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Traffic Policing (communications)
In communications, traffic policing is the process of monitoring network traffic for compliance with a traffic contract and taking steps to enforce that contract. Traffic sources which are aware of a traffic contract may apply traffic shaping to ensure their output stays within the contract and is thus not discarded. Traffic exceeding a traffic contract may be discarded immediately, marked as non-compliant, or left as-is, depending on administrative policy and the characteristics of the excess traffic. Effects The recipient of traffic that has been ''policed'' will observe packet loss distributed throughout periods when incoming traffic exceeded the contract. If the source does not limit its sending rate (for example, through a feedback mechanism), this will continue, and may appear to the recipient as if link errors or some other disruption is causing random packet loss. The received traffic, which has experienced policing en route, will typically comply with the contract, alt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asynchronous Transfer Mode
Asynchronous Transfer Mode (ATM) is a telecommunications standard defined by American National Standards Institute (ANSI) and ITU-T (formerly CCITT) for digital transmission of multiple types of traffic. ATM was developed to meet the needs of the Broadband Integrated Services Digital Network as defined in the late 1980s, and designed to integrate telecommunication networks. It can handle both traditional high-throughput data traffic and real-time, low-latency content such as telephony (voice) and video.ATM Forum, The User Network Interface (UNI), v. 3.1, , Prentice Hall PTR, 1995, page 2. ATM provides functionality that uses features of circuit switching and packet switching networks by using asynchronous time-division multiplexing.McDysan (1999), p. 287. In the OSI reference model data link layer (layer 2), the basic transfer units are called '' frames''. In ATM these frames are of a fixed length (53 octets) called ''cells''. This differs from approaches such as Internet P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voice Over IP
Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the Internet, rather than via the public switched telephone network (PSTN), also known as plain old telephone service (POTS). Overview The steps and principles involved in originating VoIP telephone calls are similar to traditional digital telephony and involve signaling, channel setup, digitization of the analog voice signals, and encoding. Instead of being transmitted over a circuit-switched network, the digital information is packetized and transmission occurs as IP packets over a packet-switched network. They transport media streams using special media delivery protoc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connection Admission Control
Connection may refer to: Mathematics * Connection (algebraic framework) *Connection (mathematics), a way of specifying a derivative of a geometrical object along a vector field on a manifold * Connection (affine bundle) * Connection (composite bundle) *Connection (fibred manifold) *Connection (principal bundle), gives the derivative of a section of a principal bundle * Connection (vector bundle), differentiates a section of a vector bundle along a vector field *Cartan connection, achieved by identifying tangent spaces with the tangent space of a certain model Klein geometry *Ehresmann connection, gives a manner for differentiating sections of a general fibre bundle * Electrical connection, allows the flow of electrons *Galois connection, a type of correspondence between two partially ordered sets *Affine connection, a geometric object on a smooth manifold which connects nearby tangent spaces *Levi-Civita connection, used in differential geometry and general relativity; differentia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connection-oriented Network
Connection-oriented communication is a network communication mode in telecommunications and computer networking, where a communication session or a semi-permanent connection is established before any useful data can be transferred. The established connection ensures that data is delivered in the correct order to the upper communication layer. The alternative to connection-oriented transmission is connectionless communication, for example the datagram mode communication used by Internet Protocol (IP) and User Datagram Protocol, where data may be delivered out of order, since different network packets are routed independently and may be delivered over different paths. Connection-oriented communication may be implemented with a circuit switched connection, or a packet-mode virtual circuit connection. In the latter case, it may use either a transport layer virtual circuit protocol such as the TCP protocol, allowing data to be delivered in order. Although the lower-layer switching is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Token Bucket
