Cisco Technology, Inc.

Russell Ivan White

Alvaro E Retana

Yi Yang

David Anthony Cook

James L Ng

Madhavi Wunnava Chandra

Donnie Van Savage

Thuan Van Tran

David Delano Ward

Keyur Patel

Ian Michael Charles Shand

Abhay Kumar Roy

Steven Edward Moore

Stanley M Ratliff

Liem Hong Nguyen

Alan Patrick Sheridan

Pascal Thubert

Rajiv Asati

Vincent Jean Ribiere

David A Cook

Thomas David Berry

Michael Barnes

Madhavi W Chandra

Brian Eliot Weis

Stewart Frederick Bryant

David N Cook

Sina Mirtorabi

Burjiz F Pithawala

Jimmy Philip Ervin

Timothy M Gage

Mosaddaq Hussain Turabi

Sanjeev Debdutta Rampal

Bruce Eric Pinsky

John E Cavanaugh

Mihail L Sichitiu

David Andrew Sacerdote

Alvaro Retano

Hoe Trinh

Alvaro Enrique Retana

One embodiment identifies all one-hop neighbor nodes and two-hop neighbor nodes of a node; determines an active set of one-hop neighbor nodes for the node, comprising: includes in the active set each one-hop neighbor node that is either an edge node or connected with at least one two-hop neighbor node with which no other one-hop neighbor nodes are connected; and if the active set is not yet complete, then: determine all combinations of one-hop neighbor nodes that are not already in the active set; and tests each combination in order of each combination's total-energy value to determine whether a specific combination is able to complete the active set; if no combination is able to complete the active set, then including all one-hop neighbor nodes in the active set; and communicates a message to each one-hop neighbor node in the active set indicating that it is in the active set.

Network topologies for energy efficient networks

In an example embodiment, a method and system is provided to determine and advertise a route advertisement in a reactive routing environment. In response to receiving a network address query with respect to a destination address at a routing device, an aggregate value, e.g. an address prefix, is determined and advertised in reply to the network address query. Determining of the aggregate value may comprise identifying within a range of network addresses represented by the aggregate value respective addresses for which the routing device does not have reachability information. The routing device may send address queries with respect to the identified addresses, to determine reachability via the routing device of those addresses. The aggregate value may be advertised conditional upon determining that a percentage of addresses within the corresponding range that can be reached via the routing device satisfies a predefined minimal coverage value.

Determining a route advertisement in a reactive routing environment

One embodiment receives at a first node in at least a portion of a network a routing table, the portion of the network comprising the first node and one or more second nodes, the routing table specifying the immediate neighbor that provides each of the best paths in the portion of the network based on a total cost; using the routing table, determines at the first node every second node that is necessary for the first node to reach all edges of the network, the second nodes that are necessary for the first node to reach all edges of the network comprising an active set for the first node; and sends a message from the first node to every second node to facilitate determining whether to shut down the second node.

In one embodiment, each node in a computer network determines a shortest looping ring back to the node through each of its neighbors. Each of these rings may then be marked in a particular direction, ensuring that any ring that shares a link with another ring is marked in such a way that the shared link is in the same direction in each of the rings that share the link. The links that are marked in the particular direction may be stored as part of a first topology. Conversely, the opposite direction on the links (e.g., bidirectional links or parallel unidirectional links) may be stored as a second topology that is link-disjoint from the first topology.

Creating balanced link-disjoint topologies in a computer network

In an embodiment, a method is provided at which it is used in a device. In this method, a logical identifier assigned to the device is identified and additionally, a mesh group identifier identifying a mesh group is identified. The logical identifier and the mesh group identifier are encoded in a routing message, which is used in an inter-domain routing protocol, and this routing message is transmitted to a reflector device in communication with the device. The reflector device is configured to transmit the routing message to a remote device included in the computer network.

Dynamic discovery mechanisms via inter-domain routing protocol

Techniques for sharing routing information over a network include determining whether the scale of a flooding domain exceeds a threshold. If so, then a router announcement message is sent over a particular link. The message indicates the local router is a flooding domain border router (FDBR). Summary routing information is determined with less than a certain level of detail used in the flooding domain for routers connected to the local router through links different from the particular link. The summary routing information is sent over the particular link in a link state message that includes type data that indicates summary routing information that crosses a FDBR. These techniques allow automatic favorable scaling of domains of shared routing information as the size of a mobile ad hoc network grows.

Method and apparatus for automatic sub-division of areas that flood routing information

In certain embodiments, performing a defensive procedure involves receiving at a first speaker of a first autonomous system a path advertisement from a second speaker of a second autonomous system. The path advertisement advertises a path from the second speaker of the second autonomous system. It is determined whether the second autonomous system is a stub autonomous system and whether a path length of the path is greater than one. If the second autonomous system is a stub and the path length is greater than one, a defensive measure is performed for the path. Otherwise, a default procedure is performed for the path.

Performing a defensive procedure in response to certain path advertisements

In an example embodiment, a method is provided. In this method, a network address query is received. A first network address of a known apparatus is retrieved from a routing table, in response to the network address query. A second network address may be determined based upon the network address query, the second network address having a smaller bit length than the first network address. An aggregate value may be advertised that represents a range of reachable network addresses, the range of reachable network addresses including the second network address.

Determining an optimal route advertisement in a reactive routing environment

Techniques are disclosed for synchronizing a database related to a first node in a network with multiple nodes. Each node includes a database different from a database on a different node. An inquiry control message is sent to each node in a candidate set of one or more nodes on the network, which are different from the first node. In response to the inquiry control message, the first node receives a first set of one or more messages from a particular node different from the first node. The first set indicates a portion from the database of the particular node. The portion is relevant for the first node. A particular portion of a first database for the first node is derived from the first set of messages. The particular portion is less than all of the first database. These techniques allow the first node to derive its full database from multiple adjacent nodes.

Synchronizing portions of a database with different databases on different nodes of a network

A method for communicating packets in a network environment is provided that includes receiving a packet at a network element and identifying a sequence number included in the packet that correlates to awareness information associated with one or more adjacent network elements. A table included in the network element may be updated in order to account for the awareness information included within the packet that has not been accounted for by the network element. In cases where the awareness information included in the packet has already been accounted for, the packet may be ignored.

System and method for exchanging awareness information in a network environment

The designated forwarding device functionality for forwarding of packets originated on a broadcast link among layer 2 is shared among multiple forwarding devices of different adjacency networks. As these networks do not form adjacencies, the forwarding devices do not natively participate in a same spanning tree for determining how to forward packets, and a designated forwarding device is used for forwarding packets originated on the common broadcast link. Distributing the role of a designated forwarding device among multiple of the forwarding devices provides a means for more efficiently forwarding packets to their destinations.

Partitioned forwarding of packets originated on a broadcast link among layer 2 forwarding devices of different adjacency networks

In one embodiment, a method includes receiving on a first communication link at a local router all routing information at a certain level of detail for each router of multiple routers communicating in a first flooding domain. A measure of distance is determined from a particular router in the first flooding domain to the local router. It is determined whether the measure of distance exceeds a threshold. If the measure of distance exceeds the threshold, then summary routing information with less than the certain level of detail is determined for the particular router. Also, certain routing information is sent over a different second communication link at the local router. The certain routing information includes the summary information for the particular router, and all routing information at the certain level of detail for a subset of routers communicating in the first flooding domain, which subset excludes the particular router.

Automatic overlapping areas that flood routing information

Growing community of inventors

Holly Springs, NC, United States of America

Russell Ivan White