Multiple Instances for LDP and Carrier-of-Carriers VPNs
By configuring multiple LDP routing instances, you can use LDP to advertise labels in a carrier-of-carriers VPN from a core provider PE router to a customer carrier CE router. Having LDP advertise labels in this manner is especially useful when the carrier customer is a basic ISP and wants to restrict full Internet routes to its PE routers. By using LDP instead of BGP, the carrier customer shields its other internal routers from the Internet at large. Multiple-instance LDP is also useful when a carrier customer wants to provide Layer 3 VPN or Layer 2 VPN services to its customers.
For an example of how to configure multiple LDP routing instances for carrier-of-carriers VPNs, see the Junos Feature Guide on the product documentation page of the Juniper Networks website, located at https://www.juniper.net/.
