Hi
Telcos provide Ethernet over SDH connectivity from his Mux . The connectivity output from your telco would be a ethernet , so you can use your Gig ports on your 7200 or your 7600 routers. You can also get a OC-3 output,then you need to use stm-1 cards ,PA-POS , if your telco supports .
If you require multiple localtion connectivity , then you can bring it via your switch and do dot1q encapsulation on your Routers.
Hope this helps
regards
vanesh k