E164 NUmber Mapping
E164 NUmber Mapping (ENUM), also refers to "Telephone Number Mapping", is a proposed technology for mapping telephone numbers to the Domain Name System (DNS). ENUM includes a suite of protocols to unify the telephone system with the Internet by using E.164 addresses with DDDS and DNS. ENUM is a DNS-based protocol that is best suited to offer services that not only help facilitate, but expand on ways to complete calls over VoIP networks. It provides a user with a domain name on an E.164 server in order to associate a common international telephone number with a URI and provide other DNS-related services. The server is maintained by the Service Provider and is expected to become standard since it can successfully address locating URIs with nothing more than a common international telephone number.

E2A
E2A is a legacy protocols for providing OAM&P functions between a network element and an operations support system.

EA: Extended Address
Extended Address (EA) refers to a Frame relay address field which extends the addressing structure from a default of 2 bytes to 3 or 4 bytes. EA = 0 indicates that more address follows, and EA = 1 indicates that it is the last address byte.

Early Token Release
Early Token Release is a feature in Token Ring networks that allows a station to release a new token onto the ring immediately after transmitting, instead of waiting for the first frame to return. This feature can increase the total bandwidth on the ring.

EARN: European Academic Research Network
European Academic Research Network (EARN) was the European network connecting universities and research institutes. EARN merged with RARE to form TERENA.

EAS: Expert Agent Selection
Expert Agent Selection(EAS) is a mode for the Lucent Definity ECS ACD. In this mode, agents are added automatically to pre-assigned skill groups at login. Calls can be routed either to the agent's physical extension or to the agent's login ID. In non-EAS mode, agents must add themselves manually to hunt groups, and calls can be routed only to physical extensions.

EBCDIC: Extended Binary Coded Decimal Interchange Code
Extended Binary Coded Decimal Interchange Code (EBCDIC) is coded character set developed by IBM consisting of 8-bit coded characters used on IBM AS/400 and e-Server. EBCDIC is an extension to 8 bits of BCDIC (Binary Coded Decimal Interchange Code), an earlier 6-bit character set used on IBM computers.

EBN: Extended Border Node
Extended border node (EBN) is a network node capable of multiple APPN network connections and can maintain CP-CP connectivity with a network node that has a different NETID. APPN topology information does not cross the extended border node connection or APPN subnetwork boundary, but search requests can, and an LU-LU session can be set up. An APPN subnetwork boundary is assumed when an extended border node is connected to a network node (or extended border node) with a different network identifier.

EBONE: European Backbone
European Backbone(EBONE) is a Pan-European network backbone service.

EBU: European Broadcasting Union
European Broadcasting Union (EBU), founded in 1950 and headquartered in Geneva, is an association of national broadcasters that negotiates broadcasting rights for major sports events, operates the Eurovision and Euroradio networks, organizes program exchanges, stimulates and coordinates co- productions, and provides operational, commercial, technical, legal, and strategic services.

ECC: Error-Correcting Code
Error-Correcting Code (ECC) is a code in which each data signal conforms to specific rules of construction so that departures from this construction in the received signal can generally be automatically detected and corrected. It is used in computer data storage, for example in dynamic RAM, and in data transmission. Examples include Hamming code, Reed-Solomon code, Reed-Muller code, Binary Golay code, convolutional code, turbo code and others. The simplest error correcting codes can correct single-bit errors (single error correction) and detect double-bit errors (double error detection). Other codes can detect or correct multi-bit errors.

Echo
Echo in computer networking is a testing technique where packets are sent to a distant node that isobligated to immediately send the packets back.

Echo Cancellation
Echo Cancellation is a method for removing unwanted signals from the main transmitted voice telephony signal.

Echo Test
Echo Test is a diagnostic test in which packets are sent by one node to another node, which immediately returns them to the original node. The data recorded by the echo test includes the success rate of the return as well as the time needed to complete the round trip.

Echoplex
Echoplex is a computer mode in which keyboard characters are echoed on a terminal screen upon return of a signal from the other end of the line indicating that the characters have been received correctly.

ECM disable
ECM disable is a feature that disables Error Correction Mode (ECM) capability advertised in a fax DIS signal.

