Dear Suresh,
e1t1 cards used for the dedicated e1, means take from krown or fiu, in this u not instrol any microwave, not requeid any frequency etc, but in rri card u have to instrol m/w , in this u have to gave power , frequency etc.
in e1t1 4 interface & in rri 2 interface ,in rri u have to take upto 16 e1 in side then bypass it,