The token bucket is an algorithm used in packet-switched and telecommunications networks. It can be used to check that data transmissions, in the form of packets, conform to defined limits on bandwidth and burstiness (a measure of the unevenness or variations in the traffic flow). It can also be used as a scheduling algorithm to determine the timing of transmissions that will comply with the limits set for the bandwidth and burstiness: see network scheduler. Overview The token bucket algorithm is based on an analogy of a fixed capacity bucket into which tokens, normally representing a unit of bytes or a single packet of predetermined size, are added at a fixed rate. When a packet is to be checked for conformance to the defined limits, the bucket is inspected to see if it contains sufficient tokens at that time. If so, the appropriate number of tokens, e.g. equivalent to the length of the packet in bytes, are removed ("cashed in"), and the packet is passed, e.g., for transm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaky Bucket
The leaky bucket is an algorithm based on an analogy of how a bucket with a constant leak will overflow if either the average rate at which water is poured in exceeds the rate at which the bucket leaks or if more water than the capacity of the bucket is poured in all at once. It can be used to determine whether some sequence of discrete events conforms to defined limits on their average and peak rates or frequencies, e.g. to limit the actions associated with these events to these rates or delay them until they do conform to the rates. It may also be used to check conformance or limit to an average rate alone, i.e. remove any variation from the average. It is used in packet-switched computer networks and telecommunications networks in both the traffic policing, traffic shaping and scheduling of data transmissions, in the form of packets, to defined limits on bandwidth and burstiness (a measure of the variations in the traffic flow). A version of the leaky bucket, the gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-T
The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Communication Technology such as X.509 for cybersecurity, Y.3172 and Y.3173 for machine learning, and H.264/MPEG-4 AVC for video compression, between its Member States, Private Sector Members, and Academia Members. The first meeting of the World Telecommunication Standardization Assembly (WTSA), the sector's governing conference, took place on 1 March of that year. ITU-T has a permanent secretariat called the Telecommunication Standardization Bureau (TSB), which is based at the ITU headquarters in Geneva, Switzerland. The current director of the TSB is Chaesub Lee (of South Korea), whose first 4-year term commenced on 1 January 2015, and whose second 4-year term commenced on 1 January 2019. Chaesub Lee succeeded Malcolm Johnson of the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ATM Forum
The ATM Forum was founded in 1991 to be the industry consortium to promote Asynchronous Transfer Mode technology used in telecommunication networks; the founding president and chairman was Fred Sammartino of Sun Microsystems. It was a non-profit international organization. The ATM Forum created over 200 implementation agreements. History In 1996 ATM technology stabilized with the "Anchorage Accord", which established the baseline of ATM implementations. While ATM did not live up to every expectation, it remained an important core network technology. The Frame Relay Forum (promoting Frame Relay) also started in 1991. The MPLS Forum (which supported Multiprotocol Label Switching had begun in 2000. Those two merged in 2003 to become the MPLS and Frame Relay Alliance (MFA). In 2005, the ATM Forum joined forces with the MFA to form the MFA Forum, which was renamed to be the IP/MPLS Forum. In May 2009 the IP/MPLS Forum merged with the Broadband Forum. Sampling of specifications * AT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priority Control
Prioritization is an action that arranges items or activities in order of importance. Priority may refer specifically to: Law * Priority or right of way on the road, see Traffic ยง Priority (right of way) ** Priority signs, a traffic sign that specifies which route has the right of way * Priority date, a concept of establishing waiting times in the immigration process by United States Department of State * Priority right, a time-limited right, triggered by the first filing of an application for a patent * Subordination (finance), the order of priorities in claims for ownership or interest in various assets Music * ''Priorities'', the debut album by Bedfordshire-based rock band Don Broco *"Priority", a song by Jolin Tsai from the 2004 album '' Castle'' * Priority Records, a record label started in 1985 and acquired by Capitol Records * ''Priority'' (Pointer Sisters album) * ''Priority'' (Imperials album), 1980 Science and technology * Scheduling priority, the way computing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UPC And NPC
Usage Parameter Control (UPC) and Network Parameter Control (NPC) are functions that may be performed in a computer network. UPC may be performed at the input to a network "to protect network resources from malicious as well as unintentional misbehaviour". NPC is the same and done for the same reasons as UPC, but at the interface between two networks. UPC and NPC may involve traffic shaping, where traffic is delayed until it conforms to the expected levels and timing, or traffic policing, where non-conforming traffic is either discarded immediately, or reduced in priority so that it may be discarded downstream in the network if it would cause or add to congestion. Uses In ATM The actions for UPC and NPC in the ATM protocol are defined in ITU-T Recommendation I.371 ''Traffic control and congestion control in B ISDN'' and the ATM Forum's ''User-Network Interface (UNI) Specification''. These provide a conformance definition, using a form of the leaky bucket algorithm called th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