ECM: Error Correction Mode
Error Correction Mode(ECM) is an option defined in T.30 and available in many fax machines that allows a fax page to be broken into HDLC-like frames that allow transmission errors to be detected.

ECMA: European Computer Manufacturers Association
European Computer Manufacturers Association (ECMA) is a group of European computer vendors who have done substantial OSI standardization work.

Econet: Economy Network
Economy Network (Econet) was used in the early 1980s by Acorn to provide computer networking for the BBC Micro. Modules were later produced for the BBC Master and Master Compact models, which were even used in the Acorn Archimedes series.

EDC: Error-Detecting Code
Error-Detecting Code (EDC) is a code that can detect transmission errors through analysis of received data based on the adherence of the data to appropriate structural guidelines. Error Detecting Codes require more signal elements than are necessary to convey the basic information.

EDFA: Erbium-doped Fiber Amplifier
Erbium-doped Fiber Amplifier (EDFA) is an optical fiber doped with the rare earth element erbium, which can amplify light in the 1550 nm region when pumped by an external light source.

Edge Device
Edge devices are switches, routers, routing switches, IADs and a variety of MAN/WAN devices which are installed in the edge network to pass packets between the access devices and core/backbone network devices. An edge device does not participate in the running of any network layer routing protocol but it obtains forwarding descriptions using the route distribution protocol. It is a physical device using Data Link layer (layer 2) and Network layer (layer 3) technologies.

Edge LSR
Edge Label Switch Router (Edge LSR) is an edge device in a network that turns unlabeled packets into labeled packets, and vice versa.

EDI: Electronic Data Interchange
Electronic Data Interchange (EDI) is the computer-to-computer exchange of structured information between organizations with a minimum of human intervention. EDI interchange data methods are used for the transfer of business transaction data, such as orders and invoices of the automated purchase of goods and services.

EDIFACT: Electronic Data Interchange for Administration, Commerce, and Transport
Electronic Data Interchange for Administration, Commerce, and Transport (EDIFACT) is the data exchange standard administered by the United Nations to be a multi-industry EDI standard.

eDonkey Network
eDonkey network, also called eDonkey2000 network or ed2k, is a file-sharing network used primarily to exchange music, films and software. Like most file-sharing networks, it is decentralized; files are not stored on a central server, but are exchanged directly between users based on the peer-to-peer principle.

EDUCAUSE
EDUCAUSE is a nonprofit association whose mission is to advance higher education by promoting the intelligent use of information technology.

EENet: Estonian Educational and Research Network
Estonian Educational and Research Network (EENet) is a governmental non-profit organization established in August, 1993, by the Ministry of Education of Estonia with the task of managing, coordinating and developing the computer network of science, education and culture. Since 1997, EENet has operated as a state agency administered by the Estonian Ministry of Education and Research.

EFCI: Explicit Forward Congestion Indication
Explicit Forward Congestion Indication (EFCI), a term in ATM network, is one of the congestion feedback modes allowed by ABR service. A network element in an impending congestion state or in a congested state can set the EFCI. The destination end-system can implement a protocol that adaptively lowers the cell rate of the connection based on the value of the EFCI.

EFF: Electronic Frontier Foundation
Electronic Frontier Foundation (EFF) is a nonprofit group of passionate people lawyers, technologists, volunteers, and visionaries working to protect your digital rights. EFF is a foundation established to address social and legal issues arising from the impact on society of the increasingly pervasive use of computers as the means of communication and information distribution.

Effective Data Transfer Rate
Effective Data Transfer Rate, usually expressed in bits (or characters, blocks, or frames), is the average number of units of data transferred per second from a source and accepted as valid by a receiver.

EFM: Ethernet in the First Mile
Ethernet in the First Mile (EFM) is an effort to extend Ethernet technology's reach over the access line between end users and carriers. The "first mile" refers to the link between the subscriber, or user, and the public network. Ethernet in the First Mile allows the subscriber to have a familiar Ethernet interface connection, meaning faster speed and faster Internet access. Ethernet in the First Mile offers the ultimate connectivity and bandwidth for multimedia applications. Ethernet in the First Mile also hopes to make optical Ethernet a low-cost alternative to DSL and cable modems.

Egress
Egress refers to the traffic leaving the network.

