I have my own ewsd switch and gr-303

I have a siemens ewsd switch, it supports gr303 links. What i want to do is have one asterisk server connected to the switch(gr-303) passing calls and data over ethernet to my router. Then use asterisk servers at customer locations to handle voice and data either over a data t1 or voice and data t1. Can asterisk be used as a concentrator? If so how is best used? Using data t1s and everything go into the asterisk server as voip and get passed to gr303 then to the switch, or channelizing a t1 using some for data some for voice into the asterisk back out the gr303? So i guess i would eat up one port t1 for each side for each customer?