Communications system and method for efficient management of bandwidth in a FDDI station

Claim 1

In a communications system for transferring real time synchronous and asynchronous data between a network and a host system, a communication adapter for efficient and dynamic management of bandwidth in a station included in the network comprising: a queue manager including a synchronous data threshold register and counter and an asynchronous data threshold register and counter; the queue manager controlling receiving or transmitting of the synchronous or asynchronous data at a first, a second and a third interfaces while keeping track of the synchronous and asynchronous data stored in separate queues of a storage means; the first interface coupled between a system bus and the queue manager, the first interface transmitting or receiving synchronous or asynchronous data to/from the host system and the second or the third interface according to instructions received from the host system or the queue manager; the second interface coupled between the storage means and the queue manager for storing synchronous and asynchronous data in separate queues, as directed by the queue manager; the third interface coupled between the network and the queue manager; the third interface processing all synchronous or asynchronous data received from the network for the host system or sent to the network by the host system; bandwidth control logic coupled to the queue manager, and the third interface; the bandwidth control unit specifying the amount of bandwidth available for synchronous data transmission to/from the network and the host system; means for dynamically switching between the transmission of synchronous and asynchronous data between the host system and the network, in real time, in either direction, while ensuring synchronous and asynchronous data bandwidth are not exceeded; and means for initiating token capture in the network before the synchronous or asynchronous data has been buffered in storage.

Claim 12

A method for efficient and dynamic management of bandwidth between a host system and (on) a station in a network comprising the steps of: (a) defining a condition "A" for transferring synchronous data between the network and the host system when a threshold is reached in a first register for receiving the synchronous data or one or more frames of synchronous data have been buffered in a storage means; (b) defining a condition "B" for transferring asynchronous data between the network and the host system when a threshold is reached in a second register for receiving the packet data or one or more frames of packet data have been buffered in the storage means; (c) programming a storage system bandwidth allocation register and counter with the amount of bandwidth available for synchronous and asynchronous data; (d) initiating capture of a token in the network when condition "A" or "B" has been detected on the system; (e) testing to determine if condition a "A" or "B" is true; (f) a "yes" condition initiating a test in the system bandwidth allocation counter to determine if the synchronous system bandwidth has expired; (g) a "yes" condition for the counter initiating a test for the "B" condition; (h) a "no" condition for the counter enabling the system bandwidth counter and transmitting one synchronous frame to the network; (i) disabling the system bandwidth counter and initiating a condition test after transmitting one synchronous frame; (j) a "yes" condition for an "A" condition test initiating step "(f)"; (k) a "no" condition for the condition test initiating step "(g)"; (l) performing a condition "B" test initiated by step f to determine if a token holder timer (THT) is less than or equal to a target token rotation timer (TTRT); (m) a "no" condition for the condition "B" test initiating a release of token operation; and (n) a "yes" condition for the condition "B" test initiating a transmission of one asynchronous frame and returning to step "(e)" after transmission of the asynchronous frame.

Claim 13

A method for efficient and dynamic management of bandwidth between a host system and (on) a station in a network comprising the steps of: (a) defining a condition "A" for transferring synchronous data between the network and the host system when a threshold is reached in a first register for receiving the synchronous data or one or more frames of synchronous data have been buffered in a storage means; (b) defining a condition "B" for transferring asynchronous data between the network and the host system when a threshold is reached in a second register for receiving the packet data or one or more frames of packet data have been buffered in the storage means; (c) programming a storage system bandwidth allocation register and counter with the amount of bandwidth available for synchronous and asynchronous data; (d) initiating capture of a token in the network when condition "A" or "B" has been detected on the system; (e) testing to determine if condition a "A" or "B" is true; (f) a "yes" condition initiating a test in the system bandwidth allocation counter to determine if the synchronous system bandwidth has expired; (g) a "yes" condition for the counter initiating a test for the "B" condition; (h) a "no" condition for the counter enabling the system bandwidth counter and transmitting one synchronous frame to the network; (i) disabling the system bandwidth counter and initiating a condition test after transmitting one synchronous frame; (j) a "yes" condition for an "A" condition test initiating step "(f)"; (k) a "no" condition for the condition test initiating step "(g)"; (l) performing a condition "B" test initiated by step f to determine if a token holder timer (THT) is less than or equal to a target token rotation timer (TTRT); (m) a "no" condition for the condition "B" test initiating a release of token operation; and (n) a "yes" condition for the condition "B" test initiating a transmission of one asynchronous frame and returning to step "(e)" after transmission of the asynchronous frame.