Case study: Multicast

- [Instructor] On a network, one of the reasons…for network congestion may very well be multicast traffic.…Now multicast is one to many that are listening…and if you aren't managing that multicast traffic…by using IGMP, or Internet Group Message Protocol,…you may very well have multicasting go across…the entire network.…Now multicast header doesn't have a destination…IP address, and let's take a look.…

There is one of your SSDP packets,…which is a multicast, and there's EIGRP.…Just going to double click that and so you can…take a look at that.…Now this a protocol used to talk to other routers…but here you can see the destination, 224.0.0.10,…and that is the default multicast IP address for EIGRP.…Now, that 224 range is a class d.…

When you're using IP version four,…that range is simply for multicast.…So when we take a look at multicast traffic…the original idea of multicast is that it will…just simply go to the device that's listening…and to nowhere else, but as you can see…a lot of devices, if they're not tuned,…