IGMP Implementation

GarrettCom’s IGMP-L2 software feature offers a simple alternative for managing multiple IP video surveillance cameras and monitors within an industrial site. IGMP-L2 is an enhancement of the industry-standard Internet Group Management Protocol, IGMP, which is used to direct multicast video feeds only to where they are needed, pruning unnecessary traffic and thus preserving network bandwidth. IGMP-L2 (patent # 7,512,146) provides the same capabilities, but using a simplified approach. While IGMP requires ISO Layer 3 central-office routers, IGMP-L2 needs only ISO Layer 2 6K Series industrial-grade Ethernet switches. The difference is that the IGMP-L2 user in industrial applications is relieved from the Layer 3 office-grade routers with their added complexity and expense. IGMP-L2, which is integrated into GarrettCom’s highly regarded MNS-6K network management software for managed Ethernet Switches, is available with Release 3.5 and higher.

IP video cameras typically “multicast” packets of information, such as streaming video, to selected destinations using a single virtual network connection. Prior to the release of IGMP-L2, Layer 2 switches were only able to manage “unicast” packets, which require the source to send multiple identical packets, one to each potential destination, consuming (and wasting) massive amounts of bandwidth. With IGMP-L2, managed 6K Magnum Layer 2 switches can selectively manage multicast streaming video feeds, so that only the video feeds selected go over the network when and to where they are requested.

• IGMP provides critical filtering for video applications
• Layer 3 (router) performs “querier” role
• Clients subscribe to multicast sessions (video streams)
• Layer 2 switches snoop IGMP messages
• Multicast traffic is only forwarded “towards” subscribers
• Tremendous bandwidth savings – critical to network operation