How do wide area networks work

At work or school, the LAN might connect devices over hundreds of metres. Figure 1. Activity Do you know who your ISP is? How much do they charge for Internet access?

Figure 2. Figure 3. Figure 4. Cable systems have now grown in popularity as a means of distributing a wide number of television channels to users within cities without the need for individual homes to have external antenna systems. A wide area network also known as WAN , is a large network of information that is not tied to a single location. WANs can facilitate communication, the sharing of information and much more between devices from around the world through a WAN provider.

WANs can be vital for international businesses, but they are also essential for everyday use, as the internet is considered the largest WAN in the world. Keep reading for more information on WANs, their use, how they differ from other networks and their overall purpose for businesses and people, alike.

As described above, wide area networks are a form of telecommunication networks that can connect devices from multiple locations and across the globe. WANs are the largest and most expansive forms of computer networks available to date. These networks are often established by service providers that then lease their WAN to businesses, schools, governments or the public. These customers can use the network to relay and store data or communicate with other users, no matter their location, as long as they have access to the established WAN.

Access can be granted via different links, such as virtual private networks VPNs or lines, wireless networks, cellular networks or internet access. For international organizations, WANs allow them to carry out their essential daily functions without delay. Router is connected to the LAN at one side and a hub is attached at the other end. A circuit switching network is established when at the one end a node and on the other end a terminal is physically connected to each other for further communication.

The most common physical network nodes are switches, hub and a modem. Whereas a terminal is a physical device that does the basic communication, for example like a telephone, call answering machine or a printer sometimes.

The data travels through the use of network protocols. The protocols are the defined rules which guide the information transfer. The purpose of protocols is to detect the errors. Traffic can be shaped to give time-sensitive applications such as VoIP a higher priority over other, less urgent traffic such as email, which in turn helps improve the overall WAN performance.

This can be formalized into quality-of-service settings that define classes of traffic by the priority each class receives relative to others, the type of WAN connection that each traffic type will travel, and the bandwidth that each receives. WANs have been around since the early days of computing networks. WANs were based on circuit-switched telephone lines and modems but now connectivity options also include leased lines, wireless, MPLS, broadband internet, and satellite.

As technologies changed, so did transmission rates. The early days of bps modems evolved to 40Gbps and Gbps connectivity today. These speed increases have allowed more devices to connect to networks, enabling the explosion of connected computers, phones, tablets and smaller Internet of Things devices.

In addition, speed improvements have allowed applications to utilize larger amounts of bandwidth that can travel across WANs at super-high speed. This has allowed enterprises to implement applications such as videoconferencing and large-file data backup. Nobody would have considered conducting a videoconference across a 28kbps modem, but now workers can sit at home and participate in global company meetings via video.

These are typically used for top-priority or delay-sensitive applications that have high-bandwidth needs such as videoconferencing. Traffic between WAN sites may be protected by virtual private networks VPN that overlay security on the underlying physical network, including authentication, encryption, confidentiality and non-repudiation.

In general, security is a crucial part of any WAN rollout, because a WAN connection represents a potential vulnerability that an attacker could use to gain access to a private network. For instance, a branch office without a full-time infosec staffer might be lax in its cybersecurity practices. As a result, a hacker who breached the network at the branch could go on to access the main corporate WAN, including valuable assets that would have been otherwise impregnable.

In addition to networking features, many SD-WAN offerings provide security services as well, which need to be kept top of mind during deployment. The Disruption Tolerant Networking DTN program is the first step in providing an Internet-like structure for communications between space-based devices, including communicating between the Earth and Moon, or other planets.

But barring any dramatic breakthrous in physics, network speeds would likely top out at the speed of light.