What type of cable (e.g. RJ48 ? specific pinouts ? crossover or rolled ?) would be used for a test environment to connect one Cisco router Serial port to another Cisco router serial port in order to simulate a WAN connection (e.g. MPLS, T1, etc...) ? Can a regular RJ 48 T1 cable - the one that is used to connect the Cisco router serial port to the wall at the CPE - be used for that ?