TDM CESoPSN Overview
Circuit Emulation Service over Packet-Switched Network (CESoPSN) is an encapsulation layer intended to carry NxDS0 services over a packet-switched network (PSN). CESoPSN enables pseudowire emulation of some properties of structure-aware time division multiplexed (TDM) networks.
Particularly, CESoPSN enables the deployment of bandwidth-saving fractional point-to-point E1 or T1 applications as follows:
A pair of customer edge (CE) devices operate as though they were connected by an emulated E1 or T1 circuit, which reacts to the alarm indication signal (AIS) and remote alarm indication (RAI) states of the devices’ local attachment circuits.
The PSN carries only an NxDS0 service, where N is the number of actually used time slots in the circuit connecting the pair of CE devices, thus saving bandwidth.