Too often, I hear people using the terms bandwidth and broadband interchangeably. They are not the referencing the same thing.
Bandwidth has its origins in the analog world, and is related to hertz, or frequency. In the world of RF, there is also signal bandwidth or analog bandwidth. Bandwidth is also used to describe light, such as spectral bandwidth. However, in the digital world, bandwidth is clearly used to reference speed, which can then be used to calculate capacity. For example, Unified Communications requires more bandwidth than simple VoIP. VoIP without compression requires 64kbps. A UC voice channel typically requires 88-96kbps.
Bandwidth for the IP Community is nearly always referred to in terms of bits per second, the range of which is infinite in either direction – more bits per second or fewer bits per second. So, if bandwidth is about speed, what is broadband?
Broadband, as described by the FCC, requires a minimum bandwidth of 256kbps. The term broadband is applied to a transmission media that can support multiple signals simultaneously. As with bandwidth, broadband has historical references to radio and TV. It also is related to terms such as narrow band and wide band. However, for this discussion, we will refer to broadband as it applies to the Internet. In that context, we view broadband as delivered using copper, fiber, cable, wireless (Wi-Fi, 3G, 4G, LTE), satellite, etc. The types of broadband include DSL, ADSL, SDSL, T1, DS3, Cable modem, etc.
Perhaps, this primer is only useful to a few of you. But as we sell VoIP, Hosted UC and SIP Trunking, it is necessary to understand the difference between a request for broadband, and the bandwidth required to service the customer.