EVC means different things in different fields.

EVC, Ethernet Virtual Connection, is very similar to the concept of PVC/SVC in ATM technology.

EVC describes an end-to-end concept. We can think of it as a logical pipe. Once an Ethernet frame enters the pipe, it will not be leaked unless it comes out from another opening of the pipe.

EVC can be more formally described as: "an instance associated with two or more UNIs".

EVC plays a very important role in carrier-grade Ethernet services. By constructing statistically multiplexed logical pipes within limited network resources, traffic can be effectively isolated. By applying corresponding restrictions on the logical pipes and the traffic in them,

Control, carrier-class Ethernet has relatively complete flow control capabilities, which is an important feature of becoming a carrier-class business.