EHSA: Enhanced High System Availability
Enhanced High System Availability (EHSA) is a processor redundancy scheme that reduces switchover time by requiring that the redundant processor be running in a hot standby mode.

EIA/TIA-232
EIA/TIA-232, formerly called RS-232, is the common physical layer interface standard, developed by EIA and TIA. EIA/TIA-232 supports unbalanced circuits at signal speeds of up to 64 kbps, which closely resembles the V.24 specification.

EIA/TIA-449
EIA/TIA-449, formerly called RS-449, is a popular physical layer interface developed by EIA and TIA. EIA/TIA-449, essentially, is a faster (up to 2 Mbps) version of EIA/TIA-232 capable of longer cable runs.

EIA/TIA-586
EIA/TIA-586 is a standard developed by EIA and TIA that describes the characteristics and applications for various grades of UTP cabling.

EIA: Electronic Industries Alliance
The Electronic Industries Alliance (EIA) is a US national trade organization that includes the full spectrum of U.S. manufacturers. The Alliance is a partnership of electronic and high-tech associations and companies whose mission is promoting the market development and competitiveness of the U.S. high-tech industry through domestic and international policy efforts. EIA, headquartered in Arlington, Va., comprises nearly 1,300 member companies whose products and services range from the smallest electronic components to the most complex systems used by defense, space and industry, including the full range of consumer electronic products. EAI specifies electrical transmission standards. The EIA and the TIA have developed numerous well-known communications standards, including EIA/TIA-232 and EIA/TIA-449.

EIA-422
EIA-422, formerly known as RS-422, is a serial data communication protocol which specifies 4 wire, full-duplex, differential line, multi-drop communications. It provides for balanced data transmission with unidirectional/non-reversible, terminated or non-terminated transmission lines. EIA-422 does not allow multiple drivers but only multiple receivers.

EIA-485
EIA-485, formerly known as RS-485 or RS485, is a physical layer electrical specification of a two-wire, half-duplex, multipoint serial connection. The standard specifies a differential form of signalling. The difference between the wires voltages is what conveys the data. One polarity of voltage indicates a logic 1 level, the reverse polarity indicates logic 0.

EIA-530
EIA-530 refers to two electrical implementations of EIA/TIA-449: RS-422 for balanced transmission and RS-423 for unbalanced transmission.

EIP: Ethernet Interface Processor
Ethernet Interface Processor (EIP) is an interface processor card that provides high-speed (10-Mbps) AUI ports that support Ethernet Version 1 and Ethernet Version 2 or IEEE 802.3 interfaces, and a high-speed data path to other interface processors.

EIRP: Effective Isotropic Radiated Power
Effective Isotropic Radiated Power (EIRP) is a term for the expression of the performance of an antenna in a given direction relative to the performance of a theoretical (isotropic) antenna and is expressed in watts or dBW. EIRP is the sum of the power sent to the antenna plus antenna gain.

EISA: Extended Industry-Standard Architecture
Extended Industry Standard Architecture (EISA) is a bus architecture designed for PCs using an Intel 80386, 80486, or Pentium microprocessor. EISA extends the ISA bus architecture to 32 bits and allows more than one CPU to share the bus. The bus mastering support is also enhanced to provide access to 4 GB of memory. Unlike MCA, EISA can accept older XT and ISA boards — the lines and slots for EISA are a superset of ISA.

E-ISUP: Extended-ISUP
Extended-ISUP, originally a subset of Q.761 ISUP, is expanding in to a superset of ITU and ANSI ISUP. In addition, it supports the delivery of SDP parameters via generic digits. E-ISUP runs over IP and therefore uses IP addresses instead of point codes.

ELAN: Emulated LAN
Emulated LAN (ELAN) is an ATM technology which an Ethernet or Token Ring LAN is emulated using a client-server model. ELANs are composed of an LEC, an LES, a BUS, and an LECS. Multiple ELANs can exist simultaneously on a single ATM network. ELANs are defined by the LANE specification.

Electromagnetic Spectrum
Electromagnetic Spectrum refers to the full range of electromagnetic frequencies, which include Radio Frequency (RF).

EMA: Enterprise Management Architecture
Enterprise Management Architecture (EMA) is the Digital Equipment Corporation (DEC, now part of HP) network management architecture, based on the OSI network management model.

