公开(公告)号：US20060291391A1

公开(公告)日：2006-12-28

申请号：US11168694

申请日：2005-06-27

申请人： Jean-Philippe Vasseur ,  David Ward ,  Stefano Previdi ,  Clarence Filsfils

发明人： Jean-Philippe Vasseur ,  David Ward ,  Stefano Previdi ,  Clarence Filsfils

IPC分类号： H04J1/16 ,  H04L12/28 ,  H04L12/56

CPC分类号： H04L45/22 ,  H04L45/02 ,  H04L45/28 ,  H04L47/70 ,  H04L47/746 ,  H04L47/762 ,  H04L47/825 ,  H04L47/829

摘要： A technique dynamically resizes Traffic Engineering (TE) Label Switched Paths (LSPs) at a head-end node of the TE-LSPs in preparation to receive redirected traffic in response to an event in a computer network. The novel dynamic TE-LSP resizing technique is based on the detection of an event in the network that could cause traffic destined for one or more other (“remote”) head-end nodes of one or more TE-LSPs to be redirected to an event-detecting (“local”) head-end node of one or more TE-LSPs. An example of such a traffic redirection event is failure of a remote head-end node or failure of any of its TE-LSPs. Specifically, the local head-end node maintains TE-LSP steady state sampling and resizing frequencies to adapt the bandwidth of its TE-LSP(s) to gradual changes in the network over time. Upon detection of an event identifying possible traffic redirection, the local head-end node enters a Fast Resize (FR) state, in which the sampling and resizing frequencies are increased to quickly adapt the TE-LSP bandwidth(s) to any received redirected traffic.

摘要翻译： 技术动态地调整TE-LSP的头端节点处的流量工程（TE）标签交换路径（LSP），准备响应于计算机网络中的事件接收重定向的流量。 新型动态TE-LSP调整大小技术基于网络中可能导致一个或多个TE-LSP的一个或多个其他（“远程”）头端节点的流量被重定向到的事件的检测 一个或多个TE-LSP的事件检测（“本地”）头端节点。 这种流量重定向事件的示例是远程头端节点的故障或其任何TE-LSP的故障。 具体来说，本地前端节点维护TE-LSP稳态采样和调整频率，以适应其TE-LSP的带宽随时间逐渐变化的网络。 在检测到识别可能的业务重定向的事件时，本地前端节点进入快速调整大小（FR）状态，其中增加采样和调整大小频率以快速地将TE-LSP带宽适配到任何接收到的重定向业务 。

公开(公告)号：US20060193248A1

公开(公告)日：2006-08-31

申请号：US11068081

申请日：2005-02-28

申请人： Clarence Filsfils ,  David Ward ,  Stefano Previdi ,  Jean-Philippe Vasseur ,  Jim Guichard ,  Robert Raszuk

发明人： Clarence Filsfils ,  David Ward ,  Stefano Previdi ,  Jean-Philippe Vasseur ,  Jim Guichard ,  Robert Raszuk

IPC分类号： H04J3/14 ,  H04L12/56 ,  H04J1/16 ,  H04L12/28

CPC分类号： H04L45/18 ,  H04L45/04 ,  H04L45/22 ,  H04L45/28 ,  H04L45/50

摘要： A local fast reroute (FRR) technique is implemented at the edge of a computer network. In accordance with the technique, if an edge device detects a node or link failure that prevents it from communicating with a neighboring routing domain, the edge device reroutes at least some data packets addressed to that domain to a backup edge device which, in turn, forwards the packets to the neighboring domain. The rerouted packets are designated as being “protected” (i.e., rerouted) data packets before they are forwarded to the backup edge device. The backup edge device identifies protected data packets as those which contain a predetermined “service” label in their MPLS label stacks. In other words, the service label is used as an identifier for packets that have been FRR rerouted. Upon receiving a data packet containing a service label, the backup edge device is not permitted to reroute the packet a second time, e.g., in response to another inter-domain node or link failure, thereby preventing loops from developing at the edge of the network.

摘要翻译： 本地快速重路由（FRR）技术在计算机网络的边缘实现。 根据该技术，如果边缘设备检测到阻止其与相邻路由域通信的节点或链路故障，则边缘设备将至少一些寻址到该域的数据分组重新路由到备用边缘设备， 将数据包转发到相邻域。 重新路由的数据包在被转发到备份边缘设备之前被指定为“保护”（即重新路由）数据分组。 备份边缘设备将受保护的数据包标识为在其MPLS标签堆栈中包含预定“服务”标签的数据包。 换句话说，服务标签被用作已被FRR重新路由的数据包的标识符。 在接收到包含服务标签的数据分组时，不允许备份边缘设备第二次重新路由该分组，例如响应于另一个域间节点或链路故障，从而防止在网络边缘发展的环路 。

