公开(公告)号：US20130083801A1

公开(公告)日：2013-04-04

申请号：US13349392

申请日：2012-01-12

申请人： Wenhu Lu ,  Ing-Wher Chen ,  Alfred C. Lindem, III

发明人： Wenhu Lu ,  Ing-Wher Chen ,  Alfred C. Lindem, III

IPC分类号： H04L12/28 ,  H04L12/56

CPC分类号： H04L45/28 ,  H04L45/22 ,  H04L45/58 ,  H04L45/60

摘要： A network element is configured to reduce the synchronization costs for implementing Open Shortest Path First (OSPF) Nonstop routing (NSR). The reduced synchronization costs are achieved by reducing the number of acknowledgement messages that are needed to be sent though reliable inter-process communication (IPC) between the active OSPF instance and the standby OSPF instance. The number of acknowledgement messages is reduced by tracking the link state advertisements (LSAs) that have been sent by the active OSPF instance to the standby OSPF instance and by the standby OSPF replying with an acknowledgement of only the last LSA in a group of LSAs received from the active OSPF instance, where the group can have a variety of boundaries such as a group of LSAs in an IPC message. This avoids having a significant number of acknowledgement messages sent through the IPC.

摘要翻译： 网元被配置为减少实现开放最短路径优先（OSPF）不间断路由（NSR）的同步成本。 降低的同步成本是通过减少在活动的OSPF实例和备用OSPF实例之间通过可靠的进程间通信（IPC）需要发送的确认消息的数量来实现的。 通过跟踪已经由主动OSPF实例发送到备用OSPF实例的链路状态通告（LSA），以及通过仅接收所接收到的一组LSA中最后一个LSA的确认的备用OSPF来回复确认消息的数量 来自活动的OSPF实例，其中组可以具有各种边界，例如IPC消息中的一组LSA。 这避免了通过IPC发送大量确认消息。

公开(公告)号：US20130070637A1

公开(公告)日：2013-03-21

申请号：US13310653

申请日：2011-12-02

申请人： Alfred C. Lindem, III ,  Wenhu Lu ,  Ing-Wher Chen

发明人： Alfred C. Lindem, III ,  Wenhu Lu ,  Ing-Wher Chen

IPC分类号： H04L12/28

CPC分类号： H04L45/12 ,  H04L45/32

摘要： A network element is configured for open shortest path first (OSPF) non-stop routing (NSR) with reliable flooding. An active OSPF instance determines to flood a link-state advertisement (LSA). The LSA is synchronized with a backup OSPF instance including storing the LSA with a status that indicates that flooding is pending. The active OSPF instance attempts to reliably flood the LSA to a set of adjacent network elements of the flooding scope of the LSA. If flooding of the LSA completes, the active OSPF instance causes the backup OSPF instance to alter the status of the LSA to indicate that flooding is complete. If the backup OSPF instance becomes the currently active OSPF instance prior to the flooding of the LSA completing, then the new active OSPF instance attempts to reliably flood the LSA.

摘要翻译： 网络元素配置为具有可靠淹没的开放最短路径优先（OSPF）不间断路由（NSR）。 活动的OSPF实例决定了洪泛链路状态广告（LSA）。 LSA与备份OSPF实例同步，包括存储LSA，状态指示洪泛等待处理。 活动的OSPF实例尝试将LSA可靠地泛洪到LSA的泛洪范围的一组相邻网元。 如果LSA的泛洪完成，则活动的OSPF实例会使备份OSPF实例改变LSA的状态，表示洪泛完成。 如果备份OSPF实例在LSA完成洪泛之前成为当前活动的OSPF实例，则新的活动OSPF实例会尝试可靠地洪泛LSA。

