A system and method for integrating an on-line service community with a foreign service (24) such as the Internet World Wide Web. An extension to a user's preferred Web browser (190) is manifested as a toolbar (196) comprised of control buttons and a viewer on a computer user's screen. By interacting with the control buttons of the toolbar (196) and the menus of the viewer, on-line service content (198) is delivered to the user in response to the URLs (22) specified by the user as he or she browses the Web. In addition, control buttons on the toolbar (196) present opportunities for interacting with other community members. Although the user may change URLs (22) and Web sites frequently, the present invention maintains a context for the user's interactions so that on-line service content (198) may be presented and interactions with other community members facilitated.

System for integrating an on-line service community with a foreign service

Method and apparatus providing connection-oriented services for packet switched data communications networks. Directory services include distributed discovery of MAC addresses and protocol alias addresses. Topology services include a link state topology exchange among switches, which provides each switch with a complete topology graph of the network. This enables an access switch receiving a data packet to determine a complete path from a source end system to a destination end system. Another service includes resolution of broadcast frames to unicast frames, in order to reduce the amount of broadcast traffic. Policy restrictions may be applied prior to connection setup. Path determination services enable multiple paths from a source to a destination. Connection management includes source routed mapping of connections on the desired path. A distributed call rerouting service is provided wherein if a link on an active path fails, each switch receives a topology change notification and unmaps any connection involving the failed link. A broadcast/unknown service provides restricted flooding of nonresolvable packets. Furthermore, connection-oriented switching is provided based on the source and destination MAC addresses as a connection identifier. Still further, resolution of networks outside the switch domain is enabled by access switches listening for network and server route advertisements and maintaining best routes to said networks and servers. The best route metrics may be combined with best path metrics to determine a path from a first access switch to an egress switch connected to the external network.

Distributed connection-oriented services for switched communication networks

This paper presents the concept, principles, and analysis of maximum ratio transmission for wireless communications where multiple antennas are used for both transmission and reception. The principles and analysis are applicable to general cases, including maximum ratio combining. Simulation results agree with the analysis. The analysis shows that the average overall SNR is proportional to the cross-correlation between channel vectors and that error probability decreases inversely with the (L/spl times/K)th power of the average SNR.

Maximum ratio transmission

An uplink common physical channel (random access channel) frame structure is disclosed with a separate preamble and data portion. The preamble is used by a base station to detect that a mobile station is attempting a random access request. The data portion of the channel includes user data, and pilot symbols that provide energy for channel estimation during reception of the data portion. A guard interval (TG) is preferably inserted between the preamble and data portion of the frame, which enables data detection to occur during an idle period. As such, the frame structures for both the common physical (random access) uplink channel and dedicated physical (traffic) uplink channel are compatible.

Random access in a mobile telecommunications system

In a system for interactively viewing videos, a selected video is transmitted as a plurality of frames of digitized video data for playback on a viewing device. The system receives the transmitted video data and includes a memory buffer for storing a segment of a selected one of the videos. The segment includes a predetermined number of frames representing a predetermined time interval of the selected video. In addition, the memory buffer including a write pointer and a read pointer. Software controlled servers are provided for witting and reading video data of the selected video to and from the memory buffer, independently, at locations indicated by the write and read pointers to transfer the selected video to the viewing device. By using a remote controller the viewer can position the read and write pointers to view any portion of the selected video interactively.

Video on demand with memory accessing and or like functions

In a self-healing network, virtual paths between user terminals are classified according to different fault recovery priority levels and communication links are mapped to virtual paths accommodated by the links and to bandwidths remaining in the respective links. Each priority level guarantees a fault recovery with a different amount of network resource. In response to a fault-indicating message identifying a failed virtual path, a search is made through the link-path table for an alternate virtual path and a remaining bandwidth of each link that comprises the alternate virtual path in descending order of the priority classes. In accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path that shares the same link with the alternate virtual path, a decision is made on whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the alternate virtual path from the remaining bandwidth. If the decision is affirmative, the alternate virtual path is established.

Communication network recoverable from link failure using prioritized recovery classes

In a high-speed packet multiplex communication network including a transmission line with a predetermined bandwidth and accommodating a plurality of information sources, the sources having various packet delivery rates over a range of between a peak rate and a lower rate than an average rate and demanding various transport performances, the sources are preliminarily classified into a plurality of types according to transport performances required and different transmission priorities are assigned to the different types, respectively. Bandwidths of sources of first priority and second priority are determined ones corresponding to the peak rate and the average rate, respectively. A virtual bandwidth may be calculated for the second priority source as a value between the peak and average rates. In response to connection requests from the sources, each of the connection requests is admitted when a bandwidth defined by the priority of each source is accepted in a residual bandwidth of the predetermined bandwidth, and the packets from the source of the first priority are preferentially transmitted to the transmission line, packets of the second priority source are transmitted when packets of the first priority source are absent. Thus, high bandwidth efficiency is insured while the high transport performance of the first priority source is maintained.

Call control with transmission priority in a packet communication network of an ATM type

Congestion control plays an important role in the effective and stable operation of ATM networks. This paper first gives a historical overview of rate-based congestion control algorithms developed in the ATM Forum, showing how the current ATM Forum standard regarding the traffic management control methods is exploited, by these algorithm. Then, analytical approach is used to quantitatively evaluate their performance and show the effectiveness of the rate-based approach. In presenting the numerical examples, we emphasize that appropriate control parameter settings are essential for proper traffic management in an ATM network environment.

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Rate-based congestion control for ATM networks

A network topology discovery method automatically recognizes the physical connection relationships of each ATM switch and each ATM terminal within an ATM network. Each ATM switch and ATM terminal mutually exchanges, by ILMI protocol, port identifiers that identify every ATM port of the ATM switch or ATM terminal as well as network addresses of network management agents that manage the ATM switch and the ATM terminal, to neighboring ATM switches and ATM terminals that are directly connected to its ports. Each ATM switch and ATM terminal stores tables for each of its ATM ports that include port identifiers which indicate the identities of connected ports as well as the network addresses of the network management agents that manage the neighboring ATM switches and ATM terminals. The ATM switches or ATM terminals automatically recognize the local connection relationships with its neighboring ATM switches or ATM terminals, using a network management system, by accessing connection information and then automatically recognizing the physical connection relationships of each ATM switch and each ATM terminal. The network management system recognizes the configuration within an ATM network, whether the network management system is inside or outside the ATM network, including when a router or existing LAN coexists with the ATM network. The identities of ports connected to each port are recognized, when a plurality of links exist between ATM switches, without requiring the assignment of a respective one of its ATM network management agents to each ATM switch. Interfaces between ATM switches as well as between an ATM switch and an ATM terminal are also automatically identified.

ATM network topology auto discovery method

In a packet-switched communications network, each of a plurality of terminals sequentially transmits control packets in response to a request for call before sequentially transmitting message packets. A switching node of the network is responsive to the control packets for establishing first and second logical channels through the network. Message packets are propagated through the first logical channel. The established logical channels are monitored to detect an abnormal condition. In the event of an abnormal condition in the first logical channel the message packets are re-routed to the second logical channel.

Hiroshi Suzuki

Papers

Communication network recoverable from link failure using prioritized recovery classes

Call control with transmission priority in a packet communication network of an ATM type

Rate-based congestion control for ATM networks

ATM network topology auto discovery method

Packet-switched communications network with parallel virtual circuits for re-routing message packets