公开(公告)号：US20060045024A1

公开(公告)日：2006-03-02

申请号：US10928866

申请日：2004-08-27

申请人： Stefano Previdi ,  Clarence Filsfils ,  David Ward

发明人： Stefano Previdi ,  Clarence Filsfils ,  David Ward

IPC分类号： H04L12/56 ,  H04L12/26

CPC分类号： H04L45/56 ,  H04L45/02 ,  H04L45/12 ,  H04L47/24 ,  H04L47/6235 ,  H04L49/90 ,  H04L49/9078

摘要： A technique enables an intermediate network node to efficiently process link-state packets using a single running context (i.e., process or thread). The intermediate network node floods received link-state packets (LSP) before performing shortest path first (SPF) calculations and routing information base (RIB) updates. In addition, the node limits the number of LSPs that are permitted to be flooded before the node performs its SPF calculations. More specifically, if the number of link-state packets that are flooded during a flooding cycle exceeds a first predetermined threshold value, the node performs the SPF calculations before additional packets may be flooded. The intermediate network node also limits how long its RIB update may be delayed in favor of flooding operations. When the number of LSPs flooded after the SPF calculations exceeds a second predetermined threshold value or there are no more packets to be flooded, the node updates the contents of its RIB based on the SPF calculations.

公开(公告)号：US20050111349A1

公开(公告)日：2005-05-26

申请号：US10719003

申请日：2003-11-21

申请人： Jean Vasseur ,  Stefano Previdi ,  Clarence Filsfils ,  David Ward

发明人： Jean Vasseur ,  Stefano Previdi ,  Clarence Filsfils ,  David Ward

IPC分类号： G01S13/00 ,  H04B20060101 ,  H04B1/00 ,  H04B1/40 ,  H04B1/69 ,  H04L5/04 ,  H04L12/28 ,  H04L12/56 ,  H04M1/00 ,  H04W88/06 ,  H04W88/10 ,  H04L12/26

CPC分类号： H04L45/12 ,  H04B1/71635 ,  H04L45/02 ,  H04L45/18 ,  H04L45/22 ,  H04L45/28 ,  H04L45/46 ,  H04L45/48 ,  H04L45/50 ,  H04W88/06 ,  H04W88/10

摘要： A method and apparatus are disclosed for performing a shortest path first network routing path determination in a data communications network based in part on information about links that are associated as shared risk link groups. Micro-loops are avoided in computing shortest path first trees by considering whether links are within shared risk link groups. In a first approach, for each link state packet in a link state database, listed adjacencies are removed if the link between the node originating the LSP and the reported adjacency belongs to a shared risk link group for which one component (local link) is known as down, and a shortest path first computation is then performed. In a second approach, during the SPT computation and after having added a first node to a path, each neighboring node is added to a tentative tree if and only if, a link between the first node and the neighboring node does not belong to a shared risk link group for which one component (local link) is known as down.

摘要翻译： 公开了一种用于在数据通信网络中执行最短路径第一网络路由路径确定的方法和装置，部分地基于关于作为共享风险链路组关联的链路的信息。 通过考虑链路是否在共享风险链路组内，避免了计算最短路径树的微循环。 在第一种方法中，对于链路状态数据库中的每个链路状态分组，如果发起LSP的节点和报告的邻接关系之间的链路属于已知一个组件（本地链路）的共享风险链路组，则删除列出的邻接关系 然后执行最短路径优先计算。 在第二种方法中，在SPT计算期间，并且在将第一节点添加到路径之后，当且仅当第一节点和相邻节点之间的链路不属于共享时，每个相邻节点被添加到暂定树 一个组件（本地链路）被称为down的风险链路组。

公开(公告)号：US09143431B2

公开(公告)日：2015-09-22

申请号：US12981444

申请日：2010-12-29

申请人： Pradosh Mohapatra ,  Stefano B. Previdi ,  Clarence Filsfils ,  David Ward

发明人： Pradosh Mohapatra ,  Stefano B. Previdi ,  Clarence Filsfils ,  David Ward

IPC分类号： H04L12/28 ,  H04L12/751

CPC分类号： H04L45/025

摘要： Hiding a service node in a network from a network topology is provided. In one embodiment, for example, an apparatus for hiding a service node in a network from a network topology, the apparatus comprising: a network interface; a processor; and one or more stored sequences of instructions which, when executed by the processor, cause the processor to perform: discovering a service node in a data network in accordance with a link-state protocol wherein the service node provides a network topology dependent service other than packet forwarding; establishing a link-state adjacency with the service node and one or more packet forwarding nodes in accordance with the link-state protocol; receiving a link-state advertisement; in response to identifying the link-state advertisement as an originating link-state advertisement sent from the service node, suppressing flooding of the received link-state advertisement to the one or more packet forwarding nodes.

