Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

ADSL
Asymmetrical Digital Subscriber Line – A member of the broadband Internet connection family, has variable download and upload capacity. The connection benefits from high speeds, always connected, contention ratios of 50-1 or 20-1. ADSL needs to be activated on a BT telephone line, within recommended distance of a enabled BT exchange.

Application server
Server software that manages one or more other pieces of software in a way that makes the managed software available over a network, usually to a Web server. By having a piece of software manage other software packages it is possible to use resources like memory and database access more efficiently than if each of the managed packages responded directly to requests.

Bandwidth
How much traffic you can send through a connection. Usually measured in bits-per-second (bps).

bps
Bits-Per-Second – A measurement of how fast data is moved from one place to another. A 56K modem can move about 57,000 bits-per-second.

Byte
A set of Bits that represent a single character. Usually there are 8 Bits in a Byte.

cgi-bin
The most common name of a directory on a web server in which CGI programs are stored. CGI is a set of rules for running scripts or programs on a Web server. When you submit information, like search terms or your username and password, to a Web server, there’s a good chance that the server is using a CGI script to receive and process the data.

Co-location
Co-location is a type of hosting where the customer’s server equipment is hosted in Datanet’s data centre. Datanet will be responsible for providing power and connectivity, IP addresses and support for your server.

Contention ratio
Contention ratio referred to in the same context as broadband means that the network bandwidth available is shared between a number of subscribers. i.e. contention ratio of 50:1 is shared between up to 50 subscribers.

Dedicated servers
A supply of a server by Datanet for the purpose of storing data. Servers are housed in our Datacentres and benefit from Service Level Agreements (SLAs).

Dial-up
A pay as you go Internet access service that requires input of login details every time you wish to connect.

Domain names
This is the name that typically identifies a website. For example, “datanet.co.uk” is the domain name of Datanet’s website. Then there are domain names that have been registered, but are not connected to a Web server. The most common reason for this is to have email addresses at a certain domain name without having to maintain a website.

Ethernet
A very common method of networking computers in a LAN, MAN or WAN.

Firewalls
A device that blocks unwanted access to a LAN or other network.

FTP
File Transfer Protocol – very common method of moving files between two Internet sites. FTP is a way to login to another Internet site for the purposes of retrieving and/or sending files.

Gateway server
Allows two or more network users to share a single email account via a modem or ISDN terminal adapter.

HTTP
Hypertext Transfer Protocol – The protocol for moving hypertext files across the Internet. Requires a HTTP client program on one end, and an HTTP server program (such as Apache) on the other end. HTTP is the most important protocol used in the World Wide Web (WWW).

Hub/switch
This is a hardware device that is used to network multiple computers together. It is a central connection for all the computers in a network, which is usually Ethernet-based. Information sent to the hub can flow to any other computer on the network.

Intranet
A private network inside a company or organisation that uses the same kind of software that you would find on the public Internet, but that is only for internal use.

IP address
A unique 32-bit number that identifies the location of your computer on a network. Basically, it works like your street address — as a way to find out exactly where you are and deliver information to you.

ISP
Internet Service Provider – A business that provides access to the Internet in various forms.

Jitter
Jitter is the variation in the time between packets arriving, caused by network congestion, timing drift, or route changes. A jitter is normally quoted when circuits will be used for VoIP applications.

LAN
Local Area Network, office based network.

Latency
This is the amount of time it takes a packet of data to move across a network connection. When a packet is being sent, there is “latent” time, when the computer that sent the packet waits for confirmation that the packet has been received. Latency and bandwidth are the two factors that determine your network connection speed.

Leased Line
A leased line is a (usually) symmetric telecommunications line connecting two locations together. Unlike traditional PSTN lines they do not have a telephone number, each side of the line being permanently connected to the other. They can be used for telephone, data or Internet services.

Linux
A widely used Open Source Unix-like operating system. Linux was first released by its inventor Linus Torvalds in 1991.

MAC code
MAC stands for Migration Authorisation Code. It is issued by your broadband provider and is used to seamlessly switch from one provider to another without having to wait weeks to cease your line and re-register with another provider. The number usually starts with BBIP – a unique identifier number.

Mail Gate
Email software that helps improve email management through a convenient web console that is capable of providing real time monitoring and alerting, as well as comprehensive reporting for system administrators.

MessageScreen
A Datanet anti-virus/anti-spam service that filters spam from your email and quarantines viruses before they reach your inbox.

Meta Tag
A specific kind of HTML tag that contains information not normally displayed to the user. Meta tags contain information about the page itself, hence the name (“meta” means “about this subject”). Typical uses of Meta tags are to include information for search engines to help them better categorise a page. You can see the Meta tags in a page if you view the pages’ source code.

MPLS – Multi Protocol Label Switching
MPLS gives network operators a great deal of flexibility to divert and route traffic around link failures, congestion, and bottlenecks. ISPs will better be able to manage different kinds of data streams based on priority and service plan. For instance, those who subscribe to a premium service plan, or those who receive a lot of streaming media or high-bandwidth content can see minimal latency.

NAT
Network Address Translation. Used to reduce the number of IP addresses required. Allows a single device, such as a router, to act as an agent between the Internet (or “public network”) and a local (or “private”) network. This means that only a single, unique IP address is required to represent an entire group of computers.

POP
Point of Presence usually means a location where a network can be connected to Datanet’s POP is used in context with our datacentres.

Protocol
On the Internet “protocol” usually refers to a set of rules that define an exact format for communication between systems. For example the HTTP protocol defines the format for communication between web browsers and web servers.

Router
A device used for multiple users. Routers spend all their time looking at the source and destination addresses of the packets passing through them and deciding which route to send them on.

SDSL
Symmetrical Digital Subscriber line – A member of the broadband Internet connection family, has the same download capacity as upload capacity. The connection benefits from high speeds, always connected, contention ratio of 10:1. SDSL needs to be activated on a dedicated telephone line installed solely for the purpose of SDSL. The dedicated line is known as a MPF metallic path.

SLAs
Service Level Agreements – A document supplied to explain core guarantees of service, methods of dealing with operational problems and standards of service.

SMTP
Simple Mail Transfer Protocol – is the main protocol used to send electronic mail from server to server on the Internet.

USB modem
A device that is attached to a PC through a USB port. Ideal for a single user to access the Internet. Only active when computer switched on/Internet function activated.

VoIP
Voice over IP is the routing of voice conversations over the Internet or Internet based network.

VPN
Virtual Private Network – System whereby data can be sent securely over the Internet (through encryption). Links different offices and home users into one central system.

Web hosting
Web hosting is where we allocate an agreed amount of space on our servers for you to store your website. We can offer 100MB to 1GB depending on how big your website is.

Call our team today on 01252 810010 to find out more about how we can help you