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This is our growing collection of troubleshooting tips for those who are having difficulty establishing a connection to the DU modem pool with their 56K modems.
![[*]](Bullet2.gif){kind=small} DU's modem pool information
The University of Denver has a total of 192 modems available for use by the DU community. These modems are 3COM Total Control Modems using the X2 protocol and V.90.The distribution is:
Complete modulations that are supported:
General information about the modem pool can be found at our Modems at the University of Denver page. Information about establising your remote dial-up connection can be found at our Online Documentation page.
Explanation of 56K technology
Even though 56K modems have been available for several years, the technology and standardization are still in development. Before February 1998, there were two divergent 56K modulations: X2, based on the U.S. Robotics/3Com chipset and KFlex, based on the Rockwell (Conexant) and Lucent chipsets. In February 1998, the ITU 56K modem standard, called V.90, emerged. Before the V.90 standard, if you had an X2 modem, you were required to use an X2 Internet Service Provider (ISP). Likewise, if you had a KFlex modem, you were required to use a KFlex ISP. Since V.90 has emerged, ISP's using either of the proprietary 56K technologies, X2 or KFlex, have needed to upgrade their equipment to support V.90. Modem manufacturers, as well, have been updating their modems to make them V.90 compatible. The V.90 standard is an attempt to make the proprietary technologies (X2 and KFlex) entirely compatible. Because the V.90 standardization is still relatively new, many ISPs and modem manufacturers have been required to make several updates to their equipment as new information develops. It is very likely that a newly purchased modem or computer with a modem will require one or more V.90 driver updates before full functionality is obtained. Drivers are software (written to Windows 95/98 system files) and firmware (written to a special electronic chip on the modem itself) which contain programming code instructing your modem on how to perform. Without drivers, your computer's operating system would not know what purpose your modem serves. Drivers are installed during the installation of your modem, for example, either automatically by using a driver database included with Windows 95/98, or manually by using additional diskettes or a CD-ROM provided by the manufacturer.
What you need to achieve 56K
True 56K connectivity is a fallacy. FCC regulations limit the maximum speed for a modem over telephone lines to 53 kbps. Connection rates in the mid-40K range are most common. Connection speeds above 50K are rare. There is no way to know if you can take advantage of 56K connections until you try a 56K modem. And, even if you can achieve 56K connectivity, your connection speeds may vary significantly. If you purchase a 56K modem, you may get great connection speeds right out of the box or you may discover that your telephone line does not support 56K, requiring you to connect at V.34 (28.8 or 33.6 kbps speeds). More likely, you will find that after one or more driver upgrades and calls into tech support, you will achieve connection speeds somewhere in the middle. There are 3 things you need to take advantage of 56K technology:
56K connectivity problems
We have witnessed several connection problems for owners of 56K modems who are trying to establish a remote dial-up connection to the University of Denver modem pool. Several of these symptoms are: In all cases, the modem never actually establishes a functional connection with the DU modem pool. The modem may even connect to other ISPs like AOL, Earthlink, AT&T Worldnet, etc. These connectivity problems can be attributed to many things:
If you have more than one analog-to-digital you will not achieve 56K and your modem should fall back on V.34 speeds (28.8 or 33.6 kbps), still allowing you to connect. Some modems have been known to fall back on Kflex instead of V.34. If your modem falls back to KFlex, it will not establish a connection with the X2 technology of the DU modem pool. A good V.90 driver, or using special AT commands for your modem, can prevent this. AT commands are "attention" commands used to control the behavior of a modem.
Determining your brand of modem
Please see our instructions, Determining 56K
Modem Properties And Driver Information For Windows 95/98 for help
determining your modem properties. These properties include the name of
your modem, its connection capabilities and driver revision numbers or
dates. This information is needed in order to determine if your modem
manufacturer has released any driver revisions which may improve its
connection speed or reliability.
Help Desk success stories
The UTS Computer Help Desk helps members of the DU community troubleshoot their modem connections. After the Summer of 1998, when University Technology Services upgraded the modem pool to 56K, we have seen an increase of trouble calls related to 56K modems. Please visit our 56K Data Page for details on discoveries we have made, downloads for common 56K modem drivers (ones that the Help Desk has been distributing), other driver information, Help Desk modem troubleshooting secrets, and other miscellaneous data.
Our recommended list of modems
We have seen the good and the bad. We recommend the modems below because
of their ease of installation, available support from the manufacturer,
good performance with the DU modem pool, and ability to manipulate the
modem's behavior with drivers and AT commands:
Links for driver updates and 56K sites
Drivers and information for the LT Win Modem or Rockwell HCF 56K Modem can be found on our 56K Data Page. Below are some links to the online support sites for many of the modem manufacturers and helpful 56K websites:
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