Leased Line Glossary
ATM – Asynchronous Transfer Mode is an International Telecommunication Union-Telecommunications Standards Section (ITU-T) standard for cell relay wherein information for multiple service types, such as voice, video, or data, is conveyed in small, fixed-size cells.
ETHERNET – Ethernet is the most widely-installed local area network (LAN) technology. It is a local-area network (LAN) architecture developed by Xerox Corporation in cooperation with DEC and Intel in 1976. Ethernet uses a bus or star topology and supports data transfer rates of 10 Mbps.
IP – The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. It specifies the format of packets, also called datagrams, and the addressing scheme. Most networks combine IP with a higher-level protocol called Transmission Control Protocol (TCP), which establishes a virtual connection between a destination and a source. IP by itself is something like the postal system. It allows you to address a package and drop it in the system, but there is no direct link between you and the recipient.
ISP – Internet Service Provider is a company that provides access to the Internet.
INTERNET BACKBONE – this refers to the public internet.
LAN – Local Area Network is a group of computers and associated devices that share a common communications line or wireless link and typically share the resources of a single processor or server within a small geographic area (for example, within an office building). Usually, the server has applications and data storage that are shared in common by multiple computer users. A local area network may serve as few as two or three users (for example, in a home network) or as many as thousands of users (for example, in an FDDI network).
POP – A Point of Presence is an access point to a service provider’s or a carrier’s network. It might be where they access the Internet and connect to their upstream or backbone provider. It might also be a strategically located aggregation point that serves business hotspots. A Point of Presence is typically rented rackspace within a datacentre or a ‘Telehouse’ used to terminate local loops before backhauling them to their destination.
QUALITY OF SERVICE (QOS) – on the Internet and in other networks, QoS (Quality of Service) is the idea that transmission rates, error rates, and other characteristics can be measured, improved, and, to some extent, guaranteed in advance. QoS is of particular concern for the continuous transmission of high-bandwidth video and multimedia information. Transmitting this kind of content dependably is difficult in public networks using ordinary “best effort” protocols.
ROUTER – A router is a device or, in some cases, software in a computer, that determines the next network point to which a packet should be forwarded toward its destination. The router is connected to at least two networks and decides which way to send each packet based on its current understanding of the state of the networks it is connected to.
SDH – (Synchronous Digital Hierarchy) is a standard technology for synchronous data transmission on optical media. It is the international equivalent of Synchronous Optical Network. Both technologies provide faster and less expensive network interconnection than traditional PDH (Plesiochronous Digital Hierarchy) equipment.
SLA – Service Level Agreement is a contract between a network service provider and a customer that specifies, in measurable terms, what services are provided. Many ISPs provide their customers with an SLA.