Two modes of circuit emulation are supported: unstructured and structured. Unstructured mode is supported for DS1 and E1 channels per RFC 4553, Structure-Agnostic Time Division Multiplexing (TDM) over Packet (SAToP). Structured mode is supported for N*64 kb/s circuits as per RFC 5086, Structure-Aware Time Division Multiplexed (TDM) Circuit Emulation Service over Packet Switched Network (CESoPSN). Also, DS1, E1, and N*64 kb/s circuits are supported (per MEF8). TDM circuits are optionally encapsulated in MPLS or Ethernet as per the referenced standards in the following examples.
The following figure shows an example of RFC 4553 (SAToP) MPLS PSN encapsulation.
The following figure shows an example of CESoPSN packet format for an MPLS PSN.
The following figure shows an example of MEF8 PSN encapsulation.
