Token ring

About: Token ring is a research topic. Over the lifetime, 1597 publications have been published within this topic receiving 23206 citations.

Local and Metropolitan Area Networks

Abstract: From the Publisher: Includes the full treatment of competing approaches of LAN and MAN technologies Details high-speed LANs: Gigabit Ethernet, 100-Mbps token ring, Fibre Channel, and ATM LANs Covers complete treatment of standards: IEEE 802 and ANSI standards, specifications from the ATM forum and the Fibre Channel Association, plus TCP/IP Presents structured cabling systems and cabling types Companion Web site at provides links to important sites, course support for instructors, as well as a link to the Computer Science Student Support Site maintained by the author

Authentication system based on periodic challenge/response protocol

Abstract: A wireless authentication system to control an operating state of a node being a computer, door control mechanism or any muti-state product based on the proximity of an authorized user to the node. The wireless authentication system comprises a security device implemented within the computer and a user authentication token ("token") in possession of the authorized user. A Challenge/Response protocol is configured between the security device and the token. The first successful Challenge/Response message exchange between the security device and the token places the node in an operational state allowing the authorized user access to the contents and/or networked resources of the node. Later Challenge/Response message exchanges are set to occur periodically to check whether the authorized user possessing the token has left the node unattended thereby causing the node to be placed in a non-operational state.

The Totem single-ring ordering and membership protocol

Abstract: Fault-tolerant distributed systems are becoming more important, but in existing systems, maintaining the consistency of replicated data is quite expensive. The Totem single-ring protocol supports consistent concurrent operations by placing a total order on broadcast messages. This total order is derived from the sequence number in a token that circulates around a logical ring imposed on a set of processors in a broadcast domain. The protocol handles reconfiguration of the system when processors fail and restart or when the network partitions and remerges. Extended virtual synchrony ensures that processors deliver messages and configuration changes to the application in a consistent, systemwide total order. An effective flow control mechanism enables the Totem single-ring protocol to achieve message-ordering rates significantly higher than the best prior total-ordering protocols.

Communication network integrating voice data and video with distributed call processing

Abstract: A token ring local area network integrates voice, data and image information over a single cable with voice packets having a higher priority than non-voice packets, and with all the voice packets having the same length and the maximum non-voice packet length being related to the voice packet length and to the maximum number of terminals in the network so as to ensure real-time voice reception Call processing functions are fully distributed among the voice terminals without the use of a centralized processing unit or a centralized data base Conference calls are effected by each party transmitting conference packets to a single destination party, with conference packets having a unique packet format wherein a single packet incorporates voice information from plural terminals so as to minimize the number of packets traversing the ring The token ring includes a plurality of interconnected stations or node coupling units, each of which is, in turn, connected to a plurality of nodes or terminals in a star-wired configuration, with each terminal having connected thereto one or more application devices, such as a digital feature telephone, a video camera, or a PC One or more of the node coupling units may be connected to a bridge for providing connection to another token ring, or to a gateway for providing connection to external networks, such as a PBX, a telephone central office, or a host computer

Broadcast protocols for distributed systems

Abstract: An innovative approach is presented to the design of fault-tolerant distributed systems that avoids the several rounds of message exchange required by current protocols for consensus agreement. The approach is based on broadcast communication over a local area network, such as an Ethernet or a token ring, and on two novel protocols, the Trans protocol, which provides efficient reliable broadcast communication, and the Total protocol, which with high probability promptly places a total order on messages and achieves distributed agreement even in the presence of fail-stop, omission, timing, and communication faults. Reliable distributed operations, such as locking, update, and commitment, typically require only a single broadcast message rather than the several tens of messages required by current algorithms. >