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：US08488444B2

公开(公告)日：2013-07-16

申请号：US11824885

申请日：2007-07-03

申请人： Clarence Filsfils ,  Stefano Previdi ,  David Ward

发明人： Clarence Filsfils ,  Stefano Previdi ,  David Ward

IPC分类号： G01R31/08

CPC分类号： H04L45/22 ,  H04L45/02 ,  H04L45/28 ,  H04L67/14 ,  H04L69/40

摘要： A method and system for failure notification at a remote node in communication with a local node are disclosed. The local node is configured for faster failure detection than the remote node. In one embodiment, the method includes establishing a failure monitoring session between the local node and the remote node, receiving at the remote node, a failure notification from the local node, the failure notification sent using a protocol of the failure monitoring session, and rerouting traffic at the remote node in response to the failure notification.

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：US20060126496A1

公开(公告)日：2006-06-15

申请号：US11010225

申请日：2004-12-10

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

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

IPC分类号： H04L12/26

CPC分类号： H04L45/28 ,  H04L45/02 ,  H04L45/04 ,  H04L45/22 ,  H04L45/50

摘要： A fast reroute (FRR) technique that may be deployed at the edge of a network having first and second edge devices coupled to a neighboring routing domain. If the first edge device detects a node or link failure that prevents it from communicating with the neighboring domain, the first edge device reroutes at least some data packets addressed to the neighboring domain to the second edge device. The second edge device receives the rerouted packets and then forwards the packets to the neighboring domain. Notably, the second edge device is not permitted to reroute the received packets a second time, e.g., upon identifying another inter-domain node or link failure. As such, loops are avoided at the edge of the network and packets are rerouted to the neighboring routing domain faster and more efficiently than in prior implementations.

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：US20070097974A1

公开(公告)日：2007-05-03

申请号：US11262061

申请日：2005-10-28

申请人： David Ward ,  John Scudder ,  Stefano Previdi ,  Clarence Filsfils ,  Robert Raszuk

发明人： David Ward ,  John Scudder ,  Stefano Previdi ,  Clarence Filsfils ,  Robert Raszuk

IPC分类号： H04L12/56 ,  H04J3/22 ,  H04L12/28 ,  H04J3/16

CPC分类号： H04L45/02 ,  H04L45/04 ,  H04L45/46

摘要： A packet data router comprises one or more first circuit boards comprising one or more first processors and first logic circuits programmed to perform packet data forwarding and packet data router control plane functions; and one or more second circuit boards comprising one or more second processors and second logic circuits programmed to perform only Border Gateway Protocol (BGP) route reflection server (RRS) functions. A distributed BGP route reflector system with the disclosed architecture distributes route reflection server software to a dedicated control board so that processing route reflection functions does not impact packet forwarding or protocol instances that converge forwarding tables.

摘要翻译： 分组数据路由器包括一个或多个第一电路板，包括一个或多个第一处理器和被编程为执行分组数据转发和分组数据路由器控制平面功能的第一逻辑电路; 以及一个或多个第二电路板，包括一个或多个第二处理器和第二逻辑电路，其被编程为仅执行边界网关协议（BGP）路由反射服务器（RRS）功能。 具有所公开架构的分布式BGP路由反射器系统将路由反射服务器软件分发到专用控制板，使得处理路由反射功能不会影响转发表的汇聚转发或协议实例。

公开(公告)号：US20070014293A1

公开(公告)日：2007-01-18

申请号：US11183381

申请日：2005-07-18

申请人： Clarence Filsfils ,  Stefano Previdi ,  John Scudder ,  David Ward

发明人： Clarence Filsfils ,  Stefano Previdi ,  John Scudder ,  David Ward

IPC分类号： H04L12/56

CPC分类号： H04L45/742 ,  H04L45/04 ,  H04L63/10

摘要： A method and system for protecting valuable resources within an autonomous system network. Address prefixes within the system are designated as valuable and a flag bit is associated with the address within routing tables of routers of the network. Interfaces to border routers are identified and when packets are received at those interfaces, the packets are flagged with a flag or tag bit. The destination address of the received packet is compared to the flag bit associated with the valuable resource prefix, and if the packet is directed to that resource the packet is dropped and/or logged, but the packet is not forwarded to that resource. In specific cases an interface from an external source may be configured to not create the flag or tag bit, wherein that packet will be delivered to the destination prefix of the packet.

摘要翻译： 一种用于保护自治系统网络内有价值资源的方法和系统。 系统中的地址前缀被指定为有价值的，并且标志位与网络的路由器的路由表中的地址相关联。 识别到边界路由器的接口，并且当在这些接口处接收到分组时，分组被标记为标志或标记位。 将接收到的分组的目的地地址与与有价值的资源前缀相关联的标志位进行比较，并且如果分组指向该资源，则分组被丢弃和/或记录，但是分组不被转发到该资源。 在特定情况下，来自外部源的接口可以被配置为不创建标志或标记位，其中该分组将被传递到分组的目的地前缀。

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。