: XCVR 2450 requirement for Network Protocols

Hi,
I want to compare and test few network protocols using USRP1. I have two
USRP1 and two XCVR-2450 daughter-boards. Can any one tell me that if I
want to transmit and receive simultaneously from a USRP, like in case of
Automatic Repeat Request (ARQ) for data and ACK/NACK, how many XCVR-2450
daughter-boards and associated antenna do I require? Waiting reply and
thanking you in anticipation.

-Ahmed