Page 126 / 131 Scroll up to view Page 121 - 125
6381-A4 Router Users Guide
126
Broadband
A telecommunications technology that can send different types of data
over the same medium. DSL is a broadband technology.
Broadcast
To send data to all computers on a network.
DHCP
Dynamic Host Configuration Protocol
DHCP automates address assignment and management. When a
computer connects to the LAN, DHCP assigns it an IP address from a
shared pool of IP addresses; after a specified time limit, DHCP returns the
address to the pool.
DHCP relay
Dynamic Host Configuration Protocol relay
A DHCP relay is a computer that forwards DHCP data between
computers that request IP addresses and the DHCP server that assigns
the addresses. Each of the device’s interfaces can be configured as a
DHCP relay. See DHCP.
DHCP server
Dynamic Host Configuration Protocol server
A DHCP server is a computer that is responsible for assigning IP
addresses to the computers on a LAN. See DHCP.
Digital
Of data, having a form based on discrete values expressed as binary
numbers (0’s and 1’s). The data component in DSL is a digital signal. See
analog.
DNS
Domain Name System
The DNS maps domain names into IP addresses. DNS information is
distributed hierarchically throughout the Internet among computers called
DNS servers. For example, www.yahoo.com is the domain name
associated with IP address 216.115.108.243. When you start to access a
web site, a DNS server looks up the requested domain name to find its
corresponding IP address. If the DNS server cannot find the IP address, it
communicates with higher-level DNS servers to determine the IP address.
See domain name.
Domain name
A domain name is a user-friendly name used in place of its associated IP
address. Domain names must be unique; their assignment is controlled by
the Internet Corporation for Assigned Names and Numbers (ICANN).
Domain names are a key element of URLs, which identify a specific file at
a web site. See DNS.
Download
To transfer data in the downstream direction, i.e., from the Internet to the
user.
DSL
Digital Subscriber Line
A technology that allows both digital data and analog voice signals to
travel over existing copper telephone lines.
Encryption keys
See network keys
Ethernet
The most commonly installed computer network technology, usually using
twisted pair wiring. Ethernet data rates are 10 Mbps and 100 Mbps. See
also 10BASE-T, 100BASE-T, twisted pair.
Firewall
A firewall is protection between the Internet and your local network. It acts
as the firewall in your car does, protecting the interior of the car from the
engine. Your car's firewall has very small opening that allow desired
connections from the engine into the cabin (gas pedal connection, etc),
Page 127 / 131
6381-A4 Router Users Guide
127
but if something happens to your engine, you are protected.
The firewall in the router is very similar. Only the connections that you
allow are passed through the firewall. These connections normally
originate from the local network, such as users web browsing, checking e-
mail, downloading files, and playing games. However, you can allow
incoming connections so that you can run programs like a web server.
FTP
File Transfer Protocol
A program used to transfer files between computers connected to the
Internet. Common uses include uploading new or updated files to a web
server, and downloading files from a web server.
Gbps
Abbreviation of Gigabits per second, or one billion bits per second.
Internet data rates are often expressed in Gbps.
Host
A device (usually a computer) connected to a network.
HTTP
Hyper-Text Transfer Protocol
HTTP is the main protocol used to transfer data from web sites so that it
can be displayed by web browsers. See web browser, web site.
Hub
A hub is a place of convergence where data arrives from one or more
directions and is forwarded out in one or more directions. It connects an
Ethernet bridge/router to a group of PCs on a LAN and allows
communication to pass between the networked devices.
ICMP
Internet Control Message Protocol
An Internet protocol used to report errors and other network-related
information. The ping command makes use of ICMP.
IEEE
The Institute of Electrical and Electronics Engineers is a technical
professional society that fosters the development of standards that often
become national and international standards.
Internet
The global collection of interconnected networks used for both private and
business communications.
Intranet
A private, company-internal network that looks like part of the Internet
