Telex IP-223 technical manual Internet Group Management Protocol Igmp, Network Performance

Communications System Design

NOTE: When using Cisco technology, IP PIM dense mode is generally recommended. Generally speaking, sparse- dense-modecan also be implemented effectively. We recommend explicitly joining the multicast group with an IP IGMP static-join X.X.X.X command. For more information on Cisco and IGMP, visit www.cisco.com

Internet Group Management Protocol (IGMP)

IGMP can be used to control where multicast is allowed to propagate. When a console on the subnet is expected to be continually operational, multicast must be active for that subnet at all times.

Network Performance

Networks should perform well under any loading conditions. The default audio delay is 120ms, plus any delay added by the network. While delay alone does not cause issues, variable delay (jitter) does. Jitter in a network cannot exceed the maximum packet buffer of any individual product buffer. Refer to the individual product manuals for these specifications. For example, the IP-223 can handle approximately 600ms of network jitter.

NOTE: Losing more than 5% of the total packets transmitted compromises audio quality and system performance. Optimally, packet loss should be less than 1%.

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