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ARP: Address Resolution Protocol. Protocol used to map an interface's IP address to the hardware address of the network card.

Daemon: A programme that runs in the background and performs a specific task. A Web server is usually implemented as a daemon.

Data Pipe: Daemon that accepts a TCP/IP connection from, and forwards it to, another host and port. Note that the host can be any host including the host on which the daemon is running.

DNS: Domain Name Service. Distributed database used to map host names to IP addresses and vice-versa.

Hardware Address: Unique number associated with each network card used with low level protocols.

Host: A computer on the Internet.

Localhost: Interface on a computer that loops back to the computer on which the interface resides on.

HTTP: HyperText Transfer Protocol. Protocol used by the World Wide Web.

IMAP: Internet Message Access Protocol. Protocol used to view mail in remote mail boxes.

Interface: Software access point to network hardware.

IP: Internet Protocol. The underlying protocol used to transfer data on the Internet.

IP Address: Unique number assigned to each interface on the Internet.

IP Aliasing: Kernel option that allows multiple interfaces to be assigned to a single network card.

ISP: Internet Services Provider. An organisation that provides internet connectivity and other related services.

LAN: Local Area Network. Network used to connect boxen at close proximity.

NFS: Network File System: Method of making a directory and its contents available to other boxen on a network. Redundancy: The ability to keep functioning at some level after a failure.

POP3: Post Office Protocol 3. Protocol used to download mail from remote mail boxes.

Proxy: A service by which requests for information from services such as HTTP are done on behalf of clients and the information is returned to the client. The information collected on behalf of the client, may be kept in a local cache, on the proxy server.

Port: A software access point to a host. Hosts have multiple ports and daemons typically listen on a specific port or ports for connections from clients.

Service: A source of information that users access. e.g. A HTTP server provides web pages.

SMTP: Simple Mail Transfer Protocol. Protocol used to transfer email over the internet.

SMTP relay: SMTP server that forwards email from one box to another.

TCP/IP: Transmission Control Protocol/Internet Protocol. Pair of protocols that provide a connection based service used on the internet for protocols such as HTTP and SMTP.

/etc/hosts: A file on unix systems that maps host name to IP addresses

next up previous contents
Next: Bibliography Up: Creating Redundant Linux Servers Previous: Discussion