Juniper Networks® Field Guide and Reference

Multicast Scoping

Multicast scoping is a technique that can be used to limit multicast traffic by configuring it to an administratively defined topological region. Major objectives of scoping are to relieve stress on scarce resources, such as bandwidth, and to improve privacy or scaling properties. IP multicast implementations can achieve some level of scoping by using the time-to-live (TTL) field in the IP header. However, TTL scoping has proven difficult to implement reliably, and the resulting schemes often are complex and difficult to understand.

Administratively scoped IP multicast provides clearer and simpler semantics for multicast scoping. The key properties of administratively scoped IP multicast are that packets addressed to administratively ...