Abstract: Methods are described for maintaining a small bounded aggregate state within network routers pertaining to selected architectural families. Small bounded reservations states are utilized wherein the method is fully scalable for use on large networks. The size of the aggregate state and the complexity of the associated refresh mechanism is determined by the parameters of the network, such as size, and classes, which is in contrast to states based on the number of end-user flows. The method can render deterministic bandwidth use within the network wherein real-time multimedia applications may be accorded strict delay and bandwidth guarantees. The invention provides a middle-ground between the stateful Intserv and the stateless SCORE architectures.

Abstract: A method for performing end-to-end “tree-based ordered multicasting” (TOM) which ensures collective integrity and consistency of distributed operations, and which is applicable to distributed multiparty collaboration and other multipoint applications. The TOM protocol performs cascaded total ordering of messages among on-tree hosts en route from senders to receivers, and does not require the building of a separate propagation graph to compute ordering information. TOM elects sequencer nodes dynamically based on address extensions of the multicast tree. Message ordering is performed by multicasting a message from each source node to receivers, unicasting a control message from a source node across a primary node to an ordering node for the designated multicast group or transmission in the tree, determining a binding sequence number for the message and a multicast to the receiver group, and delivering messages at end hosts according to the agreed-upon sequence numbers.

Abstract: Receiver-initiated collision avoidance methods for use in ad-hoc wireless networks in which carrier sensing is available. A number of protocol variants are described including RIMA-SP (simple polling), RIMA-DP (dual-purpose polling), and RIMA-BP (broadcast polling). These handshake methods according to the invention are capable of correctly avoiding collisions within a network that contains hidden nodes, and the RIMA-DP protocol provides higher performance levels than attainable with existing handshaking protocols within the ad-hoc wireless networks. The use of dual-purpose polling allows a control packet to be sent which has alternative functions, such as requesting data from the polled node, if available, and if not available then providing a transmission request from the polling node to send data to the polled node.

Abstract: A method is described for routing network traffic based on distance information to provide multiple paths that need not have equal costs. The routing algorithm MPATH of the present method provide loop-free routing at every instant, without the need of internodal synchronization which spans more than a single hop. Paths are computed using shortest distances and predecessor information in the routing computation. The use of multiple-successors allows for load-balancing within the network. The algorithm is both distributed and scalable to large networks due to its use of only one-hop synchronization. A number of procedures are described by way of example, including path computation, main table updating, neighbor table updating, and a multipath (MPATH) algorithm.

Abstract: A system and method of providing distributed election of a shared transmission schedule within an ad hoc network. The invention includes a collision-free access protocol which resolves channel access contentions for time division multiple access (TDMA) of a single channel. Time-slots are organized into part numbers, which are included within sections, a sequence of which define a block. Each node is given a ring number according to its location within the network topology and maintains local neighbor information along with its own part number and message digest. Collision-free channel access is automatically scheduled and repetitious contention phases are resolved by a random permutation algorithm operating in message digests. An empty time-slot utilization method is also described and data packets may also be transmitted subject to a non-zero collision probability within a blind section of the block.

Abstract: An efficient routing method (i.e., protocol) for use with wireless ad-hoc networks, referred to as “dynamic source tracing” or DST routing, that considerably reduces control overhead and thereby increases the available bandwidth while conserving power at the mobile stations. DST routing also provides high user throughput and can operate efficiently in a variety of traffic situations. DST employs a source-tracing algorithm that provides loop checking of complete paths prior to an entry being made into the routing table. In addition, DST makes use of information about the length and second-to-last hop (predecessor) of the shortest path to all known destinations, thus eliminating the counting to infinity problem, such as exhibited by the distributed Bellman-Ford protocol.

Abstract: An information object repository is configured to resolve a network layer anycast address to a network layer unicast address in response to a request for an information object at the network layer anycast address. The information object repository may be further configured to resolve the network layer anycast address by transmitting a request for the network layer unicast address and awaiting a response thereto, and, in some cases, to return a failure message to a source of the request for the information object if the response to the request for the network layer unicast address is not received within a timeout period. Preferably, the request for the network layer unicast address is a single IP packet that includes the network layer anycast address. Similarly, the request for the network layer unicast address is preferably a single IP packet that includes the network layer unicast address.

Abstract: A request for an information object at an address identified by a uniform resource locator (URL) is received; and the URL is mapped to a corresponding unicast address for the information object. Thereafter, the unicast address for the information object may be used as an anycast address.

Abstract: A request for an information object at an address identified by a uniform resource locator (URL) is received; and the URL is mapped to a corresponding anycast address for the information object. Thereafter, the anycast address for the information object may be resolved to a unicast address for the information object, and the information object sent to the client. The request may be received at an information object repository that is topologically closer to the client than any other information object repository. This closest information object repository may be selected according to specified performance metrics, such as: average delay from the selected information object repository to a source of the request, average processing delay at the selected information object repository, reliability of a path from the selected information object repository, available bandwidth in said path, and loads on the selected information object repository.

Abstract: An address of an information object repository that should service a client request for an information object is returned in response to a request therefor. The address of the information object repository which is returned is selected according to specified performance metrics regardless of whether or not the information object repository maintains a local copy of the information object that is the client request. In some cases, the address of the information object repository is further selected according to an address of a client making the client request. Further, the address of the information object repository is selected from a number of addresses of information object repositories.

Abstract: A method of providing multicast routing for use in ad hoc broadcast networks, such as wireless and mobile networks. The method is described within a protocol referred to as core-assisted mesh protocol, or CAMP. The method departs from traditional tree-structured multicast protocols and utilizes multicast meshes in which the network need not be flooded with control or data packets to establish routing paths. Each router configured for CAMP is capable of accepting unique packets arriving from any neighbor in the mesh, wherein packets are forwarded along reverse shortest paths to the receiver. Multiple cores may be defined for a group wherein the loss of a single core does not prevent packet flow. Routers for sender-only hosts are allowed to join the multicast mesh in simplex mode, and in certain cases may join without the sending of a join request.