公开(公告)号：US07990877B2

公开(公告)日：2011-08-02

申请号：US12121601

申请日：2008-05-15

申请人： Wenhu Lu

发明人： Wenhu Lu

IPC分类号： H04L12/26

CPC分类号： H04L41/12 ,  H04L45/12 ,  H04L45/122 ,  H04L45/125 ,  H04L45/20 ,  H04L45/42 ,  H04L45/50

摘要： A method and apparatus for performing a dynamically runtime adjustable constrained shortest path first (CSPF) computation of a label switched path (LSP) is described. In one embodiment of the invention, a network element acting as a source of the LSP receives a request to compute the LSP which includes one or more traffic engineering constraints. If the request includes at least one additive constraint, the network element performs a CSPF calculation. If the request does not include an additive constraint, the network element prunes each link that does not satisfy each of the constraints, and prunes those links whose paths converge at an intermediary network element according to cost, calculates a path to the destination according to cost. Other methods and apparatuses are also described.

摘要翻译： 描述了用于执行标签交换路径（LSP）的动态运行时可调约束最短路径优先（CSPF）计算的方法和装置。 在本发明的一个实施例中，充当LSP的源的网络元件接收包括一个或多个业务工程约束的计算LSP的请求。 如果请求包括至少一个附加约束，则网元执行CSPF计算。 如果请求不包含加性约束，则网络元素修剪不满足每个约束条件的每个链路，并根据成本修剪其路由在中间网元收敛的链路，根据成本计算到目的地的路径 。 还描述了其它方法和装置。

公开(公告)号：US08923312B2

公开(公告)日：2014-12-30

申请号：US13345508

申请日：2012-01-06

申请人： Ing-Wher Chen ,  Wenhu Lu ,  Alfred C. Lindem, III

发明人： Ing-Wher Chen ,  Wenhu Lu ,  Alfred C. Lindem, III

IPC分类号： H04L12/56 ,  H04L12/703 ,  H04L12/755 ,  H04L12/775 ,  H04L12/773 ,  H04B7/212 ,  H04L12/707

CPC分类号： H04L45/28 ,  H04L45/021 ,  H04L45/22 ,  H04L45/58 ,  H04L45/60

摘要： A network element is configured for synchronizing dynamic OSPF data between an active OSPF instance and a backup OSPF instance. Upon an OSPF data synchronization event, the active OSPF instance synchronizes dynamic OSPF data with the backup OSPF instance. Upon receiving the dynamic OSPF data, the backup OSPF instance determines whether the requisite data structures exist. If the data structures do not exist, the backup OSPF instance returns a NACK to the active OSPF instance and clears its dynamic OSPF data. Responsive to receiving the NACK, the active OSPF instance resynchronizes its dynamic OSPF data with the backup OSPF instance.

摘要翻译： 网元配置为在活动的OSPF实例和备份OSPF实例之间同步动态OSPF数据。 在OSPF数据同步事件中，活动OSPF实例将动态OSPF数据与备份OSPF实例同步。 备份OSPF实例在接收到动态OSPF数据后，确定是否存在必需的数据结构。 如果数据结构不存在，则备份OSPF实例将向活动OSPF实例返回NACK，并清除其动态OSPF数据。 响应于接收到NACK，活动OSPF实例将其动态OSPF数据与备份OSPF实例重新同步。

公开(公告)号：US08830867B2

公开(公告)日：2014-09-09

申请号：US13277100

申请日：2011-10-19

申请人： Wenhu Lu ,  Albert J. Tian

发明人： Wenhu Lu ,  Albert J. Tian

IPC分类号： H04L12/28 ,  H04L12/757

CPC分类号： H04L45/023

摘要： A method, performed by a transmitter network element utilizing a link state routing protocol which has a maximum link state message size. The method is for providing information to avoid a disruption in data forwarding that would result from a receiver network element performing preferred route computations based on an incomplete set of link state messages. The method includes generating a complete set of link state messages having information indicating that the link state messages are the complete set of the link state messages. The complete set of the link state messages are collectively coherent with a link state of the transmitter network element. The method also includes transmitting the complete set of the link state messages, and the information indicating that the link state messages are the complete set of the link state messages, to a network. Also disclosed are transmitter network elements, receiver network elements, and methods thereof.

