Abstract: A method for a node in a network to determine an estimated diameter of a broadcast channel is disclosed. In particular embodiments, when a node receives a message from a neighbor computer, it can determine the received message's distance traveled and set that distance as an estimated diameter. It can then increment the distance traveled and forward the message to a neighbor computer. The node may be configured to set a new estimated diameter only if the new estimate is greater than the prior estimate. It may also be configured to send out a message broadcasting the new diameter estimate to its neighbors.

Abstract: A method of connecting to a network through a portal computer. A seeking computer dials the communications ports of a portal computer until it locates a call-in port. A port ordering algorithm is used to identify the call-in port. Communications ports selected by the port ordering algorithm may be re-ordered. The seeking computer uses the selected call-in port to request that the portal computer coordinate the connection of the seeking computer to the network.

Abstract: A technique for adding a participant to a network is provided. This technique allows for the simultaneous sharing of information among many participants in a network without the placement of a high overhead on the underlying communication network. To connect to the broadcast channel, a seeking computer first locates a computer that is fully connected to the broadcast channel. The seeking computer then establishes a connection with a number of the computers that are already connected to the broadcast channel. The technique for adding a participant to a network includes identifying a pair of participants that are connected to the network, disconnecting the participants of the identified pair from each other, and connecting each participant of the identified pair of participants to the added participant.

Abstract: A technique for broadcasting data across a network is provided. An originating participant sends data to another participant, which in turn sends the data that it receives from a neighbor participant to its other neighbor participants. Communication in the broadcast network is controlled by a contact module that locates the neighbor participants to which the seeking participant can be connected and by a join module that establishes the connection between the neighbor participants and the seeking participant. Data is numbered sequentially so that data that is received out of order can be queued and rearranged.

Abstract: A method for leaving a multicast computer network is disclosed. The method allows for the disconnection of a first computer from a second computer. When the first computer decides to disconnect from the second computer, the first computer sends a disconnect message to the second computer. Then, when the second computer receives the disconnect message from the first computer, the second computer broadcasts a connection port search message to find a third computer to which it can connect.

Abstract: A method for leaving a multicast computer network is disclosed. The method allows for the disconnection of a first computer from a second computer. When the first computer decides to disconnect from the second computer, the first computer sends a disconnect message to the second computer. Then, when the second computer receives the disconnect message from the first computer, the second computer broadcasts a connection port search message to find a third computer to which it can connect.

Abstract: A computer network for providing an information delivery service for a plurality of participants over the network is disclosed. Each participant has connections to at least three neighbor participants. An originating participant sends data to the other participants by sending the data through each of its connections to its neighbor participants. Further, each participant sends data that it receives from a neighbor participant to its other neighbor participants. The network is m-regular where m is the exact number of neighbor participants of each participant and the network is an incomplete graph.

Abstract: A broadcast technique in which a broadcast channel overlays a point-to-point communications network is provided. The broadcasting of a message over the broadcast channel is effectively a multicast to those computers of the network that are currently connected to the broadcast channel. In one embodiment, the broadcast technique provides a logical broadcast channel to which host computers through their executing processes can be connected. Each computer that is connected to the broadcast channel can broadcast messages onto and receive messages off of the broadcast channel. Each computer that is connected to the broadcast channel receives all messages that are broadcast while it is connected. The logical broadcast channel is implemented using an underlying network system (e.g., the Internet) that allows each computer connected to the underlying network system to send messages to each other connected computer using each computer's address.

Abstract: A method for processing data produced by a chemical sensor to predict a rate of diffusion and steady-state level of a chemical vapor absorbed by a coating applied to the chemical sensor. A chemical sensor (10) includes a surface acoustic wave device (12) in which a polymer coating (34) is provided to absorb a chemical vapor. As the vapor is absorbed by the polymer coating, a resonant frequency associated with the SAW device changes in proportion to the mass of the vapor absorbed. The change in resonant frequency is periodically sampled by a high-speed counter (58), digitized, and filtered by a microprocessor (100). In processing the filtered data, the microprocessor describes each data point as a constraint line in a (.tau.,C) space, where .tau. corresponds to the rate of diffusion of the chemical vapor into the polymer and C corresponds to the concentration of the chemical vapor in the polymer at a time t. A minimum energy function L(.tau.