Mitigation

• Do not use topologies that intentionally employ loops when their use can be avoided.
• Check for the presence of, and remove any, unintended loops.
• Do not use Rapid Spanning Tree (RSTP or MSTP). Use STP.
• Use switches that allow port based bandwidth throttling or data storm control. The configuration of a throttling feature will be switch vendor specific. Configure each port directly connected to a CobraNet device to limit the amount of traffic allowed to go from the port to the CobraNet device.
  • Data storm control often consists of severely limiting or stopping multicast data. Be sure that this feature is not configured to prevent the passage of normally occurring multicast CobraNet data which includes beat packets, reservation packets and multicast bundles.
  • A good rule is to limit traffic going to a CobraNet device to 50 megabits. Less traffic may be acceptable and safe depending on the number of bundles and channels received by a device. More than 50 Mbit of bandwidth will seldom be required when using CM-1 modules.
  • The specific bandwidth to allow should be the amount of received data plus approximately 10 to 15 megabits
  • A CM-1, when fully configured to receive 32 channels of 48 kHz sample rate audio data at standard latency, will receive approximately 32 Mbit of audio data + beat packets + SNMP + serial or packet bridge. The additional 10~15 Mbit is intended to accommodate data other than audio bundles.
  • Additional requirements for bandwidth will be created by the use of:

    Lower latencies – approx +10% per decrease in latency

    96 kHz sample rate - doubles the required bandwidth per channel

    Packet bridge – use dependant

    Serial bridge – use dependant

    SNMP – use dependant.