公开(公告)号：US20130003731A1

公开(公告)日：2013-01-03

申请号：US13611981

申请日：2012-09-12

申请人： Wenhu Lu ,  Alfred C. Lindem, III ,  Uma S. Chunduri

发明人： Wenhu Lu ,  Alfred C. Lindem, III ,  Uma S. Chunduri

IPC分类号： H04L12/28

CPC分类号： H04L45/02

摘要： Methods and apparatus for a network element to handle LSID collisions to prevent different LSAs associated with different routes from sharing the same LSID. According to one embodiment, responsive to determining that a tentative LSID that is generated for a first route that is being added collides with an LSID that is assigned to an LSA for a second route, and that one of the first and second routes is a host route, the host route is suppressed. If the first route is the host route, suppressing includes not originating an LSA for the first route. If the second route is the host route, suppressing includes purging the LSA for the second route and not originating an LSA for the second route. Although the host route is suppressed, network reachability of the range subsuming the host route is provided through the route that is not the host route.

摘要翻译： 用于处理LSID冲突的网元的方法和装置，以防止与不同路由相关联的不同LSA共享相同的LSID。 根据一个实施例，响应于确定为被添加的第一路由生成的临时LSID与分配给用于第二路由的LSA的LSID相冲突，并且所述第一和第二路由中的一个是主机 路由，主机路由被抑制。 如果第一条路由是主机路由，则抑制包括不发起第一条路由的LSA。 如果第二路由是主机路由，则抑制包括清除第二路由的LSA，而不是为第二路由发起LSA。 虽然主机路由被抑制，但是通过不是主机路由的路由来提供包含主机路由的范围的网络可达性。

公开(公告)号：US09014187B2

公开(公告)日：2015-04-21

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： H04L12/28 ,  H04L12/56 ,  H04L12/751 ,  H04L12/741

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。

公开(公告)号：US08717935B2

公开(公告)日：2014-05-06

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： H04L12/56 ,  H04L1/00 ,  H04L12/28 ,  H04Q7/24

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：US20130083692A1

公开(公告)日：2013-04-04

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 ,  H04L12/28

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：US20130073741A1

公开(公告)日：2013-03-21

申请号：US13310656

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： G06F15/16

CPC分类号： H04L45/12 ,  H04L45/28

摘要： A network element attempts to bring up an adjacency with a neighbor using a neighbor state machine (NSM) of an active OSPF instance, including: maintaining a neighbor data structure only in the active instance prior to the NSM transitioning to a Full state, delaying synchronization from the active instance to a standby OSPF instance of the neighbor data structure, maintaining tracking information of the NSM in only the active instance; installing LSAs received from the neighbor in both the LSDB of the active and standby instances, and, if and when the NSM of the active instance transitions to the Full state and all LSAs requested from the neighbor during database exchange are ensured to synchronize to the standby instance's LSDB, synchronizing from the active instance to the standby instance data item(s) of the neighbor data structure.

摘要翻译： 网元尝试使用活动OSPF实例的邻居状态机（NSM）与邻居建立邻接关系，包括：仅在NSM转换到完全状态之前，在活动实例中维护邻居数据结构，延迟同步 从活动实例到邻居数据结构的备用OSPF实例，仅在活动实例中维护NSM的跟踪信息; 在活动和备用实例的LSDB中安装从邻居收到的LSA，并且如果活动实例的NSM以及当数据库交换期间从邻居请求的所有LSA被保持同步到待机时， 实例的LSDB，从活动实例同步到邻居数据结构的备用实例数据项。

公开(公告)号：US20110044330A1

公开(公告)日：2011-02-24

申请号：US12544789

申请日：2009-08-20

申请人： Wenhu Lu ,  Alfred C. Lindem, III ,  Uma S. Chunduri

发明人： Wenhu Lu ,  Alfred C. Lindem, III ,  Uma S. Chunduri

IPC分类号： H04L12/56

CPC分类号： H04L45/02

摘要： Methods and apparatus for a network element to handle LSID collisions to prevent different LSAs associated with different routes from sharing the same LSID. According to one embodiment, responsive to determining that a tentative LSID that is generated for a first route that is being added collides with an LSID that is assigned to an LSA for a second route, and that one of the first and second routes is a host route, the host route is suppressed. If the first route is the host route, suppressing includes not originating an LSA for the first route. If the second route is the host route, suppressing includes purging the LSA for the second route and not originating an LSA for the second route. Although the host route is suppressed, network reachability of the range subsuming the host route is provided through the route that is not the host route.