E-mail: Electronic mail
Electronic mail (E-Mail or Email) is a widely used network application in which messages and documents are transmitted electronically between end users over various types of networks using various network protocols.

EMI: Electromagnetic Interference
Electromagnetic Interference (EMI) is the interference by electromagnetic signals that can cause reduced data integrity and increased error rates on transmission channels.

EMIF: ESCON Multiple Image Facility
ESCON Multiple Image Facility (EMID) is the mainframe I/O software function that allows one Enterprise System Connection (ESCON) channel to be shared among multiple logical partitions on the same mainframe.

EMP: Electromagnetic Pulse
Electromagnetic Pulse (EMP) is caused by lightning and other high-energy phenomena. EMP is capable of coupling enough energy into unshielded conductors to destroy electronic devices.

EMS: Element Management System
An Element Management System (EMS) manages one or more of a specific type of network elements (NEs). An EMS allows the user to manage all the features of each NE individually, but not the communication between NEs - this is done by the network management system (NMS). NEs expose one or more management interfaces that the EMS uses to communicate with and to manage them. These management interfaces use a variety of protocols including SNMP, TL1, CLI, XML, and CORBA.

EMTOX: Exchange of Mixed Traffic over X.25
Exchange of Mixed Traffic over X.25 (EMTOX) is a specification for transmitting airline protocol data over standard X.25 switched virtual circuits (SVCs).

Emulation
Emulation is a network activity in which a computer acts as if it is another kind of computer or terminal. For example, a PC user opens a remote terminal session to a Unix, it may run a program that emulates an Unix terminal.

Emulation Mode
Emulation Mode is an operational state of a computer when it is running a foreign program under emulation. For example, a PC user opens a remote terminal session to a Unix and it may run a program that emulates an Unix terminal.

Emultiplexing
Emultiplexing refers to the process of separating of multiple input streams (that were multiplexed into a common physical signal) back into multiple output streams.

EN: End Node
End Node (EN), a term in the IBM APPN, is an end system that implements the PU 2.1, provides end-user services, and supports sessions between local and remote CPs. ENs are not capable of routing traffic and rely on an adjacent Network Node (NN) for APPN services.

Encapsulating or Encapsulation
Encapsulation means the inclusion of one data structure within another structure so that the first data structure is hidden for the time being. Encapsulating is a technique used by layered protocols in which a low level protocol accepts a message from a higher level protocol, then places it in the data portion of the lower-level frame. The logistics of encapsulation require that packets traveling over physical network contain a sequence of headers. The first header derives from the physical network frame, the second from the data link frame, the third from the network frame, and so on. Encapsulation enables the transmission of data over different network portions based on differing protocols.

Encapsulating
Encapsulating data is a technique used by layered protocols in which a low level protocol accepts a message from a higher level protocol, then places it in the data portion of the lower-level frame. The logistics of encapsulation require that packets traveling over physical network contain a sequence of headers. The first header derives from the physical network frame, the second from the IP frame, the third from the physical network frame, and so on. Encapsulation enables the transmission of data over different network portions based on differing protocols.

Encapsulation
Encapsulation means the inclusion of one data structure within another structure so that the first data structure is hidden for the time being. For example, Ethernet data is encapsulated in a specific Ethernet header before network transit. Also, when bridging dissimilar networks, the entire frame from one network is simply placed in the header used by the data link layer protocol of the other network.

Encapsulation Bridging
Encapsulation bridging encloses the Ethernet frame into the FDDI frame, allowing it to be moved from one Ethernet to the other across the FDDI backbone. Once the packet has arrived at the destination bridge, it needs to be de-encapsulated before being forwarded to the host on the destination Ethernet.

Encoder
Encoder is a device (hardware, software or both) that modifies information into certain format for viewing, editing, storage and transmission. This is usually done by means of an algorithm, especially if any part is digital, while most analogue is done with circuitry. For example, software that turns uncompressed WAV (Windows) or AIFF files into compressed files, using a CODEC such as MP3 or RealAudio. A decoder is required to convert the encoded information back to its original format, if necessary.

Encoding
Encoding is the process of converting the analog electrical or optical signals to certain digital format for storage, manipulation, and display by a computer. Encoding also means transfering digital information from one format to another format for a specific purpose such as data compression.

