Android Question SIP Server on Tablet

[aaronk]

Hello,

Just wondering if the following can be done or not..

I have 3 tablets:
Tablet 1 - Master, Tablet that will need to somehow have some type of SIP server installed
Tablet 2 - Slave, can only talk to Tablet 1
Tablet 3 - Slave, can only talk to Tablet 1

I need to somehow have a SIP server on Tablet 1 running and using VoIP Tablet 2 & Tablet 3 can only talk to tablet 1.

If tablet 2 was to call tablet 3 it needs to not allow the call.

Does anyone know how you can create a VoIP Sip server on a tablet (Android Device) and allow the other ones to connect to it?

I don't want to run any external servers and only want to use the 3 Android devices.