In order to prevent bridging loops, 48 IX takes stringent precautions to ensure uptime of the peering fabric. A bridging loop can easily bring down a given layer 2 domain, adversely affecting performance and availability of the attached network infrastructure. During a bridging loop (also commonly referred to as a broadcast storm), broadcast frames are looped back to the network, which creates continuous duplicate traffic, and can eventually overload the CPUs of all connected equipment.
48 IX uses MAC address filtering and persistent MAC learning (also commonly referred to as 'sticky MAC') to limit the MAC addresses allowed to communicate on a port to the first two learned when a port first comes online. The 48 IX Connection Agreement allows for connecting up to two routers to each member's port.
MAC Address Changes
If a MAC address change is needed, please contact 48 IX NOC by email or phone for immediate resolution.
Port Flap Dampening
In addition to port security, 48 IX also implements port flap dampening on all customer facing interfaces. If a port transitions from an Up to a Down state and back more than three times in five seconds, the port is disabled. After ten seconds it is automatically re-enabled.