M7i, M10i, and M40e routers with 4–port Channelized OC3/STM1 Circuit Emulation (CE) PICs support TDM interfaces using the Structure-Agnostic Time Division Multiplexing (TDM) over Packet (SAToP) protocol [RFC 4553] encapsulation, and support T1/E1 and SONET clocking features. The Channelized OC3/STM1 PIC was designed specifically for mobile backhaul applications.