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By Hervey Allen (hervey@oregon.uoregon.edu)
Last February, we upgraded the UO modem pools with new Cisco equipment and consolidated them at 346-6520 (see "UO Modem Pools Consolidated" in this issue).
While this upgrade has benefited most users, a few have had problems connecting. Some people reported problems getting their existing setups to work as well as before. Either they couldn't connect at all, or their connection was inexplicably slow.
In almost every case, the problems we've seen were related to WinModems or modems that did not properly support standard protocols. If you're troubleshooting a modem problem, the first place to look is in one of these two areas. Remember:
1. We support standard protocols only (this means V.90--not X2, KFlex, V.FC/V.Fast, etc.)
and
2. WinModems/host-based modems continue to have all sorts of problems (see "WinModems: A No-Win Situation?" in the Winter 2000 issue of Computing News)
With these facts in mind, here are some typical problems we have seen and their possible solutions:
A SupraFAXmodem previously connected without problems; it now connects much slower or not at all.
Possible Solution:
The modem may be using V.FC/V.Fast to connect. This protocol is no longer supported.
Try going to the Supra/Diamond Legacy support web pages at http://www.diamondlegacy.com/ to see if there is an update for your modem. If not, you'll need to use an AT command to tell the modem to connect using V.42bis (try ATF17), or at 14,400 bps. As far as we know, there is no upgrade from V.FC to V.34 (28,800 bps) for these modems.
Note: Use of AT commands for modems differs for each operating system and type of dialin software. The exact AT command required also differs; you should be able to find it in your modem manual. If you need help with AT commands, you can contact Microcomputer Services at 346-1412. Because of the complexity of the AT command solution, however, you may find that a new modem will serve you better.
You have a K56Flex and/or X2 modem, but not a V.90 modem. The modem either no longer connects, or it connects at a slower speed.
Possible Solutions:
Go to the modem manufacturer's web site to see if there is a software update for your modem.
Each manufacturer or modem model has a different process for applying these software updates. On some WinModems, you'll need to update the drivers installed under Windