data of the image. JPEG retains all of the color information of an image and offers varying
degrees of compression.
Network
In information technology, a network is a series of points or nodes interconnected by
communication paths. Networks can interconnect with other networks and contain sub
networks.
NTP
NTP (Network Time Protocol) is a protocol designed to synchronize the clocks of computers
over a network.
POP3
POP3 is a client/server protocol in which e-mail is received and held for you by your Internet
server. POP can be thought of as a "store-and-forward" service. POP and IMAP deal with the
receiving of email, and SMTP is a protocol for simply transferring email across the Internet.
Port number
In programming, a port (noun) is a "logical connection place" and specifically, using the
Internet's protocol, TCP/IP, the way a client program specifies a particular server program on
a computer in a network. For the HTTP service, port 80 is defined as a default and it does
not have to be specified in the Uniform Resource Locator (URL).
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
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