US Patent 7894341 Switch protocol for network communications

A switch protocol for network communications (particularly but not exclusively for multiple computer systems) is disclosed in which each switch maintains a list of addresses which can be reached via each port of the switch. In addition, prior to delivering a message or packet to a port, the switch deletes any address in the message or packet which is unable to be reached via that port. The arrangement saves the repetitive sending of uni-cast messages and also saves broadcast messages being sent via the switches to computers which are not intended to receive the messages. Various networked topologies are also disclosed.