摘要翻译： 一种由发射机网元利用具有最大链路状态消息大小的链路状态路由协议执行的方法。 该方法用于提供信息以避免由于接收机网络元件基于不完整的链路状态消息集执行优选路由计算而导致的数据转发中断。 该方法包括生成具有指示链路状态消息是链路状态消息的完整集合的信息的完整链路状态消息集合。 链路状态消息的完整集合与发射机网络元件的链路状态集体一致。 该方法还包括向网络发送完整的链路状态消息集合，以及指示链路状态消息是链路状态消息的完整集合的信息。 还公开了发射机网元，接收机网元及其方法。

公开(公告)号：US08804489B2

公开(公告)日：2014-08-12

申请号：US13091081

申请日：2011-04-20

申请人： Wenhu Lu ,  Albert Jining Tian

发明人： Wenhu Lu ,  Albert Jining Tian

IPC分类号： H04L12/26 ,  H04L12/56 ,  H04L12/24

CPC分类号： H04L41/0659 ,  H04L41/0654 ,  H04L45/02 ,  H04L45/16 ,  H04L45/28 ,  H04L45/32 ,  H04L45/48 ,  H04L45/66

摘要： A router detects a network failure and responsive to that failure, floods a fast failure notification message out a set of interfaces of the router. The fast failure notification message includes information that identifies the network failure and includes as its source MAC (Media Access Control) address a MAC address that is assigned to an interface that is coupled with the detected network failure and is not part of the set of interfaces of the router. The router updates a routing table to reflect the network failure. The flooding of the fast failure notification message is performed prior to completion of the routing table update to reflect the network failure.

摘要翻译： 路由器检测到网络故障并响应该故障，将快速故障通知消息洪泛出路由器的一组接口。 快速故障通知消息包括识别网络故障的信息，并且包括作为其源MAC（媒体访问控制）地址的MAC地址，该MAC地址被分配给与检测到的网络故障相耦合的接口，并且不是该接口集合的一部分 的路由器。 路由器更新路由表以反映网络故障。 在完成路由表更新之前执行快速故障通知消息的泛滥以反映网络故障。

公开(公告)号：US08681823B2

公开(公告)日：2014-03-25

申请号：US13356517

申请日：2012-01-23

申请人： Sriganesh Kini ,  Wenhu Lu

发明人： Sriganesh Kini ,  Wenhu Lu

IPC分类号： H04J3/06 ,  H04L12/56 ,  H04L12/28

CPC分类号： H04L45/507 ,  H04J3/0635 ,  H04L45/02 ,  H04L45/023 ,  H04L45/16 ,  H04L45/22 ,  H04L45/28 ,  H04L45/50

摘要： A network element that has a broadcast interface to a broadcast network becoming operational determines whether at least one alternate path exists to the broadcast network. The broadcast interface is to carry traffic on a label switched path. If an alternate path exists, the broadcast interface will not be advertised to the broadcast network until label distribution protocol (LDP) is operational with all neighbors on the broadcast interface.

摘要翻译： 具有到广播网络的广播接口变得可操作的网络元件确定是否存在至少一个替代路径到广播网络。 广播接口是在标签交换路径上携带流量。 如果存在备用路径，广播接口将不会广播到广播网络，直到标签分发协议（LDP）与广播接口上的所有邻居一起运行。

公开(公告)号：US08630162B2

公开(公告)日：2014-01-14

申请号：US12983126

申请日：2010-12-31

申请人： Wenhu Lu ,  Albert Jining Tian ,  Sriganesh Kini

发明人： Wenhu Lu ,  Albert Jining Tian ,  Sriganesh Kini

IPC分类号： G01R31/08

CPC分类号： H04L45/22 ,  H04L45/02 ,  H04L45/28 ,  H04L45/50 ,  H04L45/66

摘要： Fast flooding based fast convergence to recover from a network failure. A router detects a network failure, and responsive to that failure, transmits a fast failure notification message to a set of one or more routers. The fast failure notification message includes information that identifies the network failure and also indicates that the fast failure notification message is to be flooded by the set of routers independently of convergence. The router updates a routing table to reflect the network failure. The transmission of the fast failure notification message is performed prior to completion of the routing table update to reflect the network failure.

