Which Protocol Independent Multicast (PIM) mode is designed for large, densely populated multicast groups?

The mode of Protocol Independent Multicast designed specifically for large, densely populated multicast groups is Dense Mode. In this configuration, the network assumes that multicast receivers are present in all parts of the network. As a result, Dense Mode creates a multicast distribution tree quickly and aggressively floods multicast traffic through the network. If a branch of the network does not have any receivers, the traffic is pruned away.

This approach to managing multicast traffic is effective in scenarios where a large number of hosts are likely to be interested in the multicast content, allowing for efficient data distribution. Dense Mode is particularly beneficial when the multicast groups are large and the members are densely located in the same network segment, thereby minimizing the need for complex management related to source and receiver memberships.

In contrast, the other modes such as Sparse Mode focus on situations where multicast receivers are more sporadic, which can lead to a different handling strategy that relies on explicit join requests or uses a more controlled forwarding technique. Source-Specific Multicast is tailored for scenarios where traffic originates from specific sources to specific receivers rather than supporting large, densely populated multicast topology efficiently.

Therefore, Dense Mode is the most appropriate choice for large, densely populated multicast groups.