How Multicast Routes in the Same Segment Choose the DR

D.

In a multicast network using Protocol Independent Multicast (PIM), a designated router (DR) is elected to manage multicast traffic for a particular subnet or segment. The DR is responsible for forwarding multicast traffic from sources to receivers on that segment.

The process of DR election in a PIM network involves sending hello messages between routers to determine the DR for each subnet. The hello messages contain information such as the router's priority, address, and holdtime.

Option A is incorrect because anycast RP (rendezvous point) is not related to DR election. Anycast RP is a technique used in multicast networks to provide redundancy and load balancing by using multiple RP addresses that share the same IP address.

Option B is also incorrect because even though the Nexus switches do not have the concept of DR, DR election is still performed by other devices in the multicast network.

Option C is correct. PIM hello messages are sent to the multicast address 224.0.0.13, which is the PIM router discovery address. Each router on the segment sends a hello message with its priority, and the router with the lowest priority is elected as the DR for that segment.

Option D is incorrect because the router with the highest priority is not selected as the DR in PIM. The priority value is used to break ties between routers with the same IP address.

In summary, multicast routes in the same segment choose the DR through PIM hello messages sent to the multicast address 224.0.0.13, and the router with the lowest priority is elected as the DR for that segment.