The Cisco LRE 48 POTS Splitter, is a set of filters that is used in installations where the PBX system is on-site and LRE traffic shares the same telephone lines as existing voice, integrated services digital network (ISDN), or Smart Phone services. The Splitter separates the LRE traffic from the other phone services, sending the high-frequency LRE traffic to a Catalyst 2900 LRE XL switch and the low-frequency telephone services to a private branch exchange (PBX) switch