Most Common Networking Terms and Acronyms – E

E1
Wide-area digital transmission scheme used predominantly in Europe that carries data at a rate of 2.048 Mbps. E1 lines can be leased for private use from common carriers. Compare with T1.

E3
Wide-area digital transmission scheme used predominantly in Europe that carries data at a rate of 34.368 Mbps. E3 lines can be leased for private use from common carriers. Compare with T.120. See also DS-3.

EAP
Extensible Authentication Protocol. Framework that supports multiple, optional authentication mechanisms for PPP, including cleartext passwords, challenge-response, and arbitrary dialog sequences.

Edge LSR
Edge Label Switch Router. The role of an Edge LSR is to turn unlabeled packets into labeled packets, and vice versa. Also known as PE (Provider Edge) router in an MPLS network.

encapsulation
Wrapping of data in a particular protocol header. For example, Ethernet data is wrapped 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.

encryption
Application of a specific algorithm to data so as to alter the appearance of the data making it incomprehensible to those who are not authorized to see the information. See also decryption.

encryption certificate
Public-key certificate that contains a public key that is intended to be used for encrypting data, rather than for verifying digital signatures or performing other cryptographic functions.

Encapsulating Security Payload
ESP
an IP-based protocol providing confidentiality services for data. Specifically, ESP provides encryption as a security service to protect the data content of the IP packet. ESP is an Internet standard (RFC 2406).

Ethernet
Baseband LAN specification invented by Xerox Corporation and developed jointly by Xerox, Intel, and Digital Equipment Corporation. Ethernet networks use CSMA/CD and run over a variety of cable types at 10, 100, 1000 Mbps. Ethernet is similar to the IEEE 802.3 series of standards.