19216811.liveCable/DSL 4-Port Router
POP3
(
P
ost
O
ffice
P
rotocol
3
) - A standard mail server commonly used on the
Internet. It provides a message store that holds incoming e-mail until users log
on and download it. POP3 is a simple system with little selectivity. All pending
messages and attachments are downloaded at the same time. POP3 uses the
SMTP messaging protocol.
Port
- A pathway into and out of the computer or a network device such as a
switch or router. For example, the serial and parallel ports on a personal com-
puter are external sockets for plugging in communications lines, modems, and
printers.
Port Mirroring
- Port mirroring, also known as a roving analysis port, is a
method of monitoring network traffic that forwards a copy of each incoming
and outgoing packet from one port of a network switch to another port where
the packet can be studied. A network administrator uses port mirroring as a
diagnostic tool or debugging feature, especially when fending off an attack. It
enables the administrator to keep close track of switch performance and alter it
if necessary. Port mirroring can be managed locally or remotely.
PPPoE
(
P
oint to
P
oint
P
rotocol
o
ver
E
thernet) - PPPoE is a method for the
encapsulation of PPP packets over Ethernet frames from the user to the ISP
over the Internet.
One reason PPPoE is preferred by ISPs is because it provides
authentication (username and password) in addition to data transport.
A PPPoE
session can be initiated by either a client application residing on a PC, or by
client firmware residing on a modem or router.
PPTP
(
P
oint-to-
P
oint
T
unneling
P
rotocol) - A protocol which allows the Point
to Point Protocol (PPP) to be tunneled through an IP network. PPTP does not
specify any changes to the PPP protocol but rather describes a “tunneling serv-
ice” for carrying PPP (a tunneling service is any network service enabled by tun-
neling protocols such as PPTP, L2F, L2TP, and IPSEC tunnel
RIP
(
R
outing
I
nformation
P
rotocol) - A simple routing protocol that is part of
the TCP/IP protocol suite. It determines a route based on the smallest hop count
between source and destination. RIP is a distance vector protocol that routine-
ly broadcasts routing information to its neighboring routers.
RJ-11
(
R
egistered
J
ack-
11
) - A telephone connector that holds up to six wires.
The RJ-11 is the common connector used to plug a telephone into a wall.
RJ-45
- A connector similar to a telephone connector that holds up to eight
wires, used for connecting Ethernet devices.
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Network Everywhere
™
Series
Notebook (PC)
- A notebook computer is a battery-powered personal comput-
er generally smaller than a briefcase that can easily be transported and conve-
niently used in temporary spaces such as on airplanes, in libraries, at temporary
offices, and at meetings. A notebook computer, sometimes called a laptop com-
puter, typically weighs less than five pounds and is three inches or less in thick-
ness.
Packet Filtering
- Discarding unwanted network traffic based on its originat-
ing address or range of addresses or its type (e-mail, file transfer, etc.).
Partitioning
- To divide a resource or application into smaller pieces.
PCI
(
P
eripheral
C
omponent
I
nterconnect) - A peripheral bus commonly used
in PCs, Macintoshes and workstations. It was designed primarily by Intel and
first appeared on PCs in late 1993. PCI provides a high-speed data path
between the CPU and peripheral devices (video, disk, network, etc.). There are
typically three or four PCI slots on the motherboard. In a Pentium PC, there is
generally a mix of PCI and ISA slots or PCI and EISA slots. Early on, the PCI
bus was known as a “local bus.”
PCI provides “plug-and-play” capability, automatically configuring the PCI
cards at startup. When PCI is used with the ISA bus, the only thing that is gen-
erally required is to indicate in the CMOS memory which IRQs are already in
use by ISA cards. PCI takes care of the rest.
PCI allows IRQs to be shared, which helps to solve the problem of limited IRQs
available on a PC. For example, if there were only one IRQ left over after ISA
devices were given their required IRQs, all PCI devices could share it. In a PCI-
only machine, there cannot be insufficient IRQs, as all can be shared.
PCMCIA
- The PCMCIA (Personal Computer Memory Card International
Association) is an industry group organized in 1989 to promote standards for a
credit card-size memory or I/O device that would fit into a personal computer,
usually a notebook or laptop computer.
Ping
(
P
acket
IN
ternet
G
roper) - An Internet utility used to determine whether
a particular IP address is online. It is used to test and debug a network by send-
ing out a packet and waiting for a response.
Plug-and-Play
- The ability of a computer system to configure expansion
boards and other devices automatically without requiring the user to turn off
the system during installation.
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