Distributed port-blocking method

A method of blocking ports to prevent formation of active loops in a network, comprising:

• determining topology information of the network;
• determining whether one or more specific ports of the network are currently active;
• and
• determining which port should be active, based on the determined topology information and based on whether the one or more specific ports of the network are currently active.

A method of blocking ports to prevent formation of active loops in a network, comprising:

• determining topology information of the network;
• determining one or more parameters of the network;
• blocking a first group of ports responsive to the determined one or more parameters of the network and responsive to the determined topology information;
• changing at least one of the one or more parameters of the network responsive to the blocking of the first group of ports;
• and
• determining whether to change the group of blocked ports responsive to the changed at least one of the one or more parameters.