End Point or Endpoint
End Point, or endpoint, generally means the beginning or final point in a process. In networking, it may refers to the device at which a virtual circuit or virtual path begins or ends. In VOIP process, endpoint is the SIP or H.323 terminal or gateway. An endpoint can call and be called. It generates and terminates the information stream.

End-to-end Principle
The end-to-end principle is one of the central design principles of the Internet Protocol (IP) that is the basis of the Internet. It states that, whenever possible, communications protocol operations should be defined to occur at the end-points of a communications system. Reliable systems tend to require end-to-end processing to operate correctly, in addition to any processing in intermediate system.

Enterprise Network
Enterprise Network is the network that allows communication and resource-sharing among all of a company's business functions and workers. In some cases, Enterprise network would even include the company's suppliers, contractors and distributors.

Enterprise Project Management
In Information Technology, Enterprise Project Management means enterprise-wide network administration, which is becoming increasingly complex. The corporate network environment is no longer tied to a single vendor, let alone a single platform.

Entity
Entity in networking refers to an individual, manageable network device. Entity is sometimes called an alias.

Entity Identifier
Entity Identifier is the unique address of a network-visible entity (NVE) socket in a node on an AppleTalk network. The specific format of an entity identifier is network-dependent.

Entity Name
Entity Name is the name/aliase that network-visible entity (NVE) can assign to itself in an AppleTalk network. Although not all NVEs have names, NVEs can possess several names (or aliases). An entity name is made up of three character strings: object, entity type, and zone. For example: Bldg 5 Laser Printer 8:LaserWriter@Bldg 5 Zone.

Entity Type
Entity Type is part of an entity name of the network-visible entity (NVE) in an AppleTalk network. It describes the entity's class. For example, LaserWriter or AFPServer.

ENUM: E164 NUmber Mapping
Electronic Numbering (ENUM or Enum), also refered to as "E164 NUmber Mapping" or "Telephone Number Mapping", is a suite of protocols to unify the telephone system with the Internet by using E.164 addresses with Dynamic Delegation Discovery System (DDDS) and Domain Name System (DNS). ENUM is a standard adopted by the Internet Engineering Task Force (IETF) that uses the domain name system (DNS) to map telephone numbers to Web addresses or uniform resource locators (URL). The goal of the ENUM standard is to provide a single number to replace the multiple numbers and addresses for an individual's home phone, business phone, fax, cell phone, and e-mail.

EOM: End Of Message
End Of Message(EOM) is the indicator that identifies the last ATM cell containing information from a data packet that was segmented.

EoS: Ethernet over SONET/SDH
Ethernet over SONET/SDH (EoS) refers to a group of industry standard specifications for optimal transport of Ethernet through SONET/SDH, because Ethernet is not directly supported over the SONET/SDH network traditionally. Basically, EoS capability turns the Sonet/SDH MAN/WAN infrastructure backbone into a transparent Ethernet segment for attached servers and clients.

EOT: End of Transmission
End of Transmission (EOT) is typically a character that signifies the end of a logical group of characters or bits.

EPD: Early Packet Discard
Early Packet Discard (EPD) is a mechanism used by some ATM switches for discarding a complete AAL5 frame when a threshold condition, such as imminent congestion, is met. EPD prevents congestion that would otherwise jeopardize the switch's capability to properly support existing connections with a guaranteed service.

ER: Explicit Rate
Explicit Rate (ER), in ATM, is an RM cell used to limit the ACR for a transmission to a specific value. Usually the source sets the ER initially to a requested rate, such as the PCR. Later, any network element in the path can reduce the ER to a value that the element can sustain.

Error Control
Error Control refers to the techniques for detecting and correcting errors in data transmissions.

ES: End System
End System (ES), a concept in an OSI network, refers to a host or node in an OSI network. The other key concept in an OSI network is the Intermediate System (IS), which refers to routers and switches that pass information through the network.

ES: Errored Second
Errored Second (ES) is a one-second interval during which one or more errors are detected; a PM parameter, measured on a per-channel basis.

ESCON Channel
Enterprise System Connection (ESCON) Channel is an IBM channel for attaching mainframes to peripherals, such as storage devices, backup units, and network interfaces. This channel incorporates fiber channel technology. The ESCON channel replaces the bus and tag channel.

