公开(公告)号：JPH10276220A

公开(公告)日：1998-10-13

申请号：JP5633098

申请日：1998-03-09

Applicant: IBM

Inventor： DELP GARY SCOTT ,  LEICHTY PHILIP LYNN

IPC: H04Q3/00 ,  H04L12/56 ,  H04L12/28

Abstract: PROBLEM TO BE SOLVED: To provide the method and device for scheduling transmission of cells in a data stream through a communication network. SOLUTION: In the case that a best effort scheduler includes pluralities of timing wheels, the priority of a best effort timing wheel is placed lower than the priority of the others. Data of each data stream are stored in a corresponding data queue. A next object transfer time of each data cell queue is calculated by using a prescribed logic channel descriptor parameter. A timing wheel with lower or higher priority is selected, a time slot of a timing wheel is calculated based on an identified object transmission time of each active data cell queue, an active indication is set and an entry pointing out a corresponding data cell queue is stored. A relative speed between data streams is maintained but the absolute speed is adjusted in a wheel with lower priority.

公开(公告)号：GB2341751A

公开(公告)日：2000-03-22

申请号：GB9928907

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  FIROIU VICTOR ,  GUERIN ROCH ANDRE ,  LEICHTY PHILIP LYNN ,  POULTER DAVID RICHARD ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN ,  SHAFFER JOHN HANDLEY

IPC: H04L12/70 ,  H04Q11/04 ,  H04L12/56

Abstract: A method and apparatus are provided for scheduling the transmission of cells of a plurality of data streams in a communications network. A multiple tier cell scheduler is provided that includes at least two scheduling timing wheels. The priority of a first timing wheel is higher than the priority of a second timing wheel. The priority of the second timing wheel is higher than the priority of an optional third timing wheel. The third timing wheel includes a best effort operational mode. The relative rates between data streams are maintained, while the absolute rates of the data streams are increased or decreased in the lowest priority wheel.

公开(公告)号：GB2324679B

公开(公告)日：2001-11-28

申请号：GB9804624

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  LEICHTY PHILIP LYNN

IPC: H04Q3/00 ,  H04L12/56 ,  H04Q11/04

Abstract: A method and apparatus are provided for scheduling the transmission of cells of a plurality of data streams in a communications network. A best effort scheduler is provided for scheduling the transmission of cells of a plurality of data streams in a communications network. The best effort scheduler includes a best effort operational mode and can include more than one timing wheel. When the best effort scheduler includes more than one timing wheel, then the priority of the best effort timing wheel is lower than the priority of the other timing wheel or wheels. Data of each data stream is enqueued to a corresponding data cell queue. A target next transmission time for each data cell queue is calculated utilizing predetermined logical channel descriptor parameters. A lower priority or a higher priority timing wheel is selected and a timing wheel time slot is calculated based on an identified target transmission time for each active data cell queue. An active indication is set for the identified timing wheel time slot and an entry is stored to point to the corresponding data cell queue for the identified timing wheel time slot. The relative rates between data streams are maintained, while the absolute rates of the data streams are increased or decreased in the low priority wheel. Scheduling opportunities can be defined utilizing a predefined pseudo data cell queue. Then the calculation of the target transmission time for each data cell queue includes the predefined pseudo data cell queue, and the identified target transmission time for the predefined pseudo data cell queue defines scheduling opportunities of multiple timing wheel time slots.

