WIDE AREA NETWORK

Alliance Datacom offers WAN design, network solutions, and is an WAN equipment supplier. Call today for questions or help designing or building your Wide Area Network.

A WAN is a data communications network that covers a relatively broad geographic area and often uses transmission facilities provided by common carriers, such as telephone companies. WAN technologies function at the lower three layers of the OSI reference model: the physical layer, the data link layer, and the network layer.

A point-to-point link provides a single, preestablished WAN communications path from the customer premises through a carrier network, such as a telephone company, to a remote network. A point-to-point link is also known as a leased line because its established path is permanent and fixed for each remote network reached through the carrier facilities. The carrier company reserves point-to-point links for the private use of the customer. These links accommodate two types of transmissions: datagram transmissions, which are composed of individually addressed frames, and data-stream transmissions, which are composed of a stream of data for which address checking occurs only once.

Circuit switching is a WAN switching method in which a dedicated physical circuit is established, maintained, and terminated through a carrier network for each communication session. Circuit switching accommodates two types of transmissions: datagram transmissions and data-stream transmissions. Used extensively in telephone company networks, circuit switching operates much like a normal telephone call.

Packet switching is a WAN switching method in which network devices share a single point-to-point link to transport packets from a source to a destination across a carrier network. Statistical multiplexing is used to enable devices to share these circuits. Asynchronous Transfer Mode (ATM), Frame Relay, Switched Multimegabit Data Service (SMDS), and X.25 are examples of packet-switched WAN technologies.

• Private IP Networking
  Want to save time, money and hassle in administering your complex network? Consider replacing your frame relay and ATM-based WAN with a private IP service.
• Internet Core Protocols
  Take control of your IP network with our guide to the Internet Control Message Protocol. In this excerpt from his book Internet Core Protocols, Eric A. Hall explains how to get the most out of ICMP tools.
• IP Tutorial: Basic Addressing
  The Internet Protocol (IP) had its origins in UNIX? networking as it developed in the 1970s. Today, IP has become a standard mechanism for network operating systems (NOS) to communicate with each other. Well-known protocols such as HTTP and TCP have been built on top of the IP foundation.