In place of cable connectivity and DSL, many users are now opting for wireless connectivity.
The reach of wireless connections now includes personal area networks, LANs, and WANs. The number of hotspots has increased access to wireless connections across the world. A hotspot is the area covered by one or more interconnected access points. Public gathering places, like coffee shops, cafes, and libraries, have Wi-Fi hotspots. By overlapping access points, hotspots can cover many square miles.
Developments in broadband wireless technology are increasing wireless availability. These broadband types are explained in Figure 1 and include:
- Municipal Wi-Fi (Mesh)
- WiMAX (Worldwide Interoperability for Microwave Access)
- Cellular/mobile
- Satellite Internet
Municipal Wi-Fi
Many municipal governments, often working with service providers, are deploying wireless networks. Some of these networks provide high-speed Internet access at no cost or for substantially less than the price of other broadband services. Other cities reserve their Wi-Fi networks for official use, providing police, fire fighters, and city workers remote access to the Internet and municipal networks.
Most municipal wireless networks use a mesh topology rather than a hub-and-spoke model. A mesh is a series of interconnected access points as shown in Figure 2. Each access point is in range and can communicate with at least two other access points. The mesh blankets its area with radio signals. Signals travel from access point to access point through this cloud.
A meshed network has several advantages over a singular wireless router hotspot. Installation is easier and can be less expensive because there are fewer wires. Deployment over a large urban area is faster and more reliable. If a node fails, others in the mesh compensate for it.
WiMAX
WiMAX, as shown in Figure 3, is a telecommunications technology aimed at providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access. WiMAX operates at higher speeds, over greater distances, and for a greater number of users than Wi-Fi. Because of its higher speed (bandwidth) and falling component prices, it is predicted that WiMAX will soon supplant municipal mesh networks for wireless deployments.
A WiMAX network consists of two main components:
- A tower that is similar in concept to a cellular telephone tower. A single WiMAX tower can provide coverage to an area as large as 3,000 square miles (7,500 square km).
- A WiMAX receiver that is connected to a USB port or is built into a laptop or other wireless device.
A WiMAX tower station connects directly to the Internet using a high-bandwidth connection, such as a T3 line. A tower can also connect to other WiMAX towers using line-of-sight microwave links. WiMAX is thus able to provide coverage to rural areas out of reach of last mile cable and DSL technologies.