The Operation of V.90 Modem

The V.90 is a modem standard developed by ITU. It’s compatible with most of the ISPs now since the ITU agreement has been made in 1998.

The downloading speed of V.90 modem is 56Kbps. When V.90 modem downloads data it use digital technology and it’s only for downloading. Since V.90 modem use digital technology for downloading data, therefore it doesn’t have to do the analog to digital conversion, so the speed of the network won’t be slow down by the Quantization Noise. The process of the Analog to digital conversion have to match the analog waveform to corresponding digital levels, but there can not be a exact march, so it can only take a range from the waveform to a approximate digital level and this process is called Quantization Noise. V.90 modem still uses analog when uploading data and having a transfer rate of 34 Kbps. By theory the telephone network only can afford 35Kbps maximum data transfer rate when using analog.

The V.90 is the most popular modem standard today, because it’s capability. A phone line will easily let users connect to their ISP or other networks.