Method and apparatus for enabling flow control over multiple networks having disparate flow control capability

A method of extending a lower layer flow control protocol from an intermediate network to host networks interfacing to said intermediate network, wherein said intermediate network supports said lower layer flow control protocol and said host networks interfacing to said intermediate network support a transport layer flow control, said method comprising:

• receiving a transport layer flow control message at a first element of said intermediate network from one of said host networks;
• propagating said received transport layer flow control message through said intermediate network to a second element;
• selectively modifying said received transport layer flow control message based upon intermediate network lower layer flow control information;
• and
• forwarding said modified transport layer flow control message to another of said host networks.

An internetwork in which intermediate network lower layer flow control is extended between host networks supporting higher layer flow control, comprising:

• plural host networks supporting higher layer flow control therebetween;
• and
• at least one intermediate network interconnecting said plural host networks and supporting lower layer flow control, each of said at least one intermediate networks comprising
• a first node for receiving higher layer flow control information from a first of said plural host networks,
• circuitry for selectively modifying said received higher layer flow control information based on said received higher layer flow control information, previously received higher layer flow control information, and intermediate network lower layer flow control status, and
• a second node for forwarding said selectively modified higher layer flow control information to a second of said plural host networks.

A network device operable to interface a first network, supporting a lower layer flow control protocol, to at least one second network, supporting a higher layer flow control protocol, said device comprising:

• buffers for storing
• higher layer flow control information originated by at least one device in said second network, and
• lower layer flow control status associated with said first network responsive to said lower layer flow control protocol;
• circuitry for analyzing said stored higher layer flow control information, for analyzing said lower layer flow control status, and for selectively modifying said higher layer flow control information based upon said analyses;
• and
• a forwarding element for forwarding said selectively modified higher layer flow control information to said second network.

A network device operable to interface a first network supporting a first flow control protocol to at least one second network supporting a transport layer flow control protocol, said device comprising:

• buffers for storing
• transport layer flow control information originated by at least one device in said second network, and
• first flow control protocol status associated with said first network responsive to said first flow control protocol;
• circuitry for analyzing said stored transport layer flow control information, for analyzing said first flow control protocol status, and for selectively modifying said transport layer flow control information based upon said analyses;
• and
• a forwarding element for forwarding said selectively modified transport layer flow control information to said at least one second network.

A network device operable to interface a first network supporting a first flow control protocol to at least one second network supporting a second flow control protocol, said device comprising:

• buffers for storing
• second flow control protocol information originated by at least one device in said second network, and
• first flow control protocol status associated with said first network responsive to said first flow control protocol;
• circuitry for analyzing said stored second flow control protocol information, for analyzing said first flow control protocol status, and for selectively modifying said second flow control protocol information based upon said analyses;
• and
• a forwarding element for forwarding said selectively modified second flow control protocol information to said at least one second network.