the HA-FA1 and FA1-FA2. Second, I put 2 FA nodes close to each
other such that I can eliminate the interim period while mobile node moving
between the FAs. There is no interim period between the FA nodes. But the
throughput of this simulation is lower compared to the throughput of the
simulation in which the FA nodes is far apart. The reason is the interim
period between HA-FA1 in the second simulation is longer than that in the
first simulation. 
Does ns support hand-off option or is there any other way to simulate the
handoff?.

2) Approximately, how big is the domain of a base-station in diameter?. Can
I use "radius" like for mobile node to define the base-station's domain?.
In my first simulation, the domain of the FA1 is just about half of the
domain of the HA.

3)Can a mobile node be a wireless node at some times and be a wired node at
the other time?. If yes, what should I put in the script?. In my
simulation, the mobile node is an airplane. It is a wired node at the gate
and wireless node when it flies. 

Please help.

Thank you very much,
Cindy
Diepchi Tran 
Phone (216) 433-8861
Fax   (216) 433-8705