Abstract: Systems and methods for routing packets by nodes in an ad hoc network in accordance with a link quality source routing protocol are disclosed. Route discovery, route maintenance, and metric maintenance are designed to propagate and keep current link quality measurements. Metric maintenance includes a reactive approach for links that a node is currently using to route packets, and a proactive mechanism for all links. Nodes are configured to include a send buffer, a maintenance buffer, a request table, link quality metric modules, and preferably a neighbor cache and a link cache. The invention allows for asymmetric links in the network. The invention may be implemented within a virtual protocol interlayer between the link and network layers. The invention may employ any particular link quality metrics, including metrics based on probing techniques as well as metrics based on knowledge gained in other ways.

Abstract: Disclosed is a virtual protocol “interlayer” between two protocol layers in a communications stack. When a communications task needs to be performed, but implementation within the existing protocol layers may hinder deployment due to issues of compatibility, the methods of the present invention are used to create an interlayer to handle the task. An addressing scheme peculiar to the interlayer is set up. The interlayer frees the other layers in the protocol stack to operate as before, leaving to the interlayer the specifics of performing the communications task. In one embodiment, an interlayer is built between the ISO/OSI protocol layers 2 and 3. Source routing is performed within this interlayer, using interlayer addresses. By using interlayer addresses rather than layer 2 or layer 3 addresses, this embodiment of source routing allows compatibility both with multiple layer 3 protocols and with multiple layer 2 network interfaces.

Abstract: A system and method for link quality routing uses a weighted cumulative expected transmission time path metric. A system for routing in a multi-hop ad hoc network, and a method for measuring the link quality of a route in the network, include assignment of a weight to a link in accordance with an expected transmission time of a packet over the link, and a combining of individual link weights for a route into a path metric. The path metric accounts for interference among links that use a shared channel. In the calculation of the path metric, the expected transmission times of links that interfere with one another are added, while the expected transmission times for non-interfering links are considered separately.

Abstract: Systems and methods for routing packets by nodes in an ad hoc network in accordance with a link quality source routing protocol are disclosed. Route discovery, route maintenance, and metric maintenance are designed to propagate and keep current link quality measurements. Metric maintenance includes a reactive approach for links that a node is currently using to route packets, and a proactive mechanism for all links. Nodes are configured to include a send buffer, a maintenance buffer, a request table, link quality metric modules, and preferably a neighbor cache and a link cache. The invention allows for asymmetric links in the network. The invention may be implemented within a virtual protocol interlayer between the link and network layers. The invention may employ any particular link quality metrics, including metrics based on probing techniques as well as metrics based on knowledge gained in other ways.

Abstract: A method and system that allows a client process to invoke a remote procedure. An operating system maintains a table with an entry for each remote procedure. Each entry of this table contains a signature that specifies a format in which parameters are exchanged between the client process and the remote procedure. When the client process requests the invocation of the remote procedure, the operating system creates a stack for the remote procedure. This stack is then mapped into the operating system's address space. By mapping the remote procedure's stack in this fashion, the operating system can simultaneously access the client's stack and the remote procedure's stack. The operating system then copies, in accordance with the remote procedure's signature, parameters directly from the client's stack to the remote procedure's stack. Once the parameters are copied, the remote procedure executes using the data contained on its own stack.