公开(公告)号：US6134217A

公开(公告)日：2000-10-17

申请号：US632680

申请日：1996-04-16

申请人： Dimitrios Stiliadis ,  Anujan Varma

发明人： Dimitrios Stiliadis ,  Anujan Varma

IPC分类号： H04L12/56 ,  H04Q11/04

CPC分类号： H04Q11/0478 ,  H04L49/3081 ,  H04L2012/5649 ,  H04L2012/5651 ,  H04L2012/5679 ,  H04L2012/5681

摘要： A traffic scheduling system and method are disclosed for providing quality-of-service (QoS) guarantees in a packet-switched communication network where multiple traffic sessions share an outgoing communication link of a network switch in such a way that a certain minimum rate is reserved for each session sharing the link. The method can be applied to both general communication networks supporting variable packet sizes and Asynchronous Transfer Mode (ATM) networks with a fixed packet (cell) size. A packet arriving for transmission on an outgoing link of the switch is assigned a timestamp and placed in a priority queue in the order of increasing timestamps so that the packet with the smallest timestamp is placed at the head of the queue. The timestamp is computed based on a system potential maintained by the system, that tracks the progress of work in the system. The system potential is maintained at zero when no packets are queued at the outgoing link, and increases progressively as packets are transmitted. In addition to the timestamps, a starting potential is also calculated on arrival of each packet, and the starting potentials of queued packets are maintained in a separate priority queue, in the order of increasing starting potentials so that the smallest starting potential value appears at the head of the queue. This smallest starting potential is used to recalibrate the system potential at the end of transmission of each packet, by setting the system potential to the smallest starting potential.

摘要翻译： 公开了一种用于在分组交换通信网络中提供服务质量（QoS）保证的业务调度系统和方法，其中多个业务会话共享网络交换机的输出通信链路，使得某个最小速率被保留 为每个会话共享链接。 该方法可以应用于支持可变分组大小的通用通信网络和具有固定分组（小区）大小的异步传输模式（ATM）网络。 分配到交换机的出站链路上传输的分组被分配时间戳，并以增加时间戳的顺序放置在优先级队列中，使得具有最小时间戳的分组被放置在队列的头部。 时间戳是基于系统维护的系统潜力来计算的，跟踪系统中的工作进度。 当没有分组在出站链路排队时，系统电位保持为零，并随着数据包的传输而逐渐增加。 除了时间戳之外，还在每个分组的到达时计算起始电位，并且排队分组的起始电位按照增加启动电位的顺序被保持在单独的优先级队列中，使得最小起始电位值出现在 队长。 这个最小的起始电位用于通过将系统电位设置为最小的起始电位来重新校准每个数据包传输结束时的系统电位。

公开(公告)号：US5859835A

公开(公告)日：1999-01-12

申请号：US634904

申请日：1996-04-15

申请人： Anujan Varma ,  Dimitrios Stiliadis

发明人： Anujan Varma ,  Dimitrios Stiliadis

IPC分类号： H04L12/56 ,  H04Q11/04 ,  H04J3/14

CPC分类号： H04L49/3081 ,  H04Q11/0478 ,  H04L2012/5649 ,  H04L2012/5651 ,  H04L2012/5679 ,  H04L2012/5681

摘要： A traffic scheduling system and method for packet-switched communications networks where multiple sessions share an outgoing communications link. Prior to transmission on the outgoing link, packets are assigned a time-stamp and placed into a priority queue in order of ascending time-stamps so that the packet with the smallest time-stamp is placed at the head of the queue. The time-stamp assigned to a particular packet is calculated as the estimated time at which the last bit of the packet is transmitted in an ideal system, using a global variable called the system potential which tracks the progress of work in the scheduling system. The system potential is recalibrated periodically to avoid any long-term unfairness in service offered to the sessions sharing the outgoing link.

摘要翻译： 一种用于分组交换通信网络的业务调度系统和方法，其中多个会话共享出站通信链路。 在传出链路之前传输数据包的时间戳并按照升序排列顺序排列在优先级队列中，这样最小时间戳的数据包就被置于队列的头部。 分配给特定分组的时间戳被计算为在理想系统中使用称为系统电位的全局变量在跟踪调度系统中的工作进度的分组的最后一位的估计时间。 定期重新校准系统潜力，以避免向共享传出链接的会话提供的服务长期不公平。