公开(公告)号：GB2324679A

公开(公告)日：1998-10-28

申请号：GB9804624

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  LEICHTY PHILIP LYNN

IPC: H04Q3/00 ,  H04L12/56 ,  H04Q11/04

Abstract: A method and apparatus are provided for scheduling the transmission of cells of a plurality of data streams in a communications network. A best effort scheduler is provided for scheduling the transmission of cells of a plurality of data streams in a communications network. The best effort scheduler includes a best effort operational mode and can include more than one timing wheel. When the best effort scheduler includes more than one timing wheel, then the priority of the best effort timing wheel is lower than the priority of the other timing wheel or wheels. Data of each data stream is enqueued to a corresponding data cell queue. A target next transmission time for each data cell queue is calculated utilizing predetermined logical channel descriptor parameters. A lower priority or a higher priority timing wheel is selected and a timing wheel time slot is calculated based on an identified target transmission time for each active data cell queue. An active indication is set for the identified timing wheel time slot and an entry is stored to point to the corresponding data cell queue for the identified timing wheel time slot. The relative rates between data streams are maintained, while the absolute rates of the data streams are increased or decreased in the low priority wheel. Scheduling opportunities can be defined utilizing a predefined pseudo data cell queue. Then the calculation of the target transmission time for each data cell queue includes the predefined pseudo data cell queue, and the identified target transmission time for the predefined pseudo data cell queue defines scheduling opportunities of multiple timing wheel time slots.

公开(公告)号：GB2341751B

公开(公告)日：2000-08-09

申请号：GB9928907

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  FIROIU VICTOR ,  GUERIN ROCH ANDRE ,  LEICHTY PHILIP LYNN ,  POULTER DAVID RICHARD ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN ,  SHAFFER JOHN HANDLEY

IPC: H04L12/70 ,  H04Q11/04 ,  H04L12/56

公开(公告)号：GB2324678B

公开(公告)日：2000-05-24

申请号：GB9804618

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  FIROIU VICTOR ,  GUERIN ROCH A ,  LEICHTY PHILIP LYNN ,  POULTER DAVID RICHARD ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN ,  SHAFFER JOHN HANDLEY

IPC: H04Q3/00 ,  H04L12/56 ,  H04Q11/04

Abstract: A method and apparatus are provided for scheduling the transmission of cells of a plurality of data streams in a communications network. An earliest deadline first (EDF) scheduler is provided for scheduling the transmission of cells of a plurality of data streams in a communications network to ensure that the connection or data stream with the earliest deadline is transmitted first. Each of the multiple data streams has a delay bound or deadline. Data of each data stream is enqueued to a corresponding data cell queue. A timing wheel time slot based on an identified target transmission time for each data cell queue is calculated utilizing an addition of a maximum delay value. A move forward timing mechanism includes a scan forward feature to identify a succession of virtual connection or data stream cell queues for transmission. A multiple tier cell scheduler is provided that includes at least two scheduling timing wheels. The priority of a first timing wheel is higher than the priority of a second timing wheel. The priority of the second timing wheel is higher than the priority of an optional third timing wheel. The third timing wheel includes a best effort operational mode. The relative rates between data streams are maintained, while the absolute rates of the data streams are increased or decreased in the lowest priority wheel.

公开(公告)号：GB2324678A

公开(公告)日：1998-10-28

申请号：GB9804618

申请日：1998-03-05

Applicant: IBM

Inventor： DELP GARY SCOTT ,  FIROIU VICTOR ,  GUERIN ROCH A ,  LEICHTY PHILIP LYNN ,  POULTER DAVID RICHARD ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN ,  SHAFFER JOHN HANDLEY

IPC: H04Q3/00 ,  H04L12/56 ,  H04Q11/04

Abstract: A method and apparatus are provided for scheduling the transmission of cells of a plurality of data streams in a communications network. An earliest deadline first (EDF) scheduler is provided for scheduling the transmission of cells of a plurality of data streams in a communications network to ensure that the connection or data stream with the earliest deadline is transmitted first. Each of the multiple data streams has a delay bound or deadline. Data of each data stream is enqueued to a corresponding data cell queue. A timing wheel time slot based on an identified target transmission time for each data cell queue is calculated utilizing an addition of a maximum delay value. A move forward timing mechanism includes a scan forward feature to identify a succession of virtual connection or data stream cell queues for transmission. A multiple tier cell scheduler is provided that includes at least two scheduling timing wheels. The priority of a first timing wheel is higher than the priority of a second timing wheel. The priority of the second timing wheel is higher than the priority of an optional third timing wheel. The third timing wheel includes a best effort operational mode. The relative rates between data streams are maintained, while the absolute rates of the data streams are increased or decreased in the lowest priority wheel.