MPLS L2 VPN - Any to Any Interworking

The L2 VPN Interworking feature supports Ethernet, 802.1Q(VLAN), Frame Relay, ATM AAL5, and PPP attachment circuits over MPLS.

The L2 VPN Interworking function is implemented in two modes.


Bridged Interworking Mode

In bridged interworking mode, Ethernet frames are extracted from the AC and sent over the pseudo wire. AC frames that are not Ethernet are dropped. In the case of a VLAN, the VLAN tag is removed, leaving an untagged Ethernet frame. This interworking functionality is implemented by configuring the interworking ethernet command under the pseudo-wire class configuration mode.


Roted Interworking Mode

In routed interworking, IP packets are extracted from the AC and sent over the pseudo wire. AC frames are dropped if they do not contain the IPv4 packets. This interworking functionality is implemented by configuring the interworking ip command under the pseudo-wire class configuration mode.


Configuring Layer 2 VPN Interworking

Ethernet to VLAN Interworking

CE1:
interface ethernet0/0
  ip address 172.16.10.1 255.255.255.252


PE1:(Loopback 10.10.10.101/32)
pseudowire-class Eth-VLAN
  encapsulation mpls
  interworking ethernet
!
interface fastethernet5/0
  no ip address
  xconnect 10.10.10.102 100 encapsulation mpls pw-class Eth-VLAN


PE2:(Loopback 10.10.10.102/32)
pseudowire-class VLAN-Eth
  encapsulation mpls
  interworking ethernet
!
interface fastethernet5/0
!
interface fastethernet5/0.100
  no ip address
  encapsulation dot1q 100
  xconnect 10.10.10.102 100 encapsulation mpls pw-class VLAN-Eth


CE2:
interface ethernet0/0
!
interface ethernet0/0.100
  encapsulation dot1q 100
  ip address 172.16.10.2 255.255.255.252


Frame Relay to AAL5 Interworking

CE1:
interface atm6/0.100
  pvc 1/100
    encapsulation aal5snap
    ip address 172.16.1.1 255.255.255.252


PE1:
pseudowire-class AAL5-FR
  encapsulation mpls
  interworking ip
!
interface atm6/0.100 point-to-point
  pvc 1/100 l2transport
    encapsulation aal5snap
    xconnect 10.10.10.102 100 pw-class AAL5-FR


PE2:
pseudowire-class FR-AAL5
  encapsulation mpls
  interworking ip
!
frame-relay switching
!
interface serial0/0
  no ip address
  encapsulation frame-relay
  clock source internal
  frame-relay intf-type dce
  connect FR s0/0 100 l2transport
    xconnect 10.10.10.101 100 pw-class FR-AAL5


CE2:
interface ethernet0/0.100
  encapsulation dot1q 100
  ip address 172.16.1.2 255.255.255.252



Frame Relay to PPP Interworking

CE1:
interface S0/0
  encapsulation frame-relay
  ip address 172.16.1.1 255.255.255.252


PE1:
pseudowire-class FR-PPP
  encapsulation mpls
  interworking ip
!
interface serial1/0
  no ip address
  encapsulation frame-relay
  frame-relay intf-type dce
!
connect FR serial1/0 100 l2transport
  xconnect 10.10.10.101 100 pw-class FR-PPP


PE2:
pseudowire-class PPP-FR
  encapsulation mpls
  interworking ip
!
interface serial1/0
  encapsulation ppp
  xconnect 10.10.10.102 100 pw-class PPP-FR


CE2:
interface s1/0
    encapsulation ppp
    ip address 172.16.1.2 255.255.255.252


Frame Relay to VLAN Interworking

CE1:
interface serial0/0.100 point-to-point
  ip address 172.16.1.1 255.255.255.252
  frame-relay interface-dlci 100


PE1:
frame-relay switching
!
pseudowire-class FR-PPP
  encapsulation mpls
  interworking ip
!
interface serial2/1
  no ip address
  encapsulation frame-relay
  frame-relay intf-type dce
!
connect FR serial2/1 100 l2transport
  xconnect 10.10.10.102 100 pw-class FR-PPP


PE2:
pseudowire-class VLAN-FR
  encapsulation mpls
  interworking ip
!
interface fastethernet5/0.100
  encapsulation dot1q 100
  xconnect 10.10.10.101 100 encapsulation mpls pw-class VLAN-FR


CE2:
interface fastethernet0/0.100
  encapsulation dot1q 100
  ip address 172.16.1.2 255.255.255.252


AAL5 to VLAN Interworking

CE1:
interface atm1/0.100 point-to-point
  mtu 1500
  ip address 172.16.1.1 255.255.255.252
  pvc 1/100
    encapsulation aal5snap


PE1:
pseudowire-class AAL5-VLAN
  encapsulation mpls
  interworking ethernet
!
interface atm3/0.100 point-to-point
  mtu 1500
  pvc 1/100 l2transport
    encapsulation aal5snap
    xconnect 10.10.10.102 100 encapsulation mpls pw-class AAL5-VLAN


PE2:
pseudowire-class VLAN-AAL5
  encapsulation mpls
  interworking ethernet
!
interface fastethernet0/0.100
  encapsulation dot1q 100
    xconnect 10.10.10.101 100 encapsulation mpls pw-class VLAN-AAL5


CE2:
interface fastethernet0/0.100
  encapsulation dot1q 100
  ip address 172.16.1.2 255.255.255.252

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