公开(公告)号：JP2000324159A

公开(公告)日：2000-11-24

申请号：JP12005899

申请日：1999-04-27

Applicant: IBM

Inventor： GUERIN ROCH A ,  KAMAT SANJAY DAMODAR ,  PAN PING P ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN

IPC: H04L12/813 ,  H04L12/835 ,  H04L12/56

Abstract: PROBLEM TO BE SOLVED: To give assurance of rate to every flow with no advanced scheduler required by deciding whether a stream should be accepted or not according to whether a sufficient buffer space is available in order to allocate the stream. SOLUTION: A router 102 checks whether the link capacity and a buffer space sufficient to satisfy a request are available or not to decide whether the request should be accepted. A deciding logic circuit of the router 102 calculates the 1st sum by adding a current receiving packet to an exclusive part of a total buffer space and decides whether the 1st sum exceeds the 1st threshold to set a 1st variable. Then the 2nd sum is calculated by adding the current receiving packet to a buffer space that is allocated to a stream (n) and a 2nd variable is set after it is decided whether the 2nd sum exceeds the 2nd threshold. Thus, a packet is accepted or rejected according to the 1st and 2nd variables.

公开(公告)号：JP2000049853A

公开(公告)日：2000-02-18

申请号：JP12007599

申请日：1999-04-27

Applicant: IBM

Inventor： GUERIN ROCH A ,  KAMAT SANJAY DAMODAR ,  PAN PING P ,  PERIS VINOD GERARD JOHN ,  RAJAN RAJENDRAN

IPC: H04L12/56 ,  H04Q11/04

Abstract: PROBLEM TO BE SOLVED: To obtain the method for providing a rate warrant to respective flows or a flow group in a router by a sophisticated function management of a buffer. SOLUTION: A rate warrant is provided by wisely assigning and separating a buffer usable for each flow. In the most fundamental mode, this method is applied to an output queue network system provided with a simple FIFO scheduler that multiplexes some streams using rate reservation and is going to transmit the multiplexed streams to an output link. This method strictly divides the buffer into some parts reserved strictly for each flow in proportion to link reservation. Thus, each stream is warranted to acquire the link reservation rate by the scalable method. In a specific embodiment of this system, part of the buffer is divided strictly and the streams can completely access the remaining areas of the buffer.

公开(公告)号：DE69327692T2

公开(公告)日：2000-07-06

申请号：DE69327692

申请日：1993-08-24

Applicant: IBM

Inventor： AHMADI HAMID ,  GUERIN ROCH A ,  DERBY JEFFREY HASKELL ,  GUN LEVENT ,  MARIN GERALD ARNOLD ,  NAGHSHINEH MAMOUD ,  SOHRABY KHOSROW

IPC: H04L29/06 ,  H04L12/56

Abstract: A congestion control system for packet communications networks in which access to the network is controlled to prevent such congestion. Packets within the pre-specified statistical description of each packet source are marked as high priority ("green" packets) while packets exceeding the pre-specified characteristics are marked with a lower priority ("red" packets). The overall red packet rate is limited to prevent red packet saturation of the network. The introduction of red packets into the network is subjected to a degree of hysteresis to provide better interaction with higher layer error recovery protocols. The amount of hysteresis introduced into the red packet marking can be fixed or varied, depending on the statistics of the incoming data packets at the entry point to the network.

公开(公告)号：DE69327692D1

公开(公告)日：2000-03-02

申请号：DE69327692

申请日：1993-08-24

Applicant: IBM

Inventor： AHMADI HAMID ,  GUERIN ROCH A ,  DERBY JEFFREY HASKELL ,  GUN LEVENT ,  MARIN GERALD ARNOLD ,  NAGHSHINEH MAMOUD ,  SOHRABY KHOSROW

IPC: H04L29/06 ,  H04L12/56

Abstract: A congestion control system for packet communications networks in which access to the network is controlled to prevent such congestion. Packets within the pre-specified statistical description of each packet source are marked as high priority ("green" packets) while packets exceeding the pre-specified characteristics are marked with a lower priority ("red" packets). The overall red packet rate is limited to prevent red packet saturation of the network. The introduction of red packets into the network is subjected to a degree of hysteresis to provide better interaction with higher layer error recovery protocols. The amount of hysteresis introduced into the red packet marking can be fixed or varied, depending on the statistics of the incoming data packets at the entry point to the network.

公开(公告)号：CA2142029C

公开(公告)日：2001-12-25

申请号：CA2142029

申请日：1995-02-07

Applicant: IBM

Inventor： GEORGIADIS LEONIDAS ,  GUERIN ROCH A ,  SHAVITT YUVAL Y ,  SLATER ANDREW E ,  CIDON ISRAEL

IPC: G06F13/00 ,  H04L12/433 ,  H04L12/28

Abstract: A non-quota access indicator is circulated among nodes in a multi-node quota based communication system with a shared resource, indicating maximum possible non - quota access to the shared resource to a given node receiving same. Upon arrival at a nod e, the indicator is saved and then updated to reflect the current status of that node as either starved or satisfied, the former being a condition of currently having quota remaining and a share d resource access requirement, and the latter being a condition of either currently having no remaining quota or having no current shared resource access requirement. After updating, the no de immediately propagates the indicator to the next node in the system. When a node without quota requires access to the shared resource, it compares its requirement to the last store d indicator and accesses the shared resource if the stored indicator is equal to or greater than the access requirement.

公开(公告)号：CA2142030C

公开(公告)日：2001-07-03

申请号：CA2142030

申请日：1995-02-07

Applicant: IBM

Inventor： CIDON ISRAEL ,  GEORGIADIS LEONIDAS ,  GUERIN ROCH A ,  SHAVITT YUVAL Y ,  SLATER ANDRES E

IPC: G06F13/00 ,  H04L12/433 ,  H04L12/56 ,  H04L12/28

Abstract: A counter for tracking current shared resource access quota requests of node s in a mufti-node system is circulated among the nodes. A quota for a given node is determined as a function of the counter, the needs of the given node and a variable indicative of total access quota for all nodes combined. The determined quota is then allocated to the given node, i.e.; the node is allowed to access the shared resource in accordance with the determined quot a.

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：DE69328380D1

公开(公告)日：2000-05-18

申请号：DE69328380

申请日：1993-12-31

Applicant: IBM

Inventor： ILIADIS ILIAS ,  GUERIN ROCH A

IPC: H04Q3/00 ,  H04L12/70 ,  H04L12/801 ,  H04Q11/04 ,  H04L12/56

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.

公开(公告)号：CA2142029A1

公开(公告)日：1995-08-08

申请号：CA2142029

申请日：1995-02-07

Applicant: IBM

Inventor： CIDON ISRAEL ,  GEORGIADIS LEONIDAS ,  GUERIN ROCH A ,  SHAVITT YUVAL Y ,  SLATER ANDREW E

IPC: G06F13/00 ,  H04L12/433 ,  H04L12/28

Abstract: A non-quota access indicator is circulated among nodes in a multi-node quota based communication system with a shared resource, indicating maximum possible non - quota access to the shared resource to a given node receiving same. Upon arrival at a nod e, the indicator is saved and then updated to reflect the current status of that node as either starved or satisfied, the former being a condition of currently having quota remaining and a share d resource access requirement, and the latter being a condition of either currently having no remaining quota or having no current shared resource access requirement. After updating, the no de immediately propagates the indicator to the next node in the system. When a node without quota requires access to the shared resource, it compares its requirement to the last store d indicator and accesses the shared resource if the stored indicator is equal to or greater than the access requirement.