Figure 30: Telephone wires and cable TV cables represent a single point of fail-ure in their networks. Hurricanes and high winds can cause serious outages.
Some supporters of the telephone network say it offers 99.999% reliability or that it is down 5 minutes per year. That may be true of the switches in the Central Office, but is not true of the telephone network as a whole. The copper wires coming to the home or office, for example, represent a single point of failure (that is, there is no back-up if the wire or fiber optic cable breaks or is cut). Businesses using the telephone company should ask themselves two questions:
1. What does it cost us per hour to be down?
2. What back up, if any, do we have if the telephone line is cut or broken?
WiMAX service providers have no wires or cables that can be cut and can offer 99.999% of reliability by using redundant radios to cover a given market. Use of licensed spectrum ensures that only one service provider is broadcasting on a given frequency. Finally, radios with high quality chips have a mean time between failure (MTBF) of 40 or more years. If nothing else, businesses should consider WiMAX as a cost effective disaster recovery solution. Note: a backhoe operator cannot cut a WiMAX wireless connection to the home or office.