Telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that ...

and

Computer networking A computer network is a set of computers sharing resources located on or provided by network nodes. The computers use common communication protocols over digital interconnections to communicate with each other. These interconnections are ...

, time-driven switching (TDS) is a node by node time variant implementation of

Circuit switching Circuit switching is a method of implementing a telecommunications network in which two network nodes establish a dedicated communications channel ( circuit) through the network before the nodes may communicate. The circuit guarantees the full ...

, where the propagating datagram is shorter in space than the distance between source and destination. With TDS it is no longer necessary to own a complete circuit between source and destination, but only the fraction of circuit where the propagating datagram is temporarily located. TDS adds flexibility and capacity to Circuit Switched networks but requires precise synchronization among nodes and propagating datagrams. Datagrams are formatted according to schedules that depend on

Quality of service Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a telephony or computer network, or a cloud computing service, particularly the performance seen by the users of the network. To quantitat ...

and availability of switching nodes and physical links. Respect to

the added time dimension introduces additional complexity to network management. Like

, TDS operates without buffers and header processing according to the

pipeline forwarding Pipeline forwarding (PF) applies to packet forwarding in computer networks the basic concept of '' pipelining'', which has been widely and successfully used in computing — specifically, in the architecture of all major central processing units (C ...

principle; therefore an all optical implementation with

Optical fibers An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass ( silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a mea ...

and

Optical Switches An optical transistor, also known as an optical switch or a light valve, is a device that switches or amplifies optical signals. Light occurring on an optical transistor's input changes the intensity of light emitted from the transistor's output wh ...

is possible with low cost. The TDS concept itself pervades and is applicable with advantage to existing data switching technologies, including

Packet switching In telecommunications, packet switching is a method of grouping data into '' packets'' that are transmitted over a digital network. Packets are made of a header and a payload. Data in the header is used by networking hardware to direct the p ...

, where packets, or sets of packets become the datagrams that are routed through the network. TDS has been invented in 2002 b
Prof. Mario Baldi
and prof.

Yoram Ofek Yoram Ofek (Hebrew: יורם אופק; September 25, 1950 – December 9, 2009) was a Marie Curie Chair and full professor in the Information Engineering and Computer Science Department at the University of Trento, Italy. He was the inventor of 45 ...

o
Synchrodyne Networks, Inc.
that is the assignee o

issued by both the

United States Patent and Trademark Office The United States Patent and Trademark Office (USPTO) is an agency in the U.S. Department of Commerce that serves as the national patent office and trademark registration authority for the United States. The USPTO's headquarters are in Alex ...

and the

European Patent Office The European Patent Office (EPO) is one of the two organs of the European Patent Organisation (EPOrg), the other being the Administrative Council. The EPO acts as executive body for the organisation

References

* M. Baldi, Y. Ofek,
Fractional Lambda Switching
" IEEE International Conference on Communications (ICC2002), Optical Networking Symposium, New York, NY, USA, Apr. 2002, pp. 2692-2696. * M. Baldi, Y. Ofek, "Fractional Lambda Switching - Principles of Operation and Performance Issues," SIMULATION: Transactions of The Society for Modeling and Simulation International, Vol. 80, No. 10, Oct. 2004, pp. 527-544 * WebLin

References

See also