Jabber Lock-Up
Jabber Lock-Up is a scheme in hubs to ensure that the network is not disabled due to transmission of excessively long data packets. This protection scheme will automatically interrupt the reception of abnormally long streams of data to prevent jabber lock-up. Jabber lock-up protects the medium from being overrun with data packets from a possibly defective device.

Jacobson's algorithm
Jacobson's algorithm is a set of congestion-avoidance and control algorithms that introduces the use of a congestion window (cwnd) to regulate the data-sending rate in TCP. Jacobson's algorithm is implemented in all modern TCP implementations.

JANET: Joint Academic NETwork
Joint Academic NETwork (JANET) is a British government-funded computer network dedicated to education and research. All further- and higher-education organizations are connected to JANET, as are all the Research Councils and several metropolitan area networks in the UK. JANET is operated by a consortium known as the United Kingdom Education and Research Networking Association (UKERNA), who is also responsible for the .ac.uk and .gov.uk domains.

JIDM: Joint Inter-Domain Management
Joint Inter-Domain Management (JIDM) is a technology that defines how network management components based on OSI and SNMP can interoperate with CORBA-based components. The JIDM architecture enables the construction of gateways as well as the construction of pure CORBA-based network management systems, while well interoperate with OSI CMIP and IP based SNMP. It can also be used to implement dual agents, i.e. agents supporting both Q3 and CORBA interfaces. JIDM specifications are defined by a task force under the Open Group.

Jitter
In data networking, jitter is a measure of the variability over time of the latency across a network. A very low amount of jitter is important for real-time applications using voice and video. Jitter may also means that the analog communication line distortion caused by the variation of a signal from its reference timing positions.

Jitter buffer
Jitter buffers, also known as de-jitter buffers, are used to counter "jitter" introduced by packet networks so that a continuous playout of audio ( or video) transmitted over the network can be ensured. The maximum jitter that can be countered by a de-jitter buffer is equal to the buffering delay introduced before starting the play-out of the media-stream.

JTAPI: Java Telephony Application Programming Interface
Java Telephony Application Programming Interface (JTAPI), a call control model developed by Sun Microsystems, is an extensible API that offers an interface to all call control services. The services include those needed in a consumer device up to those of enterprise call centers. JTAPI is part of the JavaPhone API.

Jumper
Jumper may refer to the following things: (1) a wire that connects equipment and cable on a distributing frame in a telephone system. (2) when called as a jumper wire, it is a wire or connector used to establish a circuit for testing. (3) a metal bridge that connects parts of an electrical circuit that can be used to configure expansion boards. (4) an electrical switch consisting of a number of pins and a connector that can be attached to the pins in a variety of ways.

Junction
A junction is a point in the telecommunications network that comprises a switching office or facility cross-connect and/or ADM hardware, a point of connectivity where multiple fiber links come together, and/or a source or destination for a wavelength path.

JUNET: Japan UNIX Network
Japan UNIX Network (JUNET) is a noncommercial network in Japan. It is designed to promote communications between Japanese and other researchers.

JvNCnet: John von Neumann Computer Network
John von Neumann Computer Network (JvNCnet), also known as John von Neumann National Supercomputer Center Network, was a regional network, composed of T1 and slower serial links providing mid-level networking services to sites in the Northeastern United States. It is no longer in service.

JXTA: Juxtapose
Juxtapose (JXTA) is an Open Source peer-to-peer platform created by Sun Microsystems. This platform is defined as a set of XML-based protocols that allow any device connected to a network to exchange messages and collaborate in spite of the network topology. JXTA is was designed to allow a wide range of devices -- PCs, mainframes, cell phones, PDAs -- to communicate in a decentralized manner.

Network, Networking Technology, Data Communication Terms, Glossary and Dictionary - K

KA9Q
KA9Q, also called KA9Q NOS or simply NOS, was a popular early implementation of TCP/IP and associated protocols for amateur packet radio systems and smaller personal computers connected via serial lines. It was named after the amateur radio callsign of Phil Karn, who first wrote the software for a CP/M system and then ported it to DOS on the IBM PC. KA9Q NOS is obsolete now. For some people, KA9Q is also a name for the IP-over-IP Tunneling protocol.

Kad Network
The Kad Network is a completely decentralized file sharing network that does not make use of central servers. It implements the Kademlia P2P overlay protocol. Currently, two client programs use this network: eMule and MLdonkey. The majority of users on the Kad network are also connected to servers on the eDonkey network, and Kad network clients typically query known nodes on the eDonkey network in order to find an initial node on the Kad network.

