公开(公告)号：US06507562B1

公开(公告)日：2003-01-14

申请号：US09336660

申请日：1999-06-18

申请人： Miriam C. Kadansky ,  Dah Ming Chiu ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

发明人： Miriam C. Kadansky ,  Dah Ming Chiu ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

IPC分类号： G06F1100

CPC分类号： H04L12/1877 ,  H04L12/185 ,  H04L12/1868

摘要： Receiver stations located close together in a computer network dynamically form a multicast repair tree by a plurality of receiver stations choosing a repair head station from among the closely located receiver stations. A receiver station calculates its distance from a repair head station by subtracting the decremented TTL value read from the IP header from the initial value of the TTL parameter carried in field TTL SCOPE of HELLO messages, transmitted by repair head stations. Using a criteria that a closer repair head station is a more optimum repair head station, receiver stations listen to each received HELLO message, calculate the distance to the repair head station, and reaffiliate with the closest repair head station.

摘要翻译： 位于计算机网络中的接收站由多个接收站动态地形成多播修复树，所述多个接收站从位于接近站的接收站中选择修复头站。 接收站通过从修复头站发送的HELLO消息的字段TTL SCOPE中携带的TTL参数的初始值中减去从IP报头读取的递减的TTL值来计算其与修复站的距离。 使用更接近的修理头站是更为优化的修复头站的标准，接收站收听每个接收到的HELLO消息，计算到维修站的距离，并且与最接近的维修站相连。

公开(公告)号：US06526022B1

公开(公告)日：2003-02-25

申请号：US09336670

申请日：1999-06-18

申请人： Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

发明人： Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

IPC分类号： G01R3108

CPC分类号： H04L12/1868 ,  H04L1/0002 ,  H04L1/1887 ,  H04L12/185 ,  H04L47/10 ,  H04L47/15 ,  H04L47/263 ,  H04L47/27 ,  H04L2001/0092

摘要： A method of detecting congestion in a computer network uses a receiving station which determines a first number of messages missing in a first acknowledgment window. The station then determines a second number of messages missing in a subsequent acknowledgement window. The station then measures congestion on the network in response to an increase in the number of missing messages as indicated by the first number of missing messages in the first acknowledgement window and the second number of missing messages in the second acknowledgement window.

摘要翻译： 一种在计算机网络中检测拥塞的方法使用确定在第一确认窗口中丢失的第一数量的消息的接收站。 然后，站确定后续确认窗口中丢失的第二个消息数。 该站然后响应于第一确认窗口中的第一数量的丢失消息和第二确认窗口中的第二数量的丢失消息所指示的丢失消息的数量的增加来测量网络上的拥塞。

公开(公告)号：US6104695A

公开(公告)日：2000-08-15

申请号：US52201

申请日：1998-03-31

申请人： Joseph S. Wesley ,  Radia J. Perlman ,  Stephen A. Hurst ,  Stephen R. Hanna ,  Miriam C. Kadansky ,  Philip M. Rosenzweig

发明人： Joseph S. Wesley ,  Radia J. Perlman ,  Stephen A. Hurst ,  Stephen R. Hanna ,  Miriam C. Kadansky ,  Philip M. Rosenzweig

IPC分类号： H04L12/18 ,  H04L12/701 ,  H04L12/761 ,  G01R31/08 ,  H04H1/00 ,  H04L12/66

CPC分类号： H04L45/00 ,  H04L12/1868 ,  H04L45/16

摘要： Determination of a Time To Live ("TTL") hop count for repair data units transmitted from a repair head to a standard destination device in a communications network is facilitated for multicast transmission. The repair head destination device monitors the path between the repair head destination device and the standard destination devices by exchanging messages with the respective standard destination devices. The repair head transmits control messages to each destination device including a dispatched TTL value and an Internet Protocol ("IP") TTL value. If the control message fails to reach one of the standard destination devices, that standard destination device transmits a transmission failure indication to the repair head destination device. In response to the transmission failure indication the TTL value employed for the control message is increased. Following receipt of the control message, the standard destination device calculates the TTL value required to transmit a data unit from the repair head to the standard destination device by subtracting the IP TTL value from the dispatched TTL value. If the calculated TTL difference value is non-zero then an excess-TTL indication is transmitted from the standard destination device to the repair head destination device.

