公开(公告)号：US6046981A

公开(公告)日：2000-04-04

申请号：US808128

申请日：1997-02-28

申请人： Gopalakrishnan Ramamurthy ,  Qiang Ren

发明人： Gopalakrishnan Ramamurthy ,  Qiang Ren

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

CPC分类号： H04L12/5602 ,  H04Q11/0478 ,  H04L2012/5632 ,  H04L2012/5651

摘要： A multi-class connection admission control (CAC) method that supports cell loss and delay requirements. In this model-based CAC, the source traffic is described in terms of the usage parameter control (UPC) parameters. Through analysis and approximations, simple closed-form methods to calculate the bandwidth required to meet guarantees on quality of service (QoS) are used. In addition to being robust, the CAC achieves a high level of resource utilization and can be easily implemented for real-time admission control.

摘要翻译： 一种支持信元丢失和延迟要求的多类连接准入控制（CAC）方法。 在该基于模型的CAC中，根据使用参数控制（UPC）参数来描述源流量。 通过分析和近似，使用简单的封闭形式方法来计算满足服务质量（QoS）保证所需的带宽。 除了稳健之外，CAC还实现了高水平的资源利用，并且可以轻松实现实时准入控制。

公开(公告)号：US5276677A

公开(公告)日：1994-01-04

申请号：US905287

申请日：1992-06-26

申请人： Gopalakrishnan Ramamurthy ,  Bhaskar Sengupta

发明人： Gopalakrishnan Ramamurthy ,  Bhaskar Sengupta

IPC分类号： H04L12/56 ,  H04Q11/04

CPC分类号： H04L47/30 ,  H04L47/10 ,  H04L47/11 ,  H04L47/263 ,  H04L49/3081 ,  H04Q11/0478 ,  H04L2012/5636

摘要： To control congestion in packet switching networks, control of the traffic sent by a given station to each of the downstream nodes to which it is directly connected is effected by control of the traffic that the upstream nodes to which it is directly connected are permitted to send to it. In this regard, a predictive model is used to predict the cross traffic, one round trip delay in advance that the given station can expect. The parameters for the predictive model are obtained by measurements in real time and by the use of moving averages. Using the predicted cross traffic, the amount of controlled traffic that the proximate downstream nodes can accommodate from the given node, and the correct state of the given node, the state of the given node one round trip delay into the future is predicted. This prediction is used to schedule the amount of traffic to be sent by each of its proximate upstream nodes.

摘要翻译： 为了控制分组交换网络中的拥塞，由给定站发送到其直接连接的每个下游节点的流量的控制通过对其直接连接的上游节点被允许发送的业务的控制来实现 给它 在这方面，预测模型用于预测交通流量，给定站预期的一次往返延迟。 预测模型的参数通过实时测量和移动平均值的使用获得。 使用预测的交叉业务，近似下游节点可以从给定节点容纳的受控业务量以及给定节点的正确状态，预测到给定节点的一个往返延迟的状态。 该预测用于调度其每个邻近的上游节点要发送的业务量。

公开(公告)号：US06618379B1

公开(公告)日：2003-09-09

申请号：US09206975

申请日：1998-12-08

申请人： Gopalakrishnan Ramamurthy ,  Ruixue Fan ,  Aleksandra Smiljanić

发明人： Gopalakrishnan Ramamurthy ,  Ruixue Fan ,  Aleksandra Smiljanić

IPC分类号： H04J300

CPC分类号： H04Q11/0478 ,  H04L49/101 ,  H04L49/1546 ,  H04L49/201 ,  H04L49/254 ,  H04L49/3018

摘要： A novel protocol for scheduling of packets in high-speed cell based switches is provided. The switch is assumed to use a logical cross-bar fabric with input buffers. The scheduler may be used in optical as well as electronic switches with terabit capacity. The proposed round-robin greedy scheduling (RRGS) achieves optimal scheduling at terabit throughput, using a pipeline technique. The pipeline approach avoids the need for internal speedup of the switching fabric to achieve high utilization. A method for determining a time slot in a N×N crossbar switch for a round robin greedy scheduling protocol, comprising N logical queues corresponding to N output ports, the input for the protocol being a state of all the input-output queues, output of the protocol being a schedule, the method comprising: choosing input corresponding to i=(constant-k−1)mod N, stopping if there are no more inputs, otherwise choosing the next input in a round robin fashion determined by i=(i+1)mod N; choosing an output j such that a pair (i,j) to a set C={(i,j)| there is at least one packet from I to j}, if the pair (i,j) exists; removing i from a set of inputs and repeating the steps if the pair (i,j) does not exist; removing i from the set of inputs and j from a set of outputs; and adding the pair (i,j) to the schedule and repeating the steps.