(users access information using web browsers), but is accessible only by
employees.
IP
See TCP/IP.
IP address
Internet Protocol address
The address of a host (computer) on the Internet, consisting of four
numbers, each from 0 to 255, separated by periods, e.g., 209.191.4.240.
An IP address consists of a network ID that identifies the particular
network the host belongs to, and a host ID uniquely identifying the host
itself on that network. A network mask is used to define the network ID
and the host ID. Because IP addresses are difficult to remember, they
usually have an associated domain name that can be specified instead.
See domain name, network mask.
ISP
Internet Service Provider
A company that provides Internet access to its customers, usually for a
fee.
Page 128 / 131
6381-A4 Router Users Guide
128
LAN
Local Area Network.
A network limited to a small geographic area, such as a home or small
office.
LED
Light Emitting Diode
An electronic light-emitting device. The indicator lights on the front of the
device are LEDs.
MAC address
Media Access Control address
The permanent hardware address of a device, assigned by its
manufacturer. MAC addresses are expressed as six pairs of hex
characters, with each pair separated by colons. For example;
NN:NN:NN:NN:NN:NN.
Mask
See network mask.
Mbps
Abbreviation for Megabits per second, or one million bits per second.
Network data rates are often expressed in Mbps.
NAT
Network Address Translation
A service performed by many routers that translates your network’s
publicly known IP address into a private IP address for each computer on
your LAN. Only your router and your LAN know these addresses; the
outside world sees only the public IP address when talking to a computer
on your LAN.
Network
A group of computers that are connected together, allowing them to
communicate with each other and share resources, such as software,
files, etc. A network can be small, such as a LAN, or very large, such as
the Internet.
Network keys
(Also known as encryption keys.) 64-bit and 128-bit encryption keys used
in WEP wireless security schemes. The keys encrypt data over the
WLAN, and only wireless PCs configured with WEP keys that correspond
to the keys configured on the device can send/receive encrypted data.
Network mask
A network mask is a sequence of bits applied to an IP address to select
the network ID while ignoring the host ID. Bits set to 1 mean “select this
bit” while bits set to 0 mean “ignore this bit.” For example, if the network
mask 255.255.255.0 is applied to the IP address 100.10.50.1, the network
ID is 100.10.50, and the host ID is 1. See binary, IP address, subnet.
NIC
Network Interface Card
An adapter card that plugs into your computer and provides the physical
interface to your network cabling. For Ethernet NICs this is typically an
RJ-45 connector. See Ethernet, RJ-45.
Packet
Data transmitted on a network consists of units called packets. Each
packet contains a payload (the data), plus overhead information such as
where it came from (source address) and where it should go (destination
address).
Ping
Packet Internet (or Inter-Network) Groper
A program used to verify whether the host associated with an IP address
is online. It can also be used to reveal the IP address for a given domain
name.
Port
A physical access point to a device such as a computer or router, through
which data flows into and out of the device.
Page 129 / 131
6381-A4 Router Users Guide
129
PPP
Point-to-Point Protocol
A protocol for serial data transmission that is used to carry IP (and other
protocol) data between your ISP and your computer. The WAN interface
on the device uses two forms of PPP called PPPoA and PPPoE. See
PPPoA, PPPoE.
PPPoA
Point-to-Point Protocol over ATM
One of the two types of PPP interfaces you can define for a Virtual Circuit
(VC), the other type being PPPoE. You can define only one PPPoA
interface per VC.
PPPoE
Point-to-Point Protocol over Ethernet
One of the two types of PPP interfaces you can define for a Virtual Circuit
(VC), the other type being PPPoA. You can define one or more PPPoE
interfaces per VC.
Protocol
A set of rules governing the transmission of data. In order for a data
transmission to work, both ends of the connection have to follow the rules
of the protocol.
Remote
In a physically separate location. For example, an employee away on
travel who logs in to the company’s intranet is a remote user.
RIP
Routing Information Protocol
The original TCP/IP routing protocol. There are two versions of RIP:
version I and version II.
RJ-11
Registered Jack Standard-11
