NETWORK FUNDAMENTALS

A network device that accesses a service on another computer remotely by accessing the network.

A network device, typically connected to a range of LAN and WAN interfaces, that forwards packets based on their destination IP addresses.

A company that helps create the Internet by providing connectivity to enterprises and individuals, as well as interconnecting to other ISPs to create connectivity to all other ISPs.

Written specifications that define what tasks a service or device should perform. Each protocol defines messages, often in the form of headers, plus the rules and processes by which these messages are used to achieve some stated purpose.

The Layer 2 PDU that has been encoded by a data link layer protocol for digital transmission. Some different kinds of frames are Ethernet frames and PPP frames.

The network that combines enterprise networks, individual users, and ISP's into a single global IP network.

Technology that allows communication without needing physical connectivity. Examples of wireless technology include cellular telephones, personal digital assistants (PDA), wireless access points, and wireless NICs.

When used generically, this term refers to end-user data along with networking headers and trailers that are transmitted through a network. When used specifically, it is end-user data, along with the network or Internet layer headers and any higher-layer headers, but no lower-layer headers or trailers.

The design on networks that can continue to operate without interruption in the case of hardware, software, or communications failures

A data link layer address, for example, a MAC address.

IPv4 address of a network host. When talking about host addresses, they are the network layer addresses.

In networking, this term is used in several ways. With Ethernet hub and switch hardware, port is simply another name for interface, which is a physical connector in the switch into which a cable can be connected. With TCP and UDP, a port is a software function that uniquely identifies a software process on a computer that uses TCP or UDP. With PCs, a port can be a physical connector on the PC, like a parallel or USB port.

A control mechanism that can provide different priorities to different users or data flows, or guarantee a certain level of performance to a data flow in accordance with requests from the application program.

A network created for devices located in a limited geographic area, through which the company owning the LAN has the right to run cables.

A process where multiple digital data streams are combined into one signal.