摘要翻译： 提供了一种用于在基于高速单元的交换机中调度分组的新颖协议。 假设交换机使用带输入缓冲区的逻辑交叉结构。 调度器可以用于具有太比特容量的光学以及电子开关中。 提出的循环贪心调度（RRGS）使用管道技术实现了吞吐量的最佳调度。 管道方式避免了交换结构的内部加速实现高利用率的需要。 一种用于确定用于轮询贪心调度协议的N×N交叉开关中的时隙的方法，包括对应于N个输出端口的N个逻辑队列，所述协议的输入是所有输入 - 输出队列的状态，协议的输出 作为调度，该方法包括：选择对应于i =（常数k-1）mod N的输入，如果不存在更多输入则停止，否则以由i =（i + 1）确定的循环方式选择下一个输入 ）mod N; 选择输出j使得对（i，j）与集合C = {（i，j）| 如果存在对（i，j），则存在从I到j}的至少一个分组; 从一组输入中删除i，如果对（i，j）不存在则重复步骤; 从输出集合中删除i，并从一组输出中删除j; 并将对（i，j）添加到时间表并重复步骤。

公开(公告)号：US06324165B1

公开(公告)日：2001-11-27

申请号：US08923978

申请日：1997-09-05

申请人： Ruixue Fan ,  Brian L. Mark ,  Gopalakrishnan Ramamurthy

发明人： Ruixue Fan ,  Brian L. Mark ,  Gopalakrishnan Ramamurthy

IPC分类号： H04L1226

CPC分类号： H04L12/5602 ,  H04L49/203 ,  H04L49/205 ,  H04L49/3018 ,  H04L49/3027 ,  H04L49/3081 ,  H04L49/503 ,  H04L2012/5636 ,  H04L2012/5651 ,  H04L2012/5679 ,  H04Q11/0478

摘要： A large capacity ATM core switch architecture is disclosed, which supports multiple traffic classes and quality-of-service (QoS) guarantees. The switch supports both real-time traffic classes with strict QoS requirements, e.g., CBR and VBR, and non-real-time traffic classes with less stringent requirements, e.g., ABR and UBR. The architecture also accommodates real-time and non-real-time multicast flows in an efficient manner. The switch consists of a high-speed core module that interconnects input/output modules with large buffers and intelligent scheduling/buffer management mechanisms. The scheduling can be implemented using a novel dynamic rate control, which controls internal congestion and achieves fair throughput performance among competing flows at switch bottlenecks. In the dynamic rate control scheme, flows are rate-controlled according to congestion information observed at bottleneck points within the switch. Each switch flow is guaranteed a minimum service rate plus a dynamic rate component which distributes any unused bandwidth in a fair manner.

摘要翻译： 公开了一种大容量ATM核心交换机架构，其支持多种业务类别和服务质量（QoS）保证。 交换机支持具有严格QoS要求的实时业务类别，例如CBR和VBR，以及具有不太严格要求的非实时业务类，例如ABR和UBR。 该架构还以有效的方式适应实时和非实时多播流。 该交换机由高速核心模块，可将输入/输出模块与大型缓冲区和智能调度/缓冲管理机制相互连接。 可以使用新颖的动态速率控制来实现调度，其控制内部拥塞并且在交换机瓶颈中的竞争流之间实现公平的吞吐量性能。 在动态速率控制方案中，根据在交换机内的瓶颈点观察到的拥塞信息，对流量进行速率控制。 每个交换机流被保证最小服务速率加上动态速率分量，以公平的方式分配任何未使用的带宽。

公开(公告)号：US06304551B1

公开(公告)日：2001-10-16

申请号：US08821864

申请日：1997-03-21

申请人： Gopalakrishnan Ramamurthy ,  Brian Lai-Bue Mark

发明人： Gopalakrishnan Ramamurthy ,  Brian Lai-Bue Mark

IPC分类号： H04J116

CPC分类号： H04Q11/0478 ,  H04L2012/563 ,  H04L2012/5637 ,  H04L2012/568

摘要： A scheme for determining the usage parameter control (UPC) values for an arbitrary traffic source from observations of its emitted cell stream is disclosed. The UPC values are used in a traffic shaping mechanism based on a dual leaky bucket, which shapes the cell stream by either discarding or delaying cells. The choice of UPC values is a function of the statistical characteristics of the observed cell stream; the user's tolerance for delay prior to the network access point; and the cost incurred on the network side. The chosen UPC values are then negotiated with the network. The source traffic characteristics may change dramatically over time, making the initially negotiated UPC descriptor inappropriate for the entire traffic stream. Hence, a method is disclosed for dynamically renegotiating UPC parameters whenever a predetermined change in traffic characteristics is detected. This method for real-time estimation and dynamic renegotiation of UPC parameters is the basis for a self-contained module which allows the source to make efficient use of the network resources.

摘要翻译： 公开了一种用于通过其发射的小区流的观察来确定任意业务源的使用参数控制（UPC）值的方案。 UPC值用于基于双漏斗的流量整形机制中，双重泄漏桶通过丢弃或延迟单元来形成单元流。 UPC值的选择是观察到的细胞流的统计特征的函数; 用户在网络接入点之前的延迟容限; 以及网络方面的成本。 然后，所选择的UPC值与网络协商。 源流量特征可能会随时间而急剧变化，从而最初协商的UPC描述符对于整个流量流是不合适的。 因此，每当检测到业务特性的预定变化时，公开了用于动态重新协商UPC参数的方法。 这种用于实时估计和UPC参数的动态重新协商的方法是允许源有效利用网络资源的自包含模块的基础。