Which two Layer 2 VPN methods support interworking between customer sites with different Layer
2 encapsulation at each end (for example, Frame Relay to Ethernet interworking)? (Choose two.)

A.
AToM

B.
VPLS

C.
GET VPN

D.
L2TPv3

Explanation:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t2/feature/guide/gtl2tpv3.html#wp1040784
The Layer 2 Tunnel Protocol Version 3 feature expands on Cisco support of the Layer 2 Tunnel
ProtocolVersion 3 (L2TPv3). L2TPv3 is an Internet Engineering Task Force (IETF) l2tpext working

group draft thatprovides several enhancements to L2TP for the capability to tunnel any Layer 2
payload over L2TP.
Specifically, L2TPv3 defines the L2TP protocol for tunneling Layer 2 payloads over an IP core
network usingLayer 2 virtual private networks (VPNs). Benefits of this feature include the following:
•L2TPv3 simplifies deployment of VPNs
•L2TPv3 does not require Multiprotocol Label Switching
•L2TPv3 supports Layer 2 tunneling over IP for any payload
http://www.cisco.com/en/US/products/ps6646/products_ios_protocol_option_home.html
Cisco Any Transport over MPLS (AToM) is a solution for transporting Layer 2 packets over an
MPLSbackbone. It enables Service Providers to supply connectivity between customer sites with
existing data linklayer (Layer 2) networks via a single, integrated, packet-based network
infrastructure: a Cisco MPLS network.Without separate networks that each have network
management environments, Service Providers can deliverLayer 2 connections over an MPLS
backbone.
Cisco AToM provides a common framework to encapsulate and transport supported Layer 2 traffic
types overan MPLS network core. Service Providers can use a single MPLS network infrastructure
to offer connectivityfor supported Layer 2 traffic and for IP traffic in Layer 3 VPNs.