GNS3 Topology: Any Transport over MPLS in VLAN Mode

Any Transport over MPLS (AToM) transports data link layer (Layer 2) packets over a Multiprotocol Label Switching (MPLS) backbone. AToM encapsulates Layer 2 frames at the ingress PE and sends them to a corresponding PE at the other end of a pseudowire, which is a connection between the two PE routers. The egress PE removes the encapsulation and sends out the Layer 2 frame.

AToM supports the following like-to-like transport types:
• ATM Adaptation Layer Type-5 (AAL5) over MPLS
• ATM Cell Relay over MPLS
• Ethernet over MPLS (VLAN and port modes)
• Frame Relay over MPLS
• PPP over MPLS
• High-Level Data Link Control (HDLC) over MPLS


BENEFITS of AToM

The AToM product set accommodates many types of Layer 2 packets, including Ethernet and Frame
Relay, across multiple Cisco router platforms, such as the Cisco 7200 and 7500 series routers. This
enables the service provider to transport all types of traffic over the backbone and accommodate all
types of customers.

Upgrading to AToM is transparent to the customer. Because the service provider network is separate from the customer network, the service provider can upgrade to AToM without disruption of service to the customer. The customers assume that they are using a traditional Layer 2 backbone.


PART 1 (Ethernet over MPLS VLAN Based Configuration)



PART 2 (EoMPLS Preferred Path using IP routing)



PART 3 (EoMPLS Preferred Path using MPLS TE and path protection using FRR)

AToM can use MPLS traffic engineering (TE) tunnels with fast reroute (FRR) support. AToM VCs can
be rerouted around a failed link or node at the same time as MPLS and IP prefixes.




http://fengnet.com/book/layer%202%20vpn%20architectures/ch09.html
http://www.cisco.com/en/US/docs/ios/mpls/configuration/guide/12_4t/mp_12_4t_book.html

GNS3 Topology: Layer 3 VPNs Over Multipoint L2TPv3 Tunnels

VPN services have been traditionally deployed over IP core networks by configuring MPLS or through L2TPv3 tunnels using point-to-point links. This feature introduces the capability to deploy layer 3 VPN services by configuring multipoint L2TPv3 tunnels over an existing IP core network. This feature is configured on only the PE routers and requires no configuration on the core routers. The L2TPv3 multipoint tunnel network allows layer 3 VPN services to be carried through the core without the configuration of MPLS. 

Border Gateway Protocol (BGP) is used to advertise the tunnel endpoints and the subaddress family indentifier (SAFI) specific attributes (which contains the tunnel type, and tunnel capabilities). This feature introduces the tunnel SAFI and the BGP SAFI-Specific Attribute (SSA) attribute. The tunnel SAFI defines the tunnel endpoint and carries the endpoint IPv4 address and next hop. The tunnel SAFI is identified by the SAFI number 64. The BGP SSA carries the BGP preference and BGP flags. It also carries the tunnel cookie, tunnel cookie length, and session ID. The BGP SSA is identified by attribute number 19. 

These attributes allow BGP to distribute tunnel encapsulation information between PE routers. VPNv4 traffic is routed through these tunnels. The next hop, advertised in BGP VPNv4 updates, determines which tunnel to use for routing tunnel traffic.

(2008,MPLS VPN over L2TPv3 Tunnels, retrieved from http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/cs_l3vpn.html, February 2011)



PART 1



PART 2



you can find this topology here

GNS3 Topology: LAN Protocols over L2TPv3

PART 1 (port to port manual method)



PART 2 (port to port manual session with keepalives)