hi dilip,
for 1 DRI or 1 BBX, it requires 2 timeslot of 1E1. so normally if your site has 3 sector with 1+1+1 configuration then you require 7TS(2+2+2+1)…last 1 timeslot is for signalling….
T1 and E1 difference is of standard and Bandwith. E1 is eurpoe standard while T1 is american standar. E1 is 2 MBPS while T1 is 1.25 mbps…
hope it will solve your query…