摘要翻译： 快速洪泛快速收敛，从网络故障中恢复。 路由器检测到网络故障，并响应于该故障，将快速故障通知消息发送到一个或多个路由器的集合。 快速故障通知消息包括识别网络故障的信息，并且还指示快速故障通知消息将被该组路由器独占于收敛而泛洪。 路由器更新路由表以反映网络故障。 在完成路由表更新之前执行快速故障通知消息的传输以反映网络故障。

公开(公告)号：US08477795B2

公开(公告)日：2013-07-02

申请号：US12546433

申请日：2009-08-24

申请人： Sriganesh Kini ,  Wenhu Lu

发明人： Sriganesh Kini ,  Wenhu Lu

IPC分类号： H04L12/56 ,  H04L29/02

CPC分类号： H04L45/16 ,  H04L45/02 ,  H04L45/021 ,  H04L45/507 ,  H04L2463/143

摘要： A method and apparatus for LDP-IGP synchronization for broadcast networks. In one embodiment of the invention, responsive to a network element bringing up an adjacency with a Designated Router of the broadcast network on a broadcast interface, that network element advertises in its Link State Advertisement (LSA) a peer-to-peer (P2P) adjacency to each member of the broadcast network that has bidirectional IGP communication with the network element instead of advertising a pseudo-node adjacency to the pseudo-node of the broadcast network. Each P2P adjacency includes a high cost to discourage use of those links for transit traffic. After LDP becomes operational with all neighbors on the broadcast interface, the network element advertises the pseudo-node adjacency instead of the P2P adjacencies. Accordingly, transit traffic is avoided through that network element until LDP is operational with all neighbors on the broadcast interface.

摘要翻译： 用于广播网络的LDP-IGP同步的方法和装置。 在本发明的一个实施例中，响应于在广播接口上与广播网络的指定路由器相邻的网络元件，该网元在其链路状态通告（LSA）中通告对等（P2P） 与广播网络的与网络单元进行双向IGP通信的每个成员相邻，而不是向广播网络的伪节点广告伪节点邻接。 每个P2P邻接包括高昂的成本，以阻止使用这些链路进行过境业务。 LDP与广播接口上的所有邻居操作后，网元发布伪节点邻接而不是P2P邻接。 因此，通过该网络元件避免转接流量，直到LDP与广播接口上的所有邻居一起运行。

公开(公告)号：US20120147888A1

公开(公告)日：2012-06-14

申请号：US12966895

申请日：2010-12-13

申请人： Wenhu Lu ,  Alfred C. Lindem, III

发明人： Wenhu Lu ,  Alfred C. Lindem, III

IPC分类号： H04L12/56

CPC分类号： H04L45/02 ,  H04L45/54

摘要： A network element of a communications network includes a fresh route queue, a stale route queue, a Routing Information Base (RIB), a network interface, and a routing protocol module. The network interface receives link state information from other network elements. The routing protocol module determines a plurality of routes from the link state information. The routing protocol module identifies among the plurality of routes a subset of routes that are present in the stale route queue, adds the subset of routes to the fresh route queue, and deletes the subset of routes from the stale route queue. The routing protocol module then remove routes in the RIB that correspond to any routes remaining in the stale route queue, and moves the routes from the fresh route queue to the stale route queue. Related methods for managing routes in a RIB of a network element are disclosed.

摘要翻译： 通信网络的网元包括新路由队列，陈旧路由队列，路由信息库（RIB），网络接口和路由协议模块。 网络接口从其他网元接收链路状态信息。 路由协议模块从链路状态信息确定多条路由。 路由协议模块在多个路由中标识出现在过时路由队列中的路由的子集，将路由子集添加到新路由队列，并从陈旧的路由队列中删除路由子集。 路由协议模块然后删除RIB中与残留在过时路由队列中的任何路由相对应的路由，并将路由从新鲜路由队列移动到陈旧的路由队列。 公开了一种用于管理网元的RIB中的路由的相关方法。