Based on MPLS and Ethernet technologies, VPLS is an L2VPN technology that is used to implement point-to-multipoint VPN networking. VPLS is better than both the earlier point-to-point L2VPN services and Layer 3 virtual private network (L3VPN) services requiring carriers to manage the routing information.
VPLS forwards data according to MAC entries. In most cases, MAC address learning is automatically performed among devices. To protect services against attacks and faults, VPLS provides an additional set of MAC control mechanisms.
During fault rectification in a link protection scenario, if service VSI PWs go Up before protocol VSI PWs, service VSI loops occur. To prevent this issue, you can configure an L2VPN monitoring group to monitor the VSI recovery status and delay the unlocking of service VSI PWs.
This section describes how to configure static bidirectional forwarding detection (BFD) to detect the connectivity of a virtual private LAN service (VPLS) single-segment pseudo wire (SS-PW).
Multicast fast switch can fast switch VSI multicast traffic from a faulty primary TE tunnel to a backup tunnel. Multicast fast switch can be enabled in VPLS over TE scenarios in which the public network tunnels of a VSI are TE tunnels and the VSI forwards multicast traffic.
BGP AD VPLS-enabled devices exchange extended BGP packets to automatically discover member VSIs in a VPLS domain and then use LDP FEC 129 to negotiate PW establishment to achieve automatic VPLS PW deployment.
In VPLS networking in which a CE is multi-homed to multiple PEs, configuring VPLS multi-homing prevents routing loops between the multi-homed CE and its connected PEs.
This section describes how to configure OAM mapping. When an intermediary such as a switch exists between a PE and a CE, you can configure OAM mapping to associate the OAM status on an AC interface with the PW status.
When a VPLS recurses to a public network, to minimize the impact of VPLS service changes on the convergence of other services, configure the public-network-and-private-network decoupling function for VPLS.