Which two statements are correct regarding LDP-signaled VPLS instances? (Choose two.)
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A. B. C. D.BD
LDP-signaled VPLS (Virtual Private LAN Service) instances are used to extend a Layer 2 broadcast domain over an IP/MPLS network. These instances use the Label Distribution Protocol (LDP) to signal the VPLS pseudowires between Provider Edge (PE) routers.
The correct statements regarding LDP-signaled VPLS instances are:
A. You must enable the Layer 2 VPN signaling NLRI. This statement is true. In order to signal Layer 2 VPNs using LDP, you need to enable the Layer 2 VPN signaling Network Layer Reachability Information (NLRI). This NLRI is used by LDP to advertise VPLS-related information to its peers.
B. You must configure the same VPLS identifier on all peers. This statement is also true. The VPLS identifier is a 32-bit value used to identify a VPLS instance. All PE routers in the VPLS instance must be configured with the same VPLS identifier, which is used to associate the VPLS pseudowires with the correct VPLS instance.
C. You must define a the same site-identifier value on all peers. This statement is incorrect. Site-identifier is an optional parameter that can be used to provide additional separation between VPLS instances. It is not required to be the same on all peers, and it can be configured independently on each PE router.
D. You must define all neighbors using their tunnel end-point IP addresses. This statement is also incorrect. In an LDP-signaled VPLS instance, the PE routers use LDP to discover and establish pseudowire connections with each other. They do not need to be configured with explicit neighbor information, and the tunnel end-point IP addresses are not required to be used for this purpose.
In summary, the correct statements regarding LDP-signaled VPLS instances are that the Layer 2 VPN signaling NLRI must be enabled, and the same VPLS identifier must be configured on all peers.