Abstract: The invention includes a method and apparatus for providing load balancing of control traffic received by a mobility home agent implemented using multiple control elements. A method includes receiving, from a node, a control message intended for the network element, performing a load-balancing operation to select one of the control elements to handle the control message, and propagating the control message toward the selected one of the control elements. The load-balancing operation is performed using at least two load-balancing metrics comprising a first metric and a second metric. The load-balancing operation is performed in a manner for maintaining a context between the node from which the control message is received and the selected one of the control elements, such that subsequent control messages received from the node are propagated to the selected one of the control elements.

Abstract: The invention includes a method and apparatus for providing a distributed control plane for a mobility home agent by enabling multiple home addresses associated with multiple home agents to be assigned to a mobile node contemporaneously. A first home agent assigns a first home address to the mobile node. The first home agent propagates the first home address to the mobile node, which stores the first home address. The first home address is also propagated to a naming server and stored by the naming server for the mobile node. A second home agent, or the first home agent on behalf of the second home agent, assigns a second home address to the mobile node. The first home agent, or second home agent, propagates the second home address to the mobile node, which stores the second home address while continuing to store the first home address.

Abstract: The invention includes a method and apparatus for providing a distributed forwarding plane for a mobility home agent. The invention provides a method for controlling routing of packets for a mobile node in a network comprising a network domain including a plurality of forwarding elements being controlled by a control element. A method includes computing a route from one of the forwarding elements toward the mobile node and propagating the computed route toward that one of the forwarding elements. The route is computed using location information associated with the mobile node and routing information associated with the network domain.

Abstract: In one embodiment, a method for estimating the cardinality of one or more tags in a system that has the one or more tags and one or more readers. The reader issues a command requesting that the tags identify themselves. The command includes timing information defining a total number of timeslots. In response to the command, each of the one or more tags (i) selects a timeslot in which to reply to the command and (ii) issues a reply in the selected timeslot.

Abstract: In one embodiment, a method for estimating the number of tags in a set of tags in a system of tags and readers. The method includes, during each of a plurality of time intervals: (i) transmitting a command requesting that each tag that receives the command determine whether to transmit a reply; and (ii) receiving, in one or more timeslots of a frame corresponding to the time interval, replies from one or more tags. The method further includes providing an estimate of the number of tags in the set of one or more tags based on (i) timeslots in each of the plurality of time intervals that are zero timeslots, i.e., timeslots having no received reply, and (ii) the total number of timeslots in each frame.

Abstract: A method to provide authentication services to third party vendors by a service provider hosting an authentication, authorization and accounting (AAA) server or a similar device that can authenticate users for some other service. This method enables easy and substantially error-free end-user authentication, which forms the basis for enabling electronic transactions (e.g., web-based) that are less vulnerable to fraud.

Abstract: A method of characterizing a capacity region in a multi-channel, multi-radio mesh network of nodes interconnected by links. The method includes: (a) modeling the network by determining one or more link-flow feasibility constraints; (b) obtaining a feasible upper-capacity bound by solving an optimization problem using the one or more link-flow feasibility constraints as necessary conditions; and (c) using an algorithm adapted to provide a feasible lower-capacity bound by (i) receiving the solution to the optimization problem as input, (ii) allocating channels to links to meet a demand vector that satisfies the one or more link-flow feasibility constraints, and (iii) scheduling flows along the allocated channels. The upper- and lower-capacity bounds define the capacity region.

Abstract: A method of routing data from a source node to a destination node in a multi-hop network of nodes interconnected by links comprises: (a) determining that a link-flow vector satisfies one or more necessary scheduling conditions for achievability, wherein the link-flow vector represents a set of flows to be routed on one or more links from the source node to the destination node; (b) generating a scheduling multi-graph for the network, wherein the scheduling multi-graph comprises a graph having at least one pair of nodes with multiple edges therebetween; (c) deriving one or more sufficient scheduling conditions for achievability of the link-flow vector by edge-coloring the scheduling multi-graph; (d) solving a linear optimization problem over the one or more necessary scheduling conditions to obtain an upper bound on the achievability of the link-flow vector; (e) generating, based on the scheduling multi-graph, a solution comprising a set of routes and an associated schedule for achieving the link-flow vector,

Abstract: A dynamic binding protocol has three tasks that run in parallel: discovery, association, and operation. During discovery, control elements (CEs) and forwarding elements (FEs) learn about immediate neighbors and CEs in a SoftRouter network that has separate control and data planes. During association, FEs associate with CEs and are configured with basic parameters, such as IP interface addresses, hostnames, and the like. During operation, failover and packet tunneling between CEs and FEs is handled.

Abstract: The SoftRouter architecture separates the implementation of control plane functions from packet forwarding functions. In this architecture, all control plane functions are implemented on general purpose servers called the control elements (CEs) that may be multiple hops away from the forwarding elements (FEs). A network element (NE) or a router is formed using dynamic binding between the CEs and the FEs. There is a protocol failover mechanism for handling failovers initiated by FEs to transfer control from one CE to another CE.

Abstract: The SoftRouter architecture separates the implementation of control plane functions from packet forwarding functions. In this architecture, all control plane functions are implemented on general purpose servers called the control elements (CEs) that may be multiple hops away from the forwarding elements (FEs). A network element (NE) or a router is formed using dynamic binding between the CEs and the FEs. The flexibility of the SoftRouter architecture over conventional routers with collocated and tightly integrated control and forwarding functions results in increased reliability, increased scalability, increased security, ease of adding new functionality, and decreased cost.

Abstract: A SoftRouter architecture deconstructs routers by separating the control entities of a router from its forwarding components, enabling dynamic binding between them. In the SoftRouter architecture, control plane functions are aggregated and implemented on a few smart servers which control forwarding elements that are multiple network hops away. A dynamic binding protocol performs network-wide control plane failovers. Network stability is improved by aggregating and remotely hosting routing protocols, such as OSPF and BGP. This results in faster convergence, lower protocol messages processed, and fewer route changes following a failure. The SoftRouter architecture includes a few smart control entities that manage a large number of forwarding elements to provide greater support for network-wide control. In the SoftRouter architecture, routing protocols operate remotely at a control element and control one or more forwarding elements by downloading the forwarding tables, etc. into the forwarding elements.

Abstract: A system and method for identifying the source of a denial-of-service attack is described. In one implementation, flow information about packets transmitted through a network is collected at different points in the network. The flow level information is analyzed to reconstruct a path taken by a packet associated with a DoS attack to identify the source of such an attack.