The standard plug used to connect telephones, fax machines, modems,
etc. to a telephone port. It is a 6-pin connector usually containing four
wires.
RJ-45
Registered Jack Standard-45
The 8-pin plug used in transmitting data over phone lines. Ethernet
cabling usually uses this type of connector.
Routing
Forwarding data between your network and the Internet on the most
efficient route, based on the data’s destination IP address and current
network conditions. A device that performs routing is called a router.
SDNS
Secondary Domain Name System (server)
A DNS server that can be used if the primary DSN server is not available.
See DNS.
Subnet
A subnet is a portion of a network. The subnet is distinguished from the
larger network by a subnet mask that selects some of the computers of
the network and excludes all others. The subnet’s computers remain
physically connected to the rest of the parent network, but they are
treated as though they were on a separate network. See network mask.
Subnet mask
A mask that defines a subnet. See network mask.
TCP
See TCP/IP.
TCP/IP
Transmission Control Protocol/Internet Protocol
The basic protocols used on the Internet. TCP is responsible for dividing
data up into packets for delivery and reassembling them at the
destination, while IP is responsible for delivering the packets from source
to destination. When TCP and IP are bundled with higher-level
applications such as HTTP, FTP, Telnet, etc., TCP/IP refers to this whole
Page 130 / 131
6381-A4 Router Users Guide
130
suite of protocols.
Telnet
An interactive, character-based program used to access a remote
computer. While HTTP (the web protocol) and FTP only allow you to
download files from a remote computer, Telnet allows you to log into and
use a computer from a remote location.
TFTP
Trivial File Transfer Protocol
A protocol for file transfers, TFTP is easier to use than File Transfer
Protocol (FTP) but not as capable or secure.
TKIP
Temporal Key Integrity Protocol (TKIP) provides WPA with a data
encryption function. It ensures that a unique master key is generated for
each packet, supports message integrity and sequencing rules and
supports re-keying mechanisms.
Triggers
Triggers are used to deal with application protocols that create separate
sessions. Some applications, such as NetMeeting, open secondary
connections during normal operations, for example, a connection to a
server is established using one port, but data transfers are performed on
a separate connection. A trigger tells the device to expect these
secondary sessions and how to handle them.
Once you set a trigger, the embedded IP address of each incoming
packet is replaced by the correct host address so that NAT can translate
packets to the correct destination. You can specify whether you want to
carry out address replacement, and if so, whether to replace addresses
on TCP packets only, UDP packets only, or both.
Twisted pair
The ordinary copper telephone wiring used by telephone companies. It
contains one or more wire pairs twisted together to reduce inductance and
noise. Each telephone line uses one pair. In homes, it is most often
installed with two pairs. For Ethernet LANs, a higher grade called
Category 3 (CAT 3) is used for 10BASE-T networks, and an even higher
grade called Category 5 (CAT 5) is used for 100BASE-T networks. See
10BASE-T, 100BASE-T, Ethernet.
Unnumbered interfaces
An unnumbered interface is an IP interface that does not have a local
subnet associated with it. Instead, it uses a router-id that serves as the
source and destination address of packets sent to and from the router.
Unlike the IP address of a normal interface, the router-id of an
unnumbered interface is allowed to be the same as the IP address of
another interface. For example, the WAN unnumbered interface of your
device uses the same IP address of the LAN interface (192.168.1.1).
The unnumbered interface is temporary – PPP or DHCP will assign a
‘real’ IP address automatically.
Upstream
The direction of data transmission from the user to the Internet.
VC
Virtual Circuit
A connection from your DSL router to your ISP.
VCI
Virtual Circuit Identifier
Together with the Virtual Path Identifier (VPI), the VCI uniquely identifies a
VC. Your ISP will tell you the VCI for each VC they provide. See VC.
VDSL
Very High Speed Digital Subscriber Line
It provides faster transmission rate and is capable of supporting high
bandwidth applications like IPTV and bandwidth consumed applications.

Rate

3.7 / 5 based on 3 votes.

Bookmark Our Site

Press Ctrl + D to add this site to your favorites!

Share
Top