Glossary | Apple AirPort Networks guide

roaming (Wi-Fi)The ability to move from one area of Wi-Fi coverage to another with no loss in connectivity (hand-off).

router A wireless router is a device that accepts connections from wireless devices to a network, includes a network firewall for security, and provides local network addresses. See hub.

server A computer that provides resources or services to other computers and devices on a network. Types of servers include print servers, Internet servers, mail servers, and DHCP servers. A server can also be combined with a hub or router. See DHCP, hub, router.

SSID Service set identifier. A unique 32-character network name, or identifier, that differentiates one wireless LAN from another. All access points and clients attempting to connect to a specific WLAN must use the same SSID. The SSID can be any alphanumeric entry up to a maximum of 32 characters. See network name.

subnet An IP address range that is part of a larger address range. Subnets are used to subdivide a network address of a larger network into smaller networks. Subnets connect to other networks through a router. Each individual wireless LAN will typically use the same subnet for all of its clients. See IP address, router.

TCP Transmission Control Protocol. The transport-level protocol used with the Internet Protocol (IP) to route data across the Internet. See IP, TCP/IP.

TCP/IP The underlying technology of Internet communications. While IP handles the actual delivery of data, TCP tracks the data packets to efficiently route a message through the Internet. Every computer in a TCP/IP network has its own IP address that is either dynamically assigned at startup (see DHCP) or permanently assigned as a static address. All TCP/IP messages contain the address of the destination network, as well as the address of the destination station. This enables TCP/IP messages to be transmitted to multiple networks (subnets) within an organization or worldwide. For example, when a user downloads a webpage, TCP divides the page file on the web server into packets, numbers the packets, and forwards them individually to the user’s IP address. The packets may be routed along different paths before reaching the user’s address. At the destination, TCP reassembles the individual packets, waiting until they have all arrived to present them as a single file. See IP, IP address, packet, TCP.

throughput Usually measured in bps, Kbps, Mbps or Gbps, throughput is the amount of data that can be sent from one location to another in a specific amount of time. See bps, Mbps.

USB Universal Serial Bus. A high-speed bidirectional serial connection used to transfer data between a computer and peripherals such as digital cameras and memory cards.