Abstract: Mechanisms which examine a network of transparent bridges for establishing a specific path for each new TCP connection established between two terminals. The path is initiated by the edge bridge connected to the source terminal upon receiving a TCP segment of the type SYN for establishing a TCP connection, with the segment being encapsulated inside a special path request packet which is transmitted by all the network links to the destination edge bridge. The path is confirmed by the edge bridge of the destination terminal by means of a unicast acceptance packet which transports the response SYN+ACK segment from the terminal B in an encapsulated manner, confirming both the TCP connection between terminals and the path chosen between A and B. The path is automatically cleared when a particular time passes without the connection being used or when the terminal sends a FIN segment in both directions of the connection.

Abstract: A method operates at the data link level. Each bridge associates, during a guard time, the port through which a frame is first received with a source MAC address until a unicast reply frame confirms the matching two-way path between the source and destination addresses. Any frame from the same source received through another different port is discarded. Each bridge forwards the received broadcast frames through the rest of the ports, except those involving prohibited (down-up) turns, and deviates (or optionally returns) the unicast frames with an unknown or aged destination address through the spanning tree. The protocol can operate with encapsulation in the border bridges or without encapsulation, using in this case the replacement of universal MAC addresses in the border bridges with local MAC addresses. The establishment and control of paths can optionally be performed proactively by the border bridges, especially the bridges connected to servers.