摘要翻译： 提供了从网络拓扑中隐藏网络中的服务节点。 在一个实施例中，例如，一种用于从网络拓扑中隐藏网络中的服务节点的装置，所述装置包括：网络接口; 处理器 以及一个或多个存储的指令序列，当由所述处理器执行时，所述指令序列使所述处理器执行：根据链路状态协议在数据网络中发现服务节点，其中所述服务节点提供除 分组转发; 根据链路状态协议与服务节点和一个或多个分组转发节点建立链路状态邻接; 接收链接状态广告; 响应于将所述链路状态广告识别为从所述服务节点发送的始发链路状态广告，抑制所接收的链路状态广告对所述一个或多个分组转发节点的洪泛。

公开(公告)号：US20060126495A1

公开(公告)日：2006-06-15

申请号：US11001149

申请日：2004-12-01

申请人： James Guichard ,  Jean-Philippe Vasseur ,  Thomas Nadeau ,  Clarence Filsfils ,  David Ward ,  Stefano Previdi

发明人： James Guichard ,  Jean-Philippe Vasseur ,  Thomas Nadeau ,  Clarence Filsfils ,  David Ward ,  Stefano Previdi

IPC分类号： H04J1/16

CPC分类号： H04L45/22 ,  H04L41/0677 ,  H04L43/50 ,  H04L45/02 ,  H04L45/28

摘要： A path verification protocol (PVP) which enumerates a series of messages sent to a set of nodes, or routers, along a suspected path identifies forwarding plane problems for effecting changes at the control plane level. The messages include a command requesting interrogation of a further remote node for obtaining information about the path between the node receiving the PVP message and the further remote node. The node receiving the PVP message replies with a command response indicative of the outcome of attempts to reach the further remote node. The series of messages collectively covers a set of important routing points along a path from the originator to the recipient. The aggregate command responses to the series of PVP messages is analyzed to identify not only whether the entire path is operational, but also the location and nature of the problem.

公开(公告)号：US07428213B2

公开(公告)日：2008-09-23

申请号：US10719003

申请日：2003-11-21

申请人： Jean Philippe Vasseur ,  Stefano B. Previdi ,  Clarence Filsfils ,  David Ward

发明人： Jean Philippe Vasseur ,  Stefano B. Previdi ,  Clarence Filsfils ,  David Ward

IPC分类号： H04L12/26

CPC分类号： H04L45/12 ,  H04B1/71635 ,  H04L45/02 ,  H04L45/18 ,  H04L45/22 ,  H04L45/28 ,  H04L45/46 ,  H04L45/48 ,  H04L45/50 ,  H04W88/06 ,  H04W88/10

摘要： A method and apparatus are disclosed for performing a shortest path first network routing path determination in a data communications network based in part on information about links that are associated as shared risk link groups. Micro-loops are avoided in computing shortest path first trees by considering whether links are within shared risk link groups. In a first approach, for each link state packet in a link state database, listed adjacencies are removed if the link between the node originating the LSP and the reported adjacency belongs to a shared risk link group for which one component (local link) is known as down, and a shortest path first computation is then performed. In a second approach, during the SPT computation and after having added a first node to a path, each neighboring node is added to a tentative tree if and only if, a link between the first node and the neighboring node does not belong to a shared risk link group for which one component (local link) is known as down.

摘要翻译： 公开了一种用于在数据通信网络中执行最短路径第一网络路由路径确定的方法和装置，部分地基于关于作为共享风险链路组关联的链路的信息。 通过考虑链路是否在共享风险链路组内，避免了计算最短路径树的微循环。 在第一种方法中，对于链路状态数据库中的每个链路状态分组，如果发起LSP的节点和报告的邻接关系之间的链路属于已知一个组件（本地链路）的共享风险链路组，则删除列出的邻接关系 然后执行最短路径优先计算。 在第二种方法中，在SPT计算期间，并且在将第一节点添加到路径之后，当且仅当第一节点和相邻节点之间的链路不属于共享时，每个相邻节点被添加到暂定树 一个组件（本地链路）被称为down的风险链路组。

公开(公告)号：US20070180105A1

公开(公告)日：2007-08-02

申请号：US11343051

申请日：2006-01-30

申请人： Clarence Filsfils ,  David Ward

发明人： Clarence Filsfils ,  David Ward

IPC分类号： G06F15/173

CPC分类号： H04L45/00 ,  H04L12/40 ,  H04L12/413 ,  H04L41/069 ,  H04L41/12 ,  H04L43/00 ,  H04L45/28

摘要： A technique distinguishes between link and node failure using bidirectional forwarding detection (BFD) in a computer network. According to the novel technique, a BFD session is established over a first link between a monitoring node and a first interface of a monitored node. In addition, one or more novel unidirectional BFD (uBFD) sessions from one or more corresponding other interfaces of the monitored node to the monitoring node (e.g., as configured by the monitored node to detect its failure), the one or more uBFD sessions traversing links other than the first link (e.g., “not-via” the monitored node) are established, the one or more uBFD sessions traversing links other than the first link (e.g., “not-via” the monitored node). For instance, the one or more uBFD sessions correspond to one or more line cards of the monitored node. In response to detecting a lack of connectivity resulting from, e.g., failure of the BFD session, the monitoring node determines that the first link has failed if at least one uBFD session is operational. Moreover, in response to detecting failure of the BFD session and all of the one or more uBFD sessions, the monitoring node determines that the monitored node has failed.

