As we saw the basic of EVC in my earlier post EVC: Ethernet Virtual Circuits – Part 1 & here we will dig some more to know about EVC.
1] What is Ethernet Flow point (EPF)? : - EPF is a Service Instance which classifies frames
belongs to particular Ethernet service & also defines & applies feature,behavior & forwarding action.
2] Ethernet Virtual Circuit (EVC): - EVC is management plane containers which represents
globally & also do 1-toMany mapping for EVC to EPF.
3] Bridge Domain (BD): - BD is a broadcast domain local to that device.
EVC Bridge Domain: EVC bridges decouple VLAN from broadcast domain.
- VLAN are treated as encapsulation on a wire.
- VLAN on a wire are mapped to internal bridge domain.
- Result : Per – Port VLAN Significance.
Flexible Service Mapping
- Service Instance construct Layer 2 Flow on Ethernet Interface
- Single Tagged
- Double Tagged
- Header / Payload
Encap do1q 100 : match any frame with Outer Tag equal to 100
Encap dot1q 100 sec 200 : match any frame with outer tag as 100 and second tag as 200
Encap Default : Service Instance with default encapsulation matches all frame otherwise unmatched by any other S-I on the same port.
Advance Frame Manipulation or VLAN Tag Manipulation
- PUSH Operation : Add one VLAN Tag or Two VLAN Tag
- POP Operation : Remove One VLAN Tag or Two VLAN Tag
- Translation Operation :
1:2 VLAN Translation
2:1 VLAN Translation
2:2 VLAN Translation
The Biggest advantage on EVC is to support multiple services per physical port . That means you can have multiple service under one physical port.
- Local Connect
- EoMPLS ( xconnect)
- L2 Multipoint Bridge
- L2 Multipoint Bridge ( VPLS , SVI-Based EoMPLS)
- L2 Point to multipoint bridge
- L3 Termination