ULTIMATE Internet Access, Inc. - Claremont, California

56K modems work in a much different way from older modems, and as such they are sensitive to many problems that do not affect slower modems. Be sure to read all of the materials on this page to learn more about how 56K modems work, and why they sometimes don't. If you have additional questions not answered here, please e-mail us at technical@uia.net and we'll be happy to assist you.

56K v.90 Modem Information

ULTIMATE Internet Access, Inc. now offers 56K modem access for all varieties of 56K modems, including x2 (US Robotics/3Com), K56flex (Rockwell/Lucent), and v.90 (ITU standard).

If you have a v.90 compatible modem...
Most new 56K modems being sold today include the v.90 standard code. However, this standard has not yet been ratified, and as a result various different versions of this "standard" code exist. This means that even if you have v.90 in your modem, it still may not connect reliably to all v.90 access numbers. If you encounter problems with a particular number, we recommend trying the other number for your area and subsequently using the number which provides the fastest and most reliable connections for your particular modem.

If you have an x2 compatible modem...
Most x2 compatible modems are "flash upgradable" to the v.90 standard. This means that with free software you can download from the Internet, the internal code in your modem can be upgraded to support the v.90 standard without the need for purchasing any additional hardware or software. To find out if your modem is upgradable or to download the upgrade, please visit the 56K Central page at the 3Com/US Robotics website.

Please note that some early x2 modems (manufactured before mid-1997) are not v.90 upgradable and may not be able to connect above 33.6K with our equipment. Additional information about these modems is available at 3Com's 56K Central.

Owners of US Robotics or x2-compatible modems, even if they've been upgraded to the v.90 standard, are encouraged to use our US Robotics-compatible access numbers, which end in 3766.

If you have a K56flex compatible modem...
As with x2 modems, we recommend that owners of K56flex modems upgrade their modems to the v.90 standard. Most K56flex modems are upgradable, but due to the wide variety of name-brand manufacturers and poor-quality "no-name" K56flex modems made, finding the right upgrade is a bit more difficult than with x2 modems. We recommend consulting the modem owner's manual or visiting the website of the modem manufacturer to find upgrades.

UIA's v.90 access numbers which end in 4199 are backwards-compatible with K56flex, but again, the variations in quality and components used by the numerous K56flex modem manufacturers may prevent certain non-upgraded K56flex modems from getting fast or stable connections.

General caveats about 56K modems...
In order to obtain their fast speeds, 56K modems use compression and encoding methods that are much different from those of standard modems of 33.6K and lower speeds. Also, unlike 33.6 and slower modems, which use an analog signal, 56K modems use a digital signal for sending data through from the Internet service provider to the user. As such, these modems are sensitive to many conditions that do not affect slower modems. These conditions include the condition of phone lines, the number of switches between the user and the ISP, and even the distance of the user from the phone company's central office for their area.

In some cases, the phone company also uses a system called SDC (subscribed digital carrier) instead of standard analog phone lines, when regular phone line pairs are in short supply in a particular area. SDC is transparent to users during voice calls or when using analog modems, but because of its digital nature and the limited bandwidth it provides, 56K modems often cannot connect above 26.4K when used on an SDC phone line.

If you experience any problems similar to those described above, you may wish to contact us for tips on arranging to have the phone company switch or repair your phone line.