ESCON: Enterprise System Connection
Enterprise System Connection (ESCON) is an IBM channel architecture that specifies a pair of fiber-optic cables, with either LEDs or lasers as transmitters, and a signaling rate of 200 Mbps.

ESD: Electrostatic Discharge
Electrostatic Discharge (ESD) refers to the discharge of stored static electricity that can damage electronic equipment and impair electrical circuitry, resulting in complete or intermittent failures.

ESI: End System Identifier
End System Identifier (ESI) is a unique six-byte number corresponding to the MAC address of LAN technologies like Ethernet. ESI distinguishes multiple nodes at the same level when the lower level peer group is partitioned (usually an IEEE 802 address).

Esnet: Energy Sciences Network
Energy Sciences Network (Esnet) is a data communications network managed and funded by the U.S. Department of Energy Office of Energy Research (DOE/OER). Esnet serves thousands of Departments of Energy scientists and collaborators worldwide at national laboratories, universities and other institutions. Esnet is managed and operated by the ESnet staff at Lawrence Berkeley National Laboratory.

ETH Unit: Ethernet Unit
Ethernet Unit (ETH Unit) is the interface to the Management Bus Concentrator and the network management system (NMS).

EtherChannel
EtherChannel is a logical aggregation of multiple Ethernet interfaces used to form a single higher bandwidth routing or bridging endpoint. EtherChannel technology is a trunking technology that allows grouping several Ethernet links and is capable of load balancing traffic across those links. Traffic is distributed across the links, providing higher performance and redundant parallel paths. When a link fails, traffic is redirected to the remaining links within the channel without user intervention and with minimal packet loss.

Ethereal
Ethereal, now called Wireshark, is an open source and popular network troubleshooting and packet sniffing tool for both UNIX and Microsoft Windows operating systems. Similar to tcpdump but with a well-designed GUI and many more information sorting and filtering options, Ethereal allows the user to see all traffic being passed over the network by putting the network card into a promiscuous mode. It could be used by hackers to view network traffic information without authorization.

Ethernet
Ethernet is the most popular local area network (LAN) technology implemented worldwide. Ethernet was first developed in early 1970s. Basically, Ethernet includes a shared transmission medium such as a twisted pair cable or co-axial cable and a multi-port hub, bridge or switch. Computers, printers and workstations are connected to each other through the hub/switch/bridge using the cables in a star-like or a bus-like configuration. Ethernet originally supported a maximum theoretical data rate of 10 megabits per second (Mbps). Later, Fast Ethernet standards increased this maximum data rate to 100 Mbps. Today, Ethernet technology further extends peak performance up to 1Gbps and 10 Gbps.

Ethernet hub
Ethernet Hub or repeater is a device that accepts numerous Ethernet connections from network devices and cross-connects them, making them act as a single segment. Data arriving via the receive pair of one connection is regenerated and sent out on the transmit pair to all connected devices except for the device who originated the transmission. Ethernet Hub works at the physical layer of the OSI model. If a signal comes into two ports at the same time when a collision occurs, so every attached device shares the same collision domain. Hubs support only half duplex Ethernet, providing bandwidth which is shared among all the connected devices.

Ethernet Meltdown
Ethernet Meltdown refers to an event that causes saturation, or near saturation, on an Ethernet. It usually results from illegal or misrouted packets and typically lasts only a short time.

Ethernet VPN
Ethernet VPN refers to a group of technologies to provide Virtual Private Network services over the Internet between the Ethernet LANs. One of the Ethernet VPN technologies is based on Virtual Private LAN Services (VLPS) and Multiprotocol Label Switching (MPLS), which provides more benefits than other alternative layer 2 or 3 VPN technologies.

EtherType
EtherType is a field in the Ethernet II frame, which indicates the protocol used in the data field of the frame. According to the IEEE 802.3, Length/EtherType Field is a two-octet field which takes one of two meanings, depending on its numeric value. For numeric evaluation, the first octet is the most significant octet of this field. When the value of this field is greater than or equal to 1536 decimal (equal to 0600 hexadecimal) the EtherType Field indicates the nature of the MAC client protocol (EtherType interpretation). The length and EtherType interpretations of this field are mutually exclusive.

