Glossary
Converged Network
A single network with the capacity to carry a combination of
data, voice and video traffic
End Devices
A device that a person can use for
communication purposes – for example - a desktop computer,
cell phone, PDA, laptop etc
Firewall
A firewall prevents unauthorized access to or
from a private network. A firewall can be installed either
via hardware or software or a combination of both and it is
designed to prevent and filter unauthorised access via the internet
to a private network.
Hub
A hub is a multi-port repeater. Whatever
signal is received at one interface of the hub is repeated out all
the other interfaces of the hub. Hubs vary in terms of the number
of ports and management issues. For security, control, and
performance reasons, most organizations have replaced hubs with
switches.
IP Address
An identification number for a computer or
device on a TCP/IP network. Networks which use the TCP/IP protocol
determine the destination of a message based on the IP address.
LAN
A local area network, where computers are
geographically close together (in the same office, building)
Network
A group of two or more computer systems linked
together in order to share information and resources. There
are two main categories of computer networks: LAN and WAN
Peer –to-Peer Network
In a peer-to-peer network, all workstations
share their resources, including internal hard drives and printers,
with all other workstations on the LAN. Each computer must share
its resources with the other computers on the LAN, which can slow
the response time to the local user, as the resources may be busy
supporting external users.
QoS
Quality of Service is the ability to control
the characteristics of ongoing communication services.
Service providers use these control values to offer improved and
possibly contract levels of service. QoS is an end-to-end
responsibility that involves clients, switches, routers, and
servers
Router
A router is an internetworking device commonly
used to connect different network types together. A router is
custom configured for the various networks that an organization
supports (LANs and WANs). Routers use software addressing systems,
such as IP addressing, to logically address data, allowing a packet
of data to be addressed and carried through several different layer
2 networks.
Routing Protocols
The routing protocol is the code configured
and running on
routers.
RIP Routing
Information Protocol
OSPF Open Shortest Path
First
IGRP Interior
Gateway Routing Protocol
EIGRP Enhanced Interior Gateway
Routing Protocol
BGP Border
Gateway Protocol
IS-IS
Intermediate System-to-Intermediate System
Subnetting
Subnetting divides a network into several
subnetworks (or subnets). All systems (for example, workstations,
printers, server, and routers) that exist in the subnet have common
network and subnet values, but each must have a unique interface
portion of their logical or IP address.
Switching
A technology that offers a fast and easy way
to physically isolate segment network traffic for performance and
security reasons. Switches improve security by sending traffic only
to the addressed device. Many organizations use switches to
replace hubs to connect and now use switches as their intermediate
device of choice replacing almost all hubs and most routers.
Video over IP
New video-compression capabilities like MPEG4
claim to squeeze current commercial, high quality video into DSL
friendly range of about 1 Mbps. Combining this with 10Gbps
Ethernet opens the ability for each user to have access to a huge
catalogue of on-demand video offerings. The focus of
converging voice and data will now add video to the mix. The
next generation network providers will function as an information
utility company, which will make the shift from telecommunications
to combined infrastructure, service providing and content offering
organizations.
VoIP
Individuals inside and outside organizations
can contact their friends, coworkers, and customers using VOIP
(Voice Over Internet Protocol) capabilities everywhere that an IP
network reaches. Current network capabilities may be
sufficient to use VOIP if enough bandwidth is available to carry
the voice traffic. Companies are now looking at a VoIP
network to combine both the voice network (traditional telephone)
and data network into one common network for all communication
VPN
A VPN is a form of communication over networks
that are public in ownership, but emulate a private network in
terms of security.
WAN
A wide area network which connects LANs to
each other and offers the means to provide services and resources
in multiple locations. Most organizations rely on service providers
for their WANs.
WiMAX
WiMAx is the new wireless broadband with a
range of up to 80km, with a bandwith of up to 75bps. It
is the successor to Wi-Fi.
Wireless Networks
There are three basic methods to create a
wireless network – infrared, radio or laser. Infrared for
local wire replacements over small distances (mouse to PC).
Laser technology offers much greater capability for distance and
speed. In networking, lasers typically bridge two network segments
between two separate buildings. Radio solutions are different
for LAN and WAN use. WANs use satellite and microwave portions of
the radio frequency spectrum. LANs use radios that operate in the
free use frequency ranges of the 2.4 GHz ISM