EVC

Hi, link discuss the process/operation of EVC and I just want to clarify few things.

https://supportforums.cisco.com/t5/network-infrastructure-documents/understanding-ethernet-virtual-circuits-evc/tac-p/3406382#M5476

The "Order of operation" mention that, For example we already categorize the received frame the next action will be "pop" and forward the un-tagged from to BDI.

What if we are using EFP as Trunk.

interface GigabitEthernet0/1/2 (Pointing to Customer/Partner)

service instance trunk 1 ethernet

encapsulation dot1q 30-40

rewrite ingress tag pop 1 symmetric

bridge-domain from-encapsulation (Derives BDI from encapsulation)

When V30 frame(Ingress) comes, it will be categorize and mapped to SI1 then will "POP" the first tagged which is V30 and forward to BDI 30 or 40.

Q:

1. Now my question is since we pop the first frame how can we know what outer tag will be used(30-40) and how can ASR know which BDI will the untagged frame will be forwarded since already untagged?

2. What is the equivalent config of these IOS command to XR?

   in IOS

---VLAN CREATION

vlan 1

name test

vlan 2

name  test2

---Access port

interface FastEthernet0/3/2

switchport access vlan 1

---TRUNK MODE

interface FastEthernet0/3/1

switchport mode trunk

switchport trunk allowed vlan add vlan1, vlan2, vlan3

Thank you