Queue control method and system

A computer-readable medium, on which is stored a computer program of instructions for a processor to schedule fixed size traffic elements for transmission on a link from a number of queues, each queue having an assigned weight determined in dependence on predetermined characteristics of the queue and an associated calculation remainder variable, the program being arranged to generate and maintain a linear array in a memory, each array index corresponding to a transmission priority and being capable of referencing a list of queues, queues referenced by a low value array index being selected for transmission before queues referenced by higher value array index, wherein the program comprises, in combination:

• means for selecting the first queue referenced by the lowest array index for transmission and,
• means for moving the reference to the queue selected for transmission to a new array index, wherein the means for moving calculates the new array index by a predetermined function using the current array index referencing the queue, the queue's weight and the queue's calculation remainder variable value as parameters.

A field programmable gate array programmed to execute scheduling of fixed size traffic elements for transmission on a link from a number of queues, each queue having an assigned weight determined in dependence on predetermined characteristics of the queue and an associated calculation remainder variable, the array being arranged to generate and maintain a linear array in a memory, each array index corresponding to a transmission priority and being capable of referencing a list of queues, queues referenced by a low value array index being selected for transmission before queues referenced by higher value array index, wherein the program comprises the steps of:

• selecting the first queue referenced by the lowest array index for transmission and,
• moving the reference to the queue selected for transmission to a new array index, wherein the program calculates the new array index by a predetermined function using the current array index referencing the queue, the queue's weight and the queue's calculation remainder variable value as parameters.

An application specific integrated circuit configured to execute scheduling of fixed size traffic elements for transmission on a link from a number of queues, each queue having an assigned weight determined in dependence on predetermined characteristics of the queue and an associated calculation remainder variable, the circuit being arranged to generate and maintain a linear array in a memory, each array index corresponding to a transmission priority and being capable of referencing a list of queues, queues referenced by a low value array index being selected for transmission before queues referenced by higher value array index, wherein the program comprises the steps of:

• selecting the first queue referenced by the lowest array index for transmission and,
• moving the reference to the queue selected for transmission to a new array index, wherein the program calculates the new array index by a predetermined function using the current array index referencing the queue, the queue's weight and the queue's calculation remainder variable value as parameters.

A queue control system for scheduling fixed size traffic elements for transmission on a link from a number of queues, each queue having an assigned weight and an associated calculation remainder variable stored in a memory, the system comprising a memory storing a linear array, each array index corresponding to a transmission priority and being capable of referencing a list of queues, queues referenced by a low value array index being selected for transmission before queues referenced by higher value array index, and a queue processor arranged to repetitively select a queue for transmission in dependence on each queue's referenced position in the array, wherein the queue processor is arranged to operate a predetermined function for moving the reference to the queue selected for transmission to a new array index, the new array index being calculated using the current array index referencing the queue, the queue's weight and the queue's calculation remainder variable value as parameters.