Fractional Lambda Switching
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Fractional Lambda Switching
Fractional lambda switching (FλS) leverages on time-driven switching (TDS) to realize sub-lambda switching in highly scalable dynamic optical networking, which requires minimum (possibly optical) buffers. Fractional lambda switching implies switching fractions of optical channels as opposed to whole lambda switching where whole optical channels are the switching unit. In this context, TDS has the same general objectives as optical burst switching and optical packet switching: realizing all-optical networks with high wavelength utilization. TDS operation is based on time frames (TFs) that can be viewed as virtual containers for multiple IP packets that are switched at every TDS switch based on and coordinated by the UTC (coordinated universal time) signal implementing pipeline forwarding. In the context of optical networks, synchronous virtual pipes SVPs typical of pipeline forwarding are called fractional lambda pipes (FλPs). In FλS, likewise in TDS, all packets in the same ...
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Time-driven Switching
In Telecommunication and Computer networking, time-driven switching (TDS) is a node by node time variant implementation of Circuit switching, 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 and availability of switching nodes and physical links. Respect to Circuit switching the added time dimension introduces additional complexity to network management. Like Circuit switching, TDS operates without buffers and header processing according to the pipeline forwarding principle; therefore an all optical implementation with Optical fibers and ...
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Optical Switching
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 while output power is supplied by an additional optical source. Since the input signal intensity may be weaker than that of the source, an optical transistor amplifies the optical signal. The device is the optical analog of the electronic transistor that forms the basis of modern electronic devices. Optical transistors provide a means to control light using only light and has applications in optical computing and fiber-optic communication networks. Such technology has the potential to exceed the speed of electronics, while conserving more power. Since photons inherently do not interact with each other, an optical transistor must employ an operating medium to mediate interactions. This is done without converting optical to electronic signa ...
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Optical Burst Switching
Optical burst switching (OBS) is an optical networking technique that allows dynamic sub-wavelength switching of data. OBS is viewed as a compromise between the yet unfeasible full optical packet switching (OPS) and the mostly static optical circuit switching (OCS). It differs from these paradigms because OBS control information is sent separately in a reserved optical channel and in advance of the data payload. These control signals can then be processed electronically to allow the timely setup of an optical light path to transport the soon-to-arrive payload. This is known as delayed reservation. Purpose The purpose of optical burst switching (OBS) is to dynamically provision sub-wavelength granularity by optimally combining electronics and optics. OBS considers sets of packets with similar properties called bursts. Therefore, OBS granularity is finer than optical circuit switching (OCS). OBS provides more bandwidth flexibility than wavelength routing but requires faster switching a ...
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Optical Packet Switching
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of optical instruments, instruments that use or Photodetector, detect it. Optics usually describes the behaviour of visible light, visible, ultraviolet, and infrared light. Because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for by using the Classical electromagnetism, classical electromagnetic description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of Ray (optics), rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of ...
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Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ...
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Coordinated Universal Time
Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of mean solar time (such as UT1) at 0° longitude (at the IERS Reference Meridian as the currently used prime meridian) and is not adjusted for daylight saving time. It is effectively a successor to Greenwich Mean Time (GMT). The coordination of time and frequency transmissions around the world began on 1 January 1960. UTC was first officially adopted as CCIR Recommendation 374, ''Standard-Frequency and Time-Signal Emissions'', in 1963, but the official abbreviation of UTC and the official English name of Coordinated Universal Time (along with the French equivalent) were not adopted until 1967. The system has been adjusted several times, including a brief period during which the time-coordination radio signals broadcast both UTC and "Stepped Atomic Time (SAT)" before a new UTC was adopted in 1970 and implemented in 1972. This change also a ...
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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 (CPUs) — and manufacturing — specifically in assembly lines of various industries starting from automotive to many others. Pipelining is known to be optimal independent of the specific instantiation. In particular, PF is optimal from various points of view: # ''High efficiency in utilization of network resources'', which enables accommodating a larger amount of traffic on the network, thus lowering operation cost and being the foundation for accommodating the exponential growth of modern networks. # ''Low implementation complexity'', which enables the realization of larger and more powerful networking systems at low cost, thus offering further support to network growth. # ''High scalability'', which is an immediate consequence of the abo ...
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Synchronous Virtual Pipe
When realizing pipeline forwarding a predefined schedule for forwarding a pre-allocated amount of bytes during one or more time frames along a path of subsequent switches establishes a synchronous virtual pipe (SVP). The SVP capacity is determined by the total number of bits allocated in every time cycle for the SVP. For example, for a 10 ms time cycle, if 20,000 bits are allocated during each of 2 time frames, the SVP capacity is 4 Mbit/s. Pipeline forwarding guarantees that reserved traffic, i.e., traveling on an SVP, experiences: # bounded end-to-end delay, # delay jitter lower than two TFs, and # no congestion and resulting losses. Two implementations of the pipeline forwarding were proposed: time-driven switching (TDS) and time-driven priority Time-driven priority (TDP) is a synchronous packet scheduling technique that implements UTC-based pipeline forwarding and can be combined with conventional IP routing to achieve the higher flexibility than another pipeline forwarding ...
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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 Alexandria, Virginia, after a 2005 move from the Crystal City area of neighboring Arlington, Virginia. The USPTO is "unique among federal agencies because it operates solely on fees collected by its users, and not on taxpayer dollars". Its "operating structure is like a business in that it receives requests for services—applications for patents and trademark registrations—and charges fees projected to cover the cost of performing the services tprovide . The Office is headed by the Under Secretary of Commerce for Intellectual Property and Director of the United States Patent and Trademark Office, a position last held by Andrei Iancu until he left office on January 20, 2021. Commissioner of Patents Drew Hirshfeld is performing the funct ...
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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 organisationGower's Report on Intellectual Property
, para 1.34
while the Administrative Council acts as its supervisory body as well as, to a limited extent, its legislative body. The actual legislative power to revise the lies with the Contracting States themselves when meeting at a Conference of the Contracting States. Within the European Patent Office,
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