Hi Need some help regarding length of cable connecting CISCO Router(E1 card)with 61c. What is the save length of cable connecting CISCO router with 61c. Note that we are using 61c rls 4.5/Dual to connect with it a remote site by using CISCO router E1 option.Both side have CISCO router with E1 card and these router are connected with nortel PBX.I wants to know the maximum length of cable which can be use between CISCO router and Nortel PBX at both sites.