Dual VLAN tag translation

You can use the dual VLAN tag translation (also known as dual VLAN tag rewrite) feature to deploy switches in service-provider domains, allowing dual-tagged, single-tagged, and untagged VLAN packets to come into or exit from the switch. Operations added for dual VLAN tag translation are swap-push, swap-swap, and pop-push. Dual VLAN tag translation supports: 

• Configuration of S-VLANs (NNI) and C-VLANs (UNI) on the same physical interface
• Control protocols such as VSTP, OSPF, and LACP 
• IGMP snooping 
• Configuration of a private VLAN (PVLAN) and VLAN on a single-tagged interface 
• Use of TPID 0x8100 on both inner and outer VLAN tags