PPPOE
PPPOE (Point-to-Point Protocol over Ethernet) is a specification for connecting
multiple computer users on an Ethernet local area network to a remote site through
common customer premises equipment, which is the telephone company's term for a
modem and similar devices. PPPOE can be used to have an office or building-full of
users share a common Digital Subscriber Line (DSL), cable modem, or wireless
connection to the Internet. PPPOE combines the Point-to-Point Protocol (PPP),
commonly used in dialup connections, with the Ethernet protocol, which supports
multiple users in a local area network. The PPP protocol information is encapsulated
within an Ethernet frame.
Proxy Server
A proxy server is associated with or part of a gateway server that separates the
enterprise network from the outside network and a firewall server that protects the
enterprise network from outside intrusion. To the user, the proxy server is invisible.
SMTP
SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and
receiving e-mail. However, since it is limited in its ability to queue messages at the
receiving end, it is usually used with one of two other protocols, POP3 or IMAP, that
let the user save messages in a server mailbox and download them periodically from
the server. In other words, users typically use a program that uses SMTP for sending
e-mail and either POP3 or IMAP for receiving e-mail.
Subnet Mask
Once a packet has arrived at an organization's gateway or connection point with its
unique network number, it can be routed within the organization's internal gateways
using the subnet number as well. The subnet mask allows router know whether two
IP addresses belong to the same subnet.
TCP/IP
TCP (Transmission Control Protocol) is a set of rules (protocol) used along with the
Internet Protocol (IP) to send data in the form of message units between computers
over the Internet. While IP takes care of handling the actual delivery of the data, TCP
takes care of keeping track of the individual units of data (called packets) that a
message is divided into for efficient routing through the Internet.
WEP
WEP is the short form of Wired Equivalent Privacy. It is a security protocol for
wireless local area networks (WLANs) defined in the 802.11b standard. With less
secure physical structure than LAN, WLANs are more vulnerable to tampering. WEP
is to provide security by encrypting data over radio waves from one end point to
another.
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