gloss_E

E

E1.

In Europe, E1 is the basic telecommunications carrier, and it operates at 2.048Mbits/sec. In the U.S., the basic carrier is T1, which operates at 1.544Mbits/sec.

EBCDIC

Extended Binary Code for Data Interchange is IBM's standard for representing alphanumeric characters in an 8-bit field; it can be compared with the more familiar ASCII encoding scheme. However, EBCDIC (pronounced "eb'-sidik") is different from ASCII, and therefore translation is a common function of SNA gateways and terminal emulators. In EBCDIC, for example, an uppercase a is hex C1, a lowercase a is 81, and the number 5 is F5; in ASCII, those characters are hex 41, 61, and 35, respectively. See IBM 3270, IBM 5250.

electromagnetic interference/radio frequency interference (EMI/RFI).

EMI and RFI are forms of noise on data transmission lines that reduce data integrity. EMI is caused by motors, machines, and other generators of electromagnetic fields. RFI is caused by radio waves.

Electronic Data Interchange (EDI).

EDI is a method of electronically exchanging business documents, such as purchase orders, bills of lading, and invoices. Customers and their suppliers can set up EDI networks. EDI can be accomplished through OSI standards or through proprietary products.

electronic mail.

E-mail is an application that enables users to send messages and files over their computer networks. E-mail can range from a simple text-based system to a messaging system that accommodates graphics, faxes, forms-processing, workflow, and more.

encapsulation.

Encapsulation or tunneling is the process of encasing one protocol into another protocol's format. For example, AppleTalk is often encapsulated into TCP/IP for transmission over a WAN because TCP/IP is more efficient over a WAN.

End System To Intermediate System (ES-IS).

ES-IS is an OSI routing protocol that provides the capabilities for hosts (or end systems) and routers (or intermediate systems) to find each other. ES-IS does not handle the router-to-router protocols; the Intermediate System to Intermediate System protocol does.

end system.

In Internet terminology, an end system is a host computer.

Enterprise Management Architecture (EMA).

EMA once was Digital Equipment Corp.'s umbrella architecture for managing enterprise networks. EMA is a distributed approach.

enterprise network.

An enterprise network is one that connects every computer in every location of a company and runs the company's mission-critical applications.

Enterprise RMON

A proprietary extension of RMON and RMON-2, Enterprise RMON was developed by NetScout Systems (formerly Frontier Software Development) and is supported by several other vendors , including Cisco Systems. Enterprise RMON's extensions monitor FDDI and switched LANs. See RMON, RMON-2.

Ethernet.

Ethernet is a CSMA/CD network that runs over thick coax, thin coax, twisted-pair, and fiber- optic cable. A thick coax Ethernet and a thin coax Ethernet use a bus topology. Twisted-pair Ethernet uses a star topology. A fiber Ethernet is point-to-point. DIX or Blue Book Ethernet is the name of the Digital Equipment Corp., Intel, and Xerox specification; 802.3 is the IEEE's specification; 8802/3 is the ISO's specification.

EtherTalk.

EtherTalk is Apple Computer's implementation of Ethernet.