ETSI: European Telecommunications Standards Institute
European Telecommunications Standard Institute (ETSI) is an independent, non-profit organization, whose mission is to produce telecommunications standards for today and for the future. Based in France, ETSI is officially responsible for standardization of Information and Communication Technologies (ICT) within Europe. These technologies include telecommunications, broadcasting and related areas such as intelligent transportation and medical electronics.

EUnet: European Internet
European Internet (EUnet) is a European commercial Internet service provider. EUnet is designed to provide e-mail, news, and other Internet services to European markets.

E-Work
E-Work is an amplification of the original 1980s and 1990s concepts of Telework or Telecommuting which is extensively used in Europe. The new concept of E-work extends the purely physical aspects of the old European telework and US telecommuting concepts to include social dynamics; for example, the influence on how we work of factors such as networks of excellence, flexible working practices, roles and relationships between managers, workers and clients when working using Information and Communications Technology (ICT) tools.

EWOS: European Workshop for Open Systems
European Workshop for Open Systems (EWOS) is the OSI Implementors Workshop for Europe.

Excess Rate
Excess Rate refers to the traffic in excess of the insured rate for a given connection. Specifically, the excess rate equals the maximum rate minus the insured rate. Excess traffic is delivered only if network resources are available and can be discarded during periods of congestion.

EXeem
EXeem is a free Peer to Peer (P2P) client built on the BitTorrent network protocol and programming interface. EXeem supports multi-source downloads and opening of torrent files. However, eXeem does not connect directly to the main BitTorrent P2P network but rather to its own private network.

EXeem Lite
eXeem Lite, a simpler version of eXeem, is a free Peer to Peer (P2P) client built on the BitTorrent network protocol and programming interface. Both clients offer similar functionality in other respects. Both run only on Windows operating systems.

Expansion Card
An expansion card in computing is a printed circuit board that can be inserted into an expansion slot of a computer motherboard to add additional functionality to a computer system. One edge of the expansion card holds the contacts that fit exactly into the slot. They establish the electrical contact between the electronics (mostly integrated circuits) on the card and on the motherboard.

Expedited Delivery
Expedited Delivery is an option set by a specific protocol layer telling other protocol layers (or the same protocol layer in another network device) to handle specific data more rapidly.

Explicit Path
Explicit path is a pre-defined route or path by the message originator for a message to travel from the sender to the receiver. This may happen in an IP-based network. In this case, it is called the IP Explicit Path.

Explicit Route
Explicit Route, a term in the IBM SNA, refers to a route from a source subarea to a destination subarea, as specified by a list of subarea nodes and transmission groups that connect the two.

Explorer Frame
Explorer Frame is the frame sent out by a networked device in a Source-Route Bridging (SRB) environment to determine the optimal route to another networked device.

Explorer Packet
Explorer Packets are generated by an end station trying to find its way through a SRB network. Gathers a hop-by-hop description of a path through the network by being marked (updated) by each bridge that it traverses, thereby creating a complete topological map. There are a few types of Explorer Packets: all-routes explorer packet, local explorer packet, and spanning explorer packet.

Extended Label ATM Interface
Extended Label ATM Interface is a type of interface supported by the remote ATM switch driver and a particular switch-specific driver that supports MPLS over an ATM interface on a remotely controlled switch.

Exterior Router
In internetworking, Exterior Router refers to the gateway to the outside of the autonomous system, because it is expected to communicate with routers on networks outside of the autonomous system. In an AppleTalk network, Exterior Router refers to a type of router connected to an AppleTalk Update-based Routing Protocol (AURP) tunnel, responsible for the encapsulation and the deencapsulation of AppleTalk packets in a foreign protocol header (for example, IP).

External ATM Interface
External ATM Interface is one of the interfaces on the controlled ATM switch other than the switch control port. It is also known as an exposed ATM interface because it is available for connections outside the label-controlled switch.

Extranet
An extranet is a private network that uses Internet technology and the public telecommunication system to securely share part of a business's information or operations with suppliers, vendors, partners, customers, or other businesses. An extranet can be viewed as part of a company's intranet that is extended to users outside the company (e.g., normally over the Internet). It has also been described as a "state of mind" in which the Internet is perceived as a way to do business with other companies as well as to sell products to customers.