E-commerce - The buying and selling of products or services over electronic systems such as the Internet and other computer networks.
Echo Reply - An echo reply is the response a machine that has received an echo request sends over ICMP.
Egress Filtering - Filtering outbound traffic.
Emanations Analysis - Gaining direct knowledge of communicated data by monitoring and resolving a signal that is emitted by a system and that contains the data but is not intended to communicate the data.
Encapsulation - The inclusion of one data structure within another structure so that the first data structure is hidden for the time being.
Encryption - The process of converting data into a cipher or code to prevent unauthorized access.
End user - The intended recipient or user of a product or service.
Ephemeral Port - Also called a transient port or a temporary port. Usually is on the client side. It is set up when a client application wants to connect to a server and is destroyed when the client application terminates. It has a number chosen at random that is greater than 1023.
Ethernet - The most widely-installed LAN technology. Specified in a standard, IEEE 802.3, an Ethernet LAN typically uses coaxial cable or special grades of twisted pair wires. Devices are connected to the cable and compete for access using a CSMA/CD protocol.
Extended ACLs (Cisco) - Extended ACLs are a more powerful form of Standard ACLs on Cisco routers. They can make filtering decisions based on IP addresses (source or destination), Ports (source or destination), protocols, and whether a session is established.
Exterior Gateway Protocol (EGP) - A protocol which distributes routing information to the routers which connect autonomous systems.