FITS Release Management
© Becta 2004
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A system designed to prevent unauthorised access to or from a private network.
Firewalls can be implemented in both hardware and software, or a combination of
both. Firewalls are frequently used to prevent unauthorised internet users from
accessing private networks connected to the internet, especially intranets. All
messages entering or leaving the intranet pass through the firewall, which examines
each message and blocks those that do not meet the specified security criteria.
Firewall
A node on a network that serves as an entrance to another network. In schools, the
gateway is the computer that routes the traffic from a workstation to the outside
network that is serving web pages. In homes, the gateway is the ISP that connects
the user to the internet.
Gateway
When used to describe data transfer rates, it refers to 10 to the 9th power
(1,000,000,000) bits. Gigabit is abbreviated Gb, as opposed to gigabyte, which is
abbreviated GB.
Gigabit
The underlying protocol used by the World Wide Web. HTTP defines how messages
are formatted and transmitted, and what actions web servers and browsers should
take in response to various commands. For example, when you enter a URL in your
browser, this actually sends an HTTP command to the web server directing it to
fetch and transmit the requested web page.
HTTP
(hypertext
transfer protocol)
A connection point for devices in a network. Hubs are commonly used to connect
segments of a LAN (local area network). A hub contains multiple ports. When a
packet arrives at one port, it is copied to the other ports so that all segments of the
LAN can see all packets.
Hub
The convergence of information technology, telecommunications and data
networking technologies into a single technology.
ICT
Any event which is not part of the standard operation of a service and which causes,
or may cause, an interruption to, or a reduction in, the quality of that service.
Incident
To detect, diagnose and resolve ICT incidents as quickly as possible and minimise
their adverse impact on normal operation.
Incident
Management
The OGC IT Infrastructure Library – a set of guides on the management and
provision of operational IT services.
ITIL
A computer network that spans a relatively small area. Most local area networks
(LANs) are confined to a single building or group of buildings.
LAN
The cabling scheme supported by the AppleTalk network protocol for Macintosh
computers. Most local area networks that use AppleTalk, such as TOPS, also conform
to the LocalTalk cable system. Such networks are sometimes called LocalTalk
networks.
LocalTalk
The logical topology is the way that the signals act on the network media, or the
way that the data passes through the network from one device to the next without
regard to the physical interconnection of the devices.
Logical topology
Each device on a network can be identified by its MAC address, a hardware address
that uniquely identifies each node of a network. In IEEE 802 networks, the data link
control (DLC) layer of the OSI reference model is divided into two sub-layers: the
logical link control (LLC) layer and the MAC layer. The MAC layer interfaces directly
with the network media. Consequently, each different type of network media
requires a different MAC layer.
MAC (media
access control)
address