V.92 is an ITU-T
The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....

 recommendation, titled Enhancements to Recommendation V.90, that establishes a modem
A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...

 standard allowing near 56 kb/s download and 48 kb/s upload rates. With V.92 PCM
Pulse-code modulation
Pulse-code modulation is a method used to digitally represent sampled analog signals. It is the standard form for digital audio in computers and various Blu-ray, Compact Disc and DVD formats, as well as other uses such as digital telephone systems...

 is used for both the upstream and downstream connections; previously 56K modems only used PCM for downstream data.

V.92 was first presented in August 1999. It was intended to succeed the V.90 standards; however, with the spread of broadband Internet access
Broadband Internet access
Broadband Internet access, often shortened to just "broadband", is a high data rate, low-latency connection to the Internet— typically contrasted with dial-up access using a 56 kbit/s modem or satellite Internet with inherently high latency....

, uptake was minimal.

Quick Connect

This reduces negotiation times to around 10 seconds instead of over 20 seconds. Quick connect works by training the client modem on the first call; analog and digital characteristics are stored in a local profile and then retrieved for future connections.

"Modem on Hold" (MOH)

This allows the connection to be temporarily severed and then reconnected, reducing the possibility of dropped connections. This is particularly useful for lines that have call waiting.

PCM upstream

Pulse Code Modulation or PCM allows higher rate digital transmissions over the analog phone lines. PCM Upstream provides a digital connection for upstream data, reducing latency and allowing for a maximum upload speed of 48 kb/s. Previously the speed was limited to a 33.6 kb/s analog signal under the previous V.90.

V.44 compression

V.44 compression replaces the existing V.42bis compression standards. It generally allows for between 10% and 120% better compression. In most situations the improvement is around 25%.

See also

External links

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