摘要翻译： 用于处理LSID冲突的网元的方法和装置，以防止与不同路由相关联的不同LSA共享相同的LSID。 根据一个实施例，响应于确定为被添加的第一路由生成的临时LSID与分配给用于第二路由的LSA的LSID相冲突，并且所述第一和第二路由中的一个是主机 路由，主机路由被抑制。 如果第一条路由是主机路由，则抑制包括不发起第一条路由的LSA。 如果第二路由是主机路由，则抑制包括清除第二路由的LSA，而不是为第二路由发起LSA。 虽然主机路由被抑制，但是通过不是主机路由的路由来提供包含主机路由的范围的网络可达性。

公开(公告)号：US08681607B2

公开(公告)日：2014-03-25

申请号：US13457192

申请日：2012-04-26

申请人： Wenhu Lu ,  Sriganesh Kini

发明人： Wenhu Lu ,  Sriganesh Kini

IPC分类号： G01R31/08

CPC分类号： H04L45/42 ,  H04L45/00 ,  H04L45/02 ,  H04L45/123 ,  H04L45/1283 ,  H04L45/28 ,  H04L45/50

摘要： A network element implementing Multiprotocol Label Switching to automatically create an optimal deterministic back-up Label Switch Path (LSP) that is maximally disjointed from a primary LSP to provide a reliable back up to the primary LSP. The network element receives a request for a generation of an LSP, determines that the request for the generation of the LSP is for the back-up LSP, locates each link of the primary LSP in a traffic engineering database, modifies each link of the primary LSP to have a link cost significantly greater than an actual link cost to discourage use of each link of the primary LSP in the back-up LSP, executes a Constrained Shortest Path First algorithm to obtain the back-up LSP, wherein the back-up LSP has a maximum disjointedness from the primary LSP due to a modified cost of each link of the primary LSP, and returns the back-up LSP.

摘要翻译： 实现多协议标签交换的网元，自动创建一个最佳的确定性备份标签交换路径（LSP），最大限度地脱离主LSP，以提供可靠的备份到主LSP。 网元接收到生成LSP的请求，确定生成LSP的请求是用于备份LSP，将主LSP的每个链路定位在流量工程数据库中，修改主链路的每个链路 LSP具有明显大于实际链路成本的链路成本，以阻止在备用LSP中使用主LSP的每个链路，执行约束最短路径优先算法以获得备份LSP，其中备份LSP 由于主LSP的每个链路的修改成本，LSP与主LSP的最大不相容性，并返回备用LSP。

公开(公告)号：US08233387B2

公开(公告)日：2012-07-31

申请号：US12614323

申请日：2009-11-06

申请人： Wenhu Lu ,  Sriganesh Kini

发明人： Wenhu Lu ,  Sriganesh Kini

IPC分类号： G01R31/08

CPC分类号： H04L45/42 ,  H04L45/00 ,  H04L45/02 ,  H04L45/123 ,  H04L45/1283 ,  H04L45/28 ,  H04L45/50

摘要： A network element implementing Multiprotocol Label Switching to automatically create an optimal deterministic back-up Label Switch Path (LSP) that is maximally disjointed from a primary LSP to provide a reliable back up to the primary LSP. The network element receives a request for a generation of an LSP, determines that the request for the generation of the LSP is for the back-up LSP, locates each link of the primary LSP in a traffic engineering database, modifies each link of the primary LSP to have a link cost significantly greater than an actual link cost to discourage use of each link of the primary LSP in the back-up LSP, executes a Constrained Shortest Path First algorithm to obtain the back-up LSP, wherein the back-up LSP has a maximum disjointedness from the primary LSP due to a modified cost of each link of the primary LSP, and returns the back-up LSP.

摘要翻译： 实现多协议标签交换的网元，自动创建一个最佳的确定性备份标签交换路径（LSP），最大限度地脱离主LSP，以提供可靠的备份到主LSP。 网元接收到生成LSP的请求，确定生成LSP的请求是用于备份LSP，将主LSP的每个链路定位在流量工程数据库中，修改主链路的每个链路 LSP具有明显大于实际链路成本的链路成本，以阻止在备用LSP中使用主LSP的每个链路，执行约束最短路径优先算法以获得备份LSP，其中备份LSP 由于主LSP的每个链路的修改成本，LSP与主LSP的最大不相容性，并返回备用LSP。

公开(公告)号：US20120075986A1

公开(公告)日：2012-03-29

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： H04L12/26

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：US20110044348A1

公开(公告)日：2011-02-24

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

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，该网络单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。