Kademlia
Kademlia is an overlay network protocol for decentralized peer-to-peer computer networks. It specifies the structure of the network, regulates communications between nodes and how the exchange of information has to take place. Kademlia nodes communicate among themselves using the transport protocol UDP. Kademlia nodes store data by implementing a distributed hash table.

Karn's Algorithm
Karn's Algorithm is an algorithm used in the TCP to improve round-trip time estimations by helping transport layer protocols such as TCP distinguish between good and bad round-trip time samples. Karn's algorithm can prevent erroneous segment Round Trip Time (RTT) measurements due to segment retransmissions. Karn's algorithm was originally designed to be used in packet radio networks, and it is very resistant to packet loss. The problem with Karn's algorithm is that it does not adapt to high variations of delay.

Kazaa Lite K++
Kazaa Lite K++ is a later versions of Kazaa Lite included K++, which added a memory patcher that removed search limit restrictions, multi-source limits, and set one's "participation level" to the maximum of 1000. KaZaA Lite K++ has the ability to resume downloads, play files, block your IP address from the RIAA. Kazaa Lite K++ is obsolete and replaced by Kazaa Lite Resurrection (or simply Kaza Lite).

Kazaa Lite Resurrection
Kazaa Lite Resurrection, also known as Kazaa Lite, is a P2P file sharing client that supports the FastTrack P2P network. Kazaa Lite Resurrection is to continue the development forward on the now obsolete Kazaa Lite K++ application. Kazaa Lite Resurrection technology utilizes the core of Kazaa Media Desktop (KMD) and runs on Windows. Kazaa Lite Resurrection does not contain any adware or spyware. It also offers numerous improvements over KMD such as no bit-rate limits, expanded support for multi-source downloads, and additional P2P tools.

Kazaa Lite Revolution
Kazaa Lite Revolution is an alternative, unauthorized FastTrack P2P network client. Kazaa Lite Revolution, instead of Kazaa Media Desktop, may be used to connect to FastTrack. Revolution is sometimes advertised as an improved version of KMD. Their appearance is similar, but Revolution removes all advertising and adds several new features and tools. Kazaa Lite Revolution is a different application from Kazaa Lite Resurrection.

Kazaa or Kazzaa
Kazaa, also spelled as Kazzaa, is a free, peer-to-peer file sharing service over the Internet. To use Kazaa, a person downloads and installs a software client of Kazaa. Kazaa clients communicate with various registration servers, using Internet protocols, to identify files for sharing or download. The Kazaa P2P network holds peer registration information and then brokers connections between any two peer clients for file sharing.

Kb: Kilobit
Kilobit (Kb) is a measure of data units which is approximately 1,000 bits.

KB: Kilobyte
Kilobyte(KB) is a measure of data units, which is approximately 1,000 bytes (8000 bits).

Kbps: Kilobits Per Second
Kilobits Per Second (Kbps) is a measure of data transmission speed, which is a bit rate expressed in thousands of bits per second. Kilobytes Per Second (KBps) is eight times more than the Kilobits Per Second (Kbps).

KBps: Kilobytes Per Second
Kilobytes Per Second (KBps) is a measure of data transmission speed, which is a bit rate expressed in thousands of bytes per second. Kilobytes Per Second (KBps) is eight times more than the Kilobits Per Second (Kbps).

Keepalive Interval
Keepalive Interval is a period of time between each keepalive message sent by a network device.

Keepalive Message
Keepalive Message is the message sent by one network device to inform another network device that the virtual circuit between the two is still active.

K-Lite: Kazaa Lite
Kazaa Lite, also known as K-Lite, is a peer-to-peer file-sharing computer program. Kazaa Lite is an unauthorized modification of the Kazaa Media Desktop application which excludes adware and spyware and provides slightly extended functionality. It became available in April 2002. It can be downloaded free of charge, and as of mid-2005 is almost as widely used as the official Kazaa client itself. It connects to the same FastTrack network and thus allows to exchange files with all Kazaa users

KVA: Kilovolt-ampere
Kilovolt-ampere (KVA), a measure of power, is one thousand Volt Amperes. KVA equals to that the current flowing in a circuit multiplies by the voltage of that circuit, usually measured on a transformer. One kVA typically equals approximately 0.8 kWh (depending upon the phase).