Dear friend!
PWE3 is a Layer 2 service bearer technology that emulates the basic behaviors and characteristics of services such as ATM/IMA, Ethernet, and TDM on a packet switched network (PSN).Aided by the PWE3 technology, conventional networks can be connected by a PSN. Therefore, resource sharing and network scaling can be achieved.
As shown in figure, the PE device uses CESoPSN to emulate native TDM services. SAToP uses a similar encapsulation process, but does not identify the E1 frame format or process the timeslots of the E1 frame.

More: TDM PWE3
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