Session Description : With AV over IP products depending more on multicast networks the need for advanced network troubleshooting is growing. This session will focus on IGMP Groups. Understanding the way multicast groups work can allow a designer and an AV installer to better deploy more robust mulitcast AV over IP networks. Most network switches also provide access to important multicast group information which can help resolve issues in the field. Appropriate vocabulary, technical background, and other key IGMP group information will be provided to the participants.