 | Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |
Previous versions of JUNOS software support multiple VPN routing and forwarding (VRF) instances of Border Gateway Protocol (BGP), Intermediate System-to-Intermediate System (IS-IS), Open Shortest Path First (OSPF), Protocol Independent Multicast (PIM), and Routing Information Protocol (RIP). JUNOS Release 5.4 and later adds support for multiple instances of the Label Distribution Protocol (LDP).
This support allows LDP to be used to advertise labels in a carrier-of-carriers scenario from a core provider edge (PE) router to a customer carrier edge (CE) router. This is especially useful when the carrier customer is a basic Internet service provider (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 2 VPN or Layer 3 VPN services to its customers.
Using multiple-instance LDP lets you circumvent one of the requirements of RFC 3107: the need to run full-mesh internal BGP (IBGP) within the carrier customer’s autonomous system (AS). When you use multiple-instance LDP, full-mesh IBGP is unnecessary.
This feature guide covers these topics:
| Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice. | |