V.92 Modem Information

Introduction

V.92 is a new international standard for analog modems that improves on the existing V.90 standard in three ways:

• Allows you to take incoming calls while on line by putting the "modem on hold." This feature requires a call waiting service that is available from most local phone companies.
• Allows you to connect to the Internet faster. Most Internet users dial the same telephone number from the same location when going online. In this case, the modem can remember the characteristics of the call and shorten the modem start-up sequence. The start-up sequences are the sounds that the modem makes at the beginning of the connection. Savings will vary from connection to connection.
• Can improve the upstream data rate as much as 40%. Current V.90 modems are limited to upstream data rates of 33.6 Kbits/sec. The new V.92 standard extends the upstream data rate to up to a theoretical maximum of 48 Kbits/sec.

How can I take a phone call while I'm online?

The V.92 standard lets your ISP or online service put your data connection "on hold" while you pick up a voice call using your "call waiting" service. When you finish with the voice call you can resume the connection as though you had never left.

How does this "on hold" feature differ from existing modems that have a call waiting capability?

Call waiting support is significantly improved under the new V.92 standard. While some modems support call waiting service from local phone companies now, the Internet connection will be terminated if you take the call and talk for more than about 7 seconds. The V.92 standard allows an Internet Service Provider to establish how long they will allow users to take calls while still maintaining their Internet connection.

Why should I buy V.92/V.44 when DSL and/or cable are available?

Certainly the promise of faster connectivity from DSL or Cable modems has been very compelling and the speed improvements offered by these type devices are much greater than the improvements offered from V.92/V.44. According to the International Telecommunications Union, "the analogue modem will remain the pre-dominant access technology for the masses for many years to come." Today, analog modems work everywhere and both DSL and cable modems work in a more limited user space. Also, the price of these modems and the hidden costs of installation, home wiring considerations and truck rolls can make the transition to these new technologies less than ideal.

How can the data transfer rate increase if V.92 analog modems are limited to 56 Kbits/s downstream and 48 KBits/s upstream?

These rates describe the rate at which bits can be transported over the wire and is often referred to as the line rate. By examining the bit patterns of the data, it is possible to compress or pack the data prior to transmitting and unpack the data when it is received. In this way the actual amount of data transmitted at a given line rate will exceed the rate of the line.

So how much improvement can I expect to see with V.44?

The International Telecommunications Union (ITU), the international body that develops and approves these standards, has stated that V.44 gives an improvement in compression of more than 25% beyond the existing V.42bis standard. Actual improvement will vary depending on the type of data that is being compressed.