What multicast address do Auto-RP Mapping Agents use to advertise their selected RP?

Auto-RP (Automatic Rendezvous Point) is a Cisco proprietary protocol used in multicast routing to automate the discovery of Rendezvous Points (RPs) in a Multicast environment. The correct multicast address used by Auto-RP Mapping Agents to advertise their selected RP information is 224.0.1.39.

This specific multicast address is part of the well-known range, reserved for specific multicast applications, and is used by Auto-RP Mapping Agents to send out messages that include details about the RPs they manage, allowing multicast sources and receivers to find the correct RP for their multicast traffic.

Using the correct multicast address ensures that all routers that are configured to listen for Auto-RP messages can receive and process the RP information. This helps maintain the efficiency and reliability of multicast communication within the network.

In contrast, other addresses listed serve different purposes: 224.0.0.1 is used for all systems on the local subnet, 224.0.1.40 is not associated with Auto-RP, and 239.255.255.250 is used for SSDP (Simple Service Discovery Protocol), which is unrelated to the functions of Auto-RP. Each of these addresses has specific uses in multicast data transmission, making them