摘要翻译： 确定通信网络中从维修头传送到标准目的地设备的修复数据单元的生存时间（“TTL”）跳数有利于组播传输。 修理头目的设备通过与相应的标准目的地设备交换消息来监视修复头目的地设备和标准目的地设备之间的路径。 修复头向每个目的地设备发送控制消息，包括调度的TTL值和互联网协议（“IP”）TTL值。 如果控制消息未能到达标准目的地设备之一，则该标准目的地设备向修复头目的设备发送传输失败指示。 响应于传输失败指示，增加了用于控制消息的TTL值。 在接收到控制消息之后，标准目的地设备通过从调度的TTL值减去IP TTL值来计算从修复头向标准目的地设备发送数据单元所需的TTL值。 如果计算的TTL差值为非零，则从标准目的地设备向维修头目的地设备发送过量TTL指示。

公开(公告)号：US06505253B1

公开(公告)日：2003-01-07

申请号：US09336659

申请日：1999-06-18

申请人： Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

发明人： Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Joseph S. Wesley ,  Philip M. Rosenzweig ,  Radia J. Perlman

IPC分类号： G06F1300

CPC分类号： H04L47/263 ,  H04L1/1832 ,  H04L12/185 ,  H04L12/1868 ,  H04L47/10 ,  H04L47/15 ,  H04L47/27 ,  H04L2001/0093

摘要： A multicast repair tree is established, the repair tree having one sender station and a plurality of repair head stations. A repair head station has an affiliated group of member stations. A repair head station retransmits a lost message to its affiliated group of member stations upon receipt from a member station of a NACK message indicating that the selected message was not received. Acknowledgment windows (ACK windows) are established in a member station for transmission of ACK or NACK message by the member station. A number of messages transmitted by the sender station during a transmission window is established. Also a same size of ACK window is established in the receiving stations, with a slot in the ACK window corresponding to each message transmitted by the repair head station. Each receiving station is assigned a slot in the ACK window during which time that receiving station transmits its ACK or NACK messages. Thus the ACK window slots assigned to receiver stations for transmission of ACK/NACK windows are staggered so that different receiver stations transmit their ACKNACK messages at different times. The slot for a particular receiver station to use may be assigned by a random process.

摘要翻译： 建立组播修复树，修复树具有一个发送站和多个修复头站。 修理站具有附属的成员站组。 修复头站在从成员站接收到表示所选择的消息未被接收的NACK消息的情况下向其附属成员组重发丢失的消息。 成员站建立确认窗口（ACK窗口），用于成员站发送ACK或NACK消息。 在发送窗口期间由发送站发送的多个消息被建立。 在接收站中建立相同大小的ACK窗口，ACK窗口中的时隙对应于由修复站发送的每个消息。 每个接收站在ACK窗口中被分配一个时隙，在该时间内接收站发送其ACK或NACK消息。 因此，分配给用于发送ACK / NACK窗口的接收机站的ACK窗口时隙交错，使得不同的接收机站在不同时间发送它们的ACKNACK消息。 用于要使用的特定接收机站的时隙可以通过随机过程来分配。

公开(公告)号：US06275859B1

公开(公告)日：2001-08-14

申请号：US09429192

申请日：1999-10-28

申请人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen A. Hurst ,  Radia J. Perlman ,  Joseph E. Provino ,  Philip M. Rosenzweig

发明人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Stephen A. Hurst ,  Radia J. Perlman ,  Joseph E. Provino ,  Philip M. Rosenzweig

IPC分类号： G06F1516

CPC分类号： H04L12/1877 ,  G06F15/16 ,  H04L9/321 ,  H04L9/3263 ,  H04L12/185 ,  H04L63/0823 ,  H04L63/104

摘要： To authenticate and authorize prospective members in a reliable multicast data distribution setup, the prospective members contact a central authority to obtain a “participation certificate” for the multicast session. The central authority authenticates each node and issues a digitally signed certificate to the node. Each certificate contains information specifying the manner in which the respective node is authorized to participate in the multicast session in addition to the respective node's public key. The nodes exchange their participation certificates with each other during session-establishment dialog to prove their identities and their authorization to participate. Each node verifies the rights of other nodes based on authorization information contained in the participation certificate received from the other node. Thus, a node is allowed to participate as a repair node only if it presents a participation certificate authorizing it to do so. Disruption in network operation is avoided by reducing the ability of malicious nodes to consume resources to the detriment of legitimate session members.

摘要翻译： 为了对可靠的组播数据分发设置中的潜在成员进行身份验证和授权，预期成员联系中央机构获取组播会话的“参与证书”。 中央机构对每个节点进行身份验证，并向节点发出数字签名的证书。 除了相应的节点的公共密钥之外，每个证书包含指定相应节点被授权参与多播会话的方式的信息。 节点在会话建立对话期间将他们的参与证书交给对方，以证明其身份和授权参与。 每个节点根据从其他节点接收到的参与证书中包含的授权信息来验证其他节点的权限。 因此，只有当一个节点呈现授权它的参与证书才可以作为修复节点参与。 通过降低恶意节点消耗资源的能力来避免网络运行中断，从而损害合法的会话成员。

公开(公告)号：US06658004B1

公开(公告)日：2003-12-02

申请号：US09473402

申请日：1999-12-28

申请人： Miriam C. Kadansky ,  Dah Ming Chiu ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Radia J. Perlman ,  Joseph S. Wesley

发明人： Miriam C. Kadansky ,  Dah Ming Chiu ,  Stephen R. Hanna ,  Stephen A. Hurst ,  Radia J. Perlman ,  Joseph S. Wesley

IPC分类号： H04L1228

CPC分类号： H04L12/1827 ,  H04L47/10 ,  H04L47/31 ,  H04L67/104 ,  H04L67/1063 ,  H04L67/1074 ,  H04L69/329

摘要： A method and apparatus for identifying a data message that is eligible for discard. A beacon node periodically transmits a beacon message to a plurality of client nodes communicatively coupled via a network. Each beacon message includes a beacon sequence number and preferably, the beacon sequence numbers are authenticated by the beacon, node. The client nodes, upon receipt of the beacon messages, verify the authenticity of the respective received beacon sequence numbers and generate a local sequence number derived from the received beacon sequence number. When one client in the session has data to transmit to another client in the session, the sending client assembles a data message and inserts its local sequence number in the data message prior to transmission of the data message to the other client nodes in the session. The client nodes receiving the data message discard the data message if their respective local sequence number at the time of receipt of the data message exceeds the local sequence number inserted in the data message by a predetermined value. In one embodiment, the beacon node generates sequence numbers at a periodic interval P but only transmits 1 out of every m beacon sequence numbers to the client nodes in the session. The client nodes each set a local sequence counter equal to the beacon sequence number upon receipt of the beacon message and thereafter, increment the local sequence counter periodically at interval P. The local sequence counter value is employed as the local sequence number in each client node.

摘要翻译： 一种用于识别符合丢弃资格的数据消息的方法和装置。 信标节点周期性地向经由网络通信耦合的多个客户端节点发送信标消息。 每个信标消息包括信标序列号，并且优选地，信标序列号由信标节点认证。 客户端节点在接收到信标消息后，验证相应接收到的信标序列号的真实性，并生成从接收到的信标序列号导出的本地序列号。 当会话中的一个客户端具有要在会话中传送给另一个客户端的数据时，发送客户端汇集一个数据消息，并将数据消息中的本地序列号插入到数据消息中，并传送到该会话中的其他客户机节点。 接收数据消息的客户节点如果在接收数据消息时其各自的本地序列号超过插入数据消息中的本地序列号预定值，则丢弃数据消息。 在一个实施例中，信标节点以周期性间隔P生成序列号，但是仅在每个m个信标序列号中发送1个到会话中的客户端节点。 客户端节点每接收到信标消息时都设置等于信标序列号的本地序列计数器，此后，以间隔P周期性地增加本地序列计数器。本地序列计数器值被用作每个客户端节点中的本地序列号 。

公开(公告)号：US06693907B1

公开(公告)日：2004-02-17

申请号：US09546946

申请日：2000-04-11

申请人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph E. Provino ,  Stephen R. Hanna

发明人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph E. Provino ,  Stephen R. Hanna

IPC分类号： H04L1228

CPC分类号： H04L12/1854 ,  H04L12/185 ,  H04L12/1868 ,  H04L47/10 ,  H04L47/11 ,  H04L47/15 ,  H04L47/263 ,  H04L47/27

摘要： A method and system for accurately measuring the reception characteristics of receivers in a multicast data distribution group having a sending node and a plurality of receivers. The multicast group is organized as a repair tree in which selected nodes of the multicast group comprise repair nodes for downstream receivers. Multicast data packets transmitted by the repair nodes include a retransmission count field in addition to the multicast packet header information, a session identifier, a packet sequence number and payload data. The retransmission count provides an indication of the number of times the respective packet has been retransmitted in response to a repair request. The receivers include an original packet counter and a retransmission count counter for each multicast session. Each receiver increments the original packet counter upon receipt of a packet that has not been previously received. Each receiver adds the value contained in the retransmission count field of a received packet to the retransmission count counter upon receipt of a retransmitted multicast packet that corresponds to a packet identified as a missing packet by the respective receiver. The data in the actual packet count counter and the retransmission count counter is employed to generate a loss metric at each receiver that provides a measure of the reception characteristic of the respective receiver for the particular multicast session.

摘要翻译： 一种用于在具有发送节点和多个接收机的组播数据分发组中精确地测量接收机的接收特性的方法和系统。 组播组被组织为修复树，其中多播组的选定节点包括下游接收机的修复节点。 由修复节点发送的组播数据分组除了组播分组头部信息，会话标识符，分组序列号和有效载荷数据之外还包括重传计数字段。 重传计数提供响应于修复请求重新发送相应分组的次数的指示。 接收机包括每个多播会话的原始分组计数器和重传计数计数器。 每个接收器在接收到先前未被接收到的分组时递增原始分组计数器。 每个接收者在接收到相应于由相应接收机识别为丢失分组的分组的重传的多播分组时，将接收分组的重传计数字段中包含的值添加到重传计数计数器。 采用实际分组计数计数器和重传计数计数器中的数据来在每个接收机处产生丢失度量，以提供针对特定多播会话的相应接收机的接收特性的测量。

公开(公告)号：US06269085B1

公开(公告)日：2001-07-31

申请号：US09497443

申请日：2000-02-03

申请人： Joseph E. Provino ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph S. Wesley

发明人： Joseph E. Provino ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph S. Wesley

IPC分类号： H04L1228

CPC分类号： H04L47/15 ,  H04L1/18 ,  H04L12/185 ,  H04L12/1877 ,  H04L12/56 ,  H04L47/12

摘要： A method and system for pruning slow multicast group members in a multicast group that includes a sending node and member nodes. The sending node and selected ones of the other nodes comprise repair heads of a repair tree. Each repair head has at least one child. Each of the member nodes generates a slowness metric. Each member node repair head aggregates its own slowness metric with the slowness metrics of their respective children in the tree along with a subtree flag that indicates whether the respective slowness metric is due to the reporting node or a node downstream of the reporting node. The member node repair heads propagates the largest of the aggregated slowness metrics upstream along with a subtree flag associated with the propagated slowness metric. Via this process the sending node receives the largest slowness metrics generated in respective branches of the repair tree along with corresponding subtree flags associated with the respective metrics. In response to the receipt of an indication of congestion at one or more of the member nodes when the sending node is transmitting at a minimum acceptable data rate, the sending node initiates pruning of slow group members in a predetermined manner. The globally largest slowness metric is employed in conjunction with the aggregated slowness metrics and associated subtree flags retained at the sending node and intermediate nodes to identify slow member nodes within the multicast group that should be pruned.

摘要翻译： 一种用于在包含发送节点和成员节点的组播组中修剪慢速组播组成员的方法和系统。 发送节点和其他节点中的所选节点包括修复树的修复头。 每个修理头至少有一个孩子。 每个成员节点生成一个慢度度量。 每个成员节点修复头将其自身的慢度度量与其各自的子节点在树中的慢度度量一起聚合，同时存在一个子树标志，该子树标志指示相应的慢度度量是否归因于报告节点或报告节点下游的节点。 成员节点修复头将最大的聚合慢度度量传播到与传播的慢度量度相关联的子树标志。 通过该过程，发送节点接收在修复树的相应分支中生成的最大的慢度度量以及与相应度量相关联的对应的子树标志。 响应于当发送节点以最小可接受数据速率进行发送时收到一个或多个成员节点的拥塞指示，发送节点以预定方式发起慢组成员的修剪。 全局最大慢度量度与聚集的慢度量度和保留在发送节点和中间节点处的相关子树标志结合使用，以识别应修剪的组播组内的慢成员节点。

公开(公告)号：US06850488B1

公开(公告)日：2005-02-01

申请号：US09549805

申请日：2000-04-14

申请人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph E. Provino

发明人： Joseph S. Wesley ,  Dah Ming Chiu ,  Miriam C. Kadansky ,  Joseph E. Provino

IPC分类号： G08C25/02 ,  H04L12/00 ,  H04L12/18 ,  H04L12/28 ,  H04L12/56

CPC分类号： H04L12/1881 ,  H04L47/10 ,  H04L47/263 ,  Y02D50/10

摘要： One embodiment of the present invention provides a system that facilitates efficient flow control for data transmissions between a sender and a plurality of receivers. The system operates by sending a stream of packets from the sender to the plurality of receivers, wherein the packets include information specifying a sampling window for the stream of packets. The sender subsequently receives feedback information from the plurality of receivers, wherein a receiver sends feedback information to the sender if a congestion condition occurs at the receiver while receiving packets within the sampling window. In response to the feedback information, the sender adjusts a rate of transmission for the stream of packets. In one embodiment of the present invention, the feedback information from the receivers is aggregated at intermediate nodes prior to reaching the sender in order to eliminate redundant feedback information. In one embodiment of the present invention, the sender communicates with the plurality of receivers through a tree of nodes, wherein the sender is a root node of the tree.

摘要翻译： 本发明的一个实施例提供了一种便于对发送器和多个接收器之间的数据传输的有效流控制的系统。 该系统通过从发送器向多个接收器发送分组流来操作，其中分组包括指定分组流的采样窗口的信息。 发送方随后从多个接收机接收反馈信息，其中如果接收机发生拥塞状况，则接收方在接收到采样窗口内的分组时发送反馈信息给发送方。 响应于反馈信息，发送者调整分组流的传输速率。 在本发明的一个实施例中，来自接收器的反馈信息在到达发送者之前在中间节点聚合，以消除冗余反馈信息。 在本发明的一个实施例中，发送者通过一个节点树与多个接收者进行通信，其中发送者是该树的根节点。