mellowd CCIE blog A CCIE blog.
Posts with the tag lv3pn:

MPLS L3VPN- Route Distinguisher vs Route Target vs VPN Label

A lot of people confuse the above 3 items. I’ll explain exactly what each of the 3 above items do, how you can see them, and how the routers use them to provide a L3VPN service. Let’s take the following topology for this post: Here we have 2 L3VPN customers running over our MPLS core. R5 is advertising R8 is also advertising Route Distinguisher The route distinguisher’s sole job is to keep a route unique while the PE routers advertise NLRI (Network Layer Reachability Information) to each other. If R5 and R8 both advertise to R3, how will R3 advertise both of those routes to R4 while keeping them unique.