Method of allocating bandwidth on request to the stations of a local area network

A method for dynamic bandwidth management in a logical ring network, the method comprising:

• circulating a token frame among a plurality of workstations;
• adjusting a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• adjusting the transmission size credit (C) in response to a committed information rate (CIR) variable associated with a bandwidth class;
• assigning a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class;
• assigning a bandwidth class to at least one of the plurality of workstations;
• limiting a maximum value of the transmission size credit (C) to a predefined transmission burst (TB) parameter;
• and
• transmitting a frame, or a series of frames, from one of the plurality of workstations as long as the transmission size credit (C) is equal to or greater than the frame size (FS) of the frame, or the series of frames, to be transmitted.

An apparatus for dynamic bandwidth management in a logical ring network, the apparatus comprising:

• a ring master module configured to circulate a token frame among a plurality of workstations;
• a TRTT adjustment module configured to adjust a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• a CIR adjustment module configured to adjust the transmission size credit (C) in response to a committed information rate (CR) variable associated with a bandwidth class;
• and
• a CIR assignment module configured to assign a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class.

An apparatus for dynamic bandwidth management in a logical ring network, the apparatus comprising:

• a ring master module configured to circulate a token frame among a plurality of workstations;
• a TRTT adjustment module configured to adjust a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• a CIR adjustment module configured to adjust the transmission size credit (C) in response to a committed information rate (CIR) variable associated with a bandwidth class;
• a CIR assignment module configured to assign a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class;
• a subscription module configured to assign a bandwidth class to at least one of the plurality of workstations;
• a TB module configured to limit a maximum value of the transmission size credit (C) to a predefined transmission burst (TB) parameter;
• and
• a transmission module configured to transmit a frame, or a series of frames, from one of the plurality of workstations as long as the transmission size credit (C) is equal to or greater than the frame size (FS) of the frame, or the series of frames, to be transmitted.

A system for dynamic bandwidth management in a logical ring network, the system comprising:

• a logical ring network;
• at least one workstation connected to the logical ring network and associated with a bandwidth class;
• a ring master station connected to the logical ring and configured to circulate a token frame among the workstations connected to the logical ring network;
• a token frame including a set of bandwidth classes and a corresponding set of CIR variables;
• and
• a transmission size credit (C) associated with a committed information rate (CIR) variable, a maximum value of the credit (C) limited to a predefined transmission burst (TB) parameter.

A workstation for dynamic bandwidth management in a logical ring network, the workstation comprising:

• a subscription module configured to subscribe the workstation to a bandwidth class associated with a guaranteed information rate based on a committed information rate (CIR) variable corresponding to the subscribed bandwidth class;
• a token frame module configured to receive a token frame from a ring master station, the token frame including a value for the CIR variable corresponding to the subscribed bandwidth class of the workstation;
• and
• a transmission module configured to transmit a frame, or a series of frames, from the workstation as long as the transmission size credit (C) is equal to or greater than the frame size (FS) of the frame, or the series of frames, to be transmitted.

A ring master station for dynamic bandwidth management in a logical ring network, the ring master station comprising:

• a ring master module configured to circulate a token frame among a plurality of workstations;
• a TRTT adjustment module configured to adjust a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• a CIR adjustment module configured to adjust the transmission size credit (C) in response to a committed information rate (CIR) variable associated with a bandwidth class;
• a CIR assignment module configured to assign a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class;
• and
• a TB module configured to limit a maximum value of the transmission size credit (C) to a predefined transmission burst (TB) parameter.

An apparatus for dynamic bandwidth management in a logical ring network, the apparatus comprising:

• means for circulating a token frame among a plurality of workstations;
• means for adjusting a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• means for adjusting the transmission size credit (C) in response to a committed information rate (CIR) variable associated with a bandwidth class;
• means for assigning a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class;
• means for assigning a bandwidth class to at least one of the plurality of workstations;
• means for limiting a maximum value of the transmission size credit (C) to a predefined transmission burst (TB) parameter;
• and
• means for transmitting a frame, or a series of frames, from one of the plurality of workstations as long as the transmission size credit (C) is equal to or greater than the frame size (FS) of the frame, or the series of frames, to be transmitted.

Acomputer program product for dynamic bandwidth management in a logical ring network, the computer program product comprising computer readable medium having a computer program code configured to conduct the steps of:

• circulating a token frame among a plurality of workstations;
• adjusting a transmission size credit (C) in response to a token round trip time (TRTT) variable;
• adjusting the transmission size credit (C) in response to a committed information rate (CIR) variable associated with a bandwidth class;
• and
• assigning a value for the CIR variable based on a total network bandwidth, the bandwidth class of each of the plurality of workstations, and a predefined coefficient K associated with the bandwidth class.