Juniper MX Series

Summary

MC-LAG is a simple but yet effective feature that can be used to increase the performance and resiliency in your network. You’re able to choose between an active-active or active-standby topology that best fits your use case. For example, when creating full mesh topology of IEEE 802.1Q links between different tiers of a network, it would make sense to use an active-active topology to fully utilize each of the links and also provide resiliency during a failure scenario.

ICCP is the heart and soul of MC-LAG; it leverages existing and well-understood technologies such as TCP/IP and BFD, which make the configuration and troubleshooting very easy for new users. ICCP serves as a very simple and extendable protocol that keeps track of state changes, configuration changes, and signal information between routers.

One of the most common use cases for MC-LAG is to dual-home CE devices. This comes in the form of top-of-rack switches or providing node redundancy for customer routers in a WAN environment. The benefits of MC-LAG are:

• No spanning tree is required; MC-LAG has built-in features in the PFE to detect and prevent Layer 2 loops.

• The CE implementation is transparent and only requires IEEE 802.3ad.

• The PE implementation of MC-LAG doesn’t require a reboot and is less disruptive to the network.

• The design of MC-LAG allows each PE to operate independently from the other. In the event of a misconfiguration of a PE, the error would be isolated to that particular PE router and not impact the ...