摘要翻译： 一种技术在计算机网络中使用双向转发检测（BFD）来区分链路和节点故障。 根据这种新技术，在被监控节点的监控节点和第一个接口之间的第一个链路上建立BFD会话。 另外，一个或多个新的单向BFD（uBFD）会话从受监视节点的一个或多个对应的其他接口到监视节点（例如，由监视节点配置以检测其故障），一个或多个uBFD会话遍历 建立除第一链路之外的其他链路（例如，“未通过”的被监视节点），一个或多个遍历第一链路以外的链路的uBFD会话（例如，“不通过被监控节点”）。 例如，一个或多个uBFD会话对应于被监视节点的一个或多个线路卡。 响应于检测到由于例如BFD会话的故障而导致的连接的缺乏，如果至少一个uBFD会话可操作，则监视节点确定第一链路已经失败。 此外，响应于检测到BFD会话和所有一个或多个uBFD会话的故障，监视节点确定被监控节点已经失败。

公开(公告)号：US20070180104A1

公开(公告)日：2007-08-02

申请号：US11342446

申请日：2006-01-30

申请人： Clarence Filsfils ,  David Ward

发明人： Clarence Filsfils ,  David Ward

IPC分类号： G06F15/173 ,  G06F15/16

CPC分类号： H04L45/22 ,  H04L45/02 ,  H04L45/04 ,  H04L45/28

摘要： A technique enables bidirectional forwarding detection (BFD) between first and second edge devices in a computer network, wherein the second edge device is not configured for BFD. According to the novel technique, a BFD Echo session is established from the first edge device to the first edge device via the second edge device, i.e., along a monitored path (e.g., a single link). Also, an external border gateway protocol (eBGP) session is established between the first and second edge devices over an alternate path (e.g., an eBGP multi-hop session). The first edge device determines that the monitored path is down upon not receiving a returned BFD Echo message from the second edge device. In response, the first edge device notifies the second edge device that the monitored path is down through the eBGP session over the alternate path. Notably, upon notifying the second edge device that the monitored path is down, the first edge device breaks the eBGP session, and upon receiving the notification, the second edge device also breaks the eBGP session.

摘要翻译： 一种技术在计算机网络中的第一和第二边缘设备之间实现双向转发检测（BFD），其中第二边缘设备不配置用于BFD。 根据该新技术，经由第二边缘设备，即沿着被监视的路径（例如，单个链路），从第一边缘设备到第一边缘设备建立BFD回波会话。 另外，通过备用路径（例如，eBGP多跳会话）在第一和第二边缘设备之间建立外部边界网关协议（eBGP）会话。 第一边缘设备确定在没有从第二边缘设备接收到返回的BFD Echo消息时，所监视的路径下降。 作为响应，第一边缘设备通过备用路径通过eBGP会话通知第二边缘设备所监视的路径正在关闭。 值得注意的是，当通知第二边缘设备被监控的路径关闭时，第一边缘设备破坏eBGP会话，并且在接收到该通知时，第二边缘设备也中断eBGP会话。

公开(公告)号：US20060165013A1

公开(公告)日：2006-07-27

申请号：US11045015

申请日：2005-01-26

申请人： Stefano Previdi ,  Clarence Filsfils ,  Jean-Philippe Vasseur ,  Benoit Claise ,  David Ward

发明人： Stefano Previdi ,  Clarence Filsfils ,  Jean-Philippe Vasseur ,  Benoit Claise ,  David Ward

IPC分类号： H04L12/28

CPC分类号： H04L45/02

摘要： A method of identifying an egress point to a network location in a data communications network comprising a plurality of nodes and links there between comprises the step, performed at the identifying node, of receiving a notification through the network advertising an adjacency to a network location. The method further comprises the steps, performed at the identifying node, of deriving from the notification adjacency information and identifying, from the adjacency information, the egress point.

摘要翻译： 一种识别包括在其中的多个节点和链路的数据通信网络中的网络位置的出口点的方法包括：在识别节点执行的步骤，通过网络接收通知与网络位置相邻的通知。 所述方法还包括在所述识别节点处执行的从所述通知邻接信息导出并从所述邻接信息识别所述出口点的步骤。