What Is Outdoor Point-to-Point Wireless?

A point-to-point (p-t-p) connection connects two LANs at different sites or buildings. A point-to-multipoint connection connects many LANs at various sites back to a central location.

Think of wireless outdoor links as extensions to your traditional wired network. Wireless links simply take the place of a cabled, dial-up or other telecommunications link traditionally used to connect remote sites back to a central office. They can also serve to extend your LAN quickly and easily to another building close by.

Wireless links use a transmission medium, just like wired LANs. Instead of using twisted-pair or fiber-optic cable, wireless links use either infrared light (IR) or radio frequencies (RF).

Wireless networking is used to connect disparate networks in different locations making access easier and more cost effective. Point-to-point and point-to-multipoint connections allow users in different locations the opportunity to access the Internet, share files and access network resources without wires.

Why Outdoor Wireless?

Wireless links are less costly than leased telecommunications lines and can connect sites separated by obstacles that make cabling difficult or impossible (eg - waterways, freeways, etc). Wireless connections can carry data or voice or both, and a variety of throughput rates are available, up to 1 GB.

Outdoor wireless will benefit any company that needs the flexibility and cost savings offered by a line-of-sight, building-to-building bridge to avoid expensive trenches or payment of recurring leased line fees.

When bridging between buildings with traditional copper or fiber-optic cable, roads, freeways, lakes, and even local governments can become impassible obstacles. A wireless bridge makes these obstacles irrelevant, transmitting data through the air and requiring no license or right of way.

Without a wireless alternative, organizations frequently resort to wide area networking (WAN) technologies to link together separate LANs. Contracting with a local telecommunications provider for a leased line presents some drawbacks - installation is typically expensive and rarely immediate, monthly fees are often quite high for bandwidth that by LAN standards is very low. A wireless bridge can be purchased and then installed in an afternoon for a cost that is often comparable to a leased line installation charge alone. Once the investment is made, there are no recurring charges, and today's wireless bridges provide the bandwidth one would expect from a LAN technology embedded in data, rather than voice, communications.

How does it work?

Wireless links use electromagnetic airwaves (radio or infrared) to communicate information from one point to another without relying on any physical connection.

For a point-to-point link, a wireless bridge and often an external antenna are positioned on a building at each site. Each wireless bridge is connected to the LAN within the building, and network data is transmitted via the antenna to the other site. Most technologies using wireless transmission for outdoor communication require a direct line-of-sight between the two antennae, with no obstacles in between.

A point-to-multipoint configuration works in a similar way, with a wireless bridge and external antenna at each site. Each wireless bridge is connected to its LAN and data is transmitted via the antenna to the other site(s). Most wireless networks designed in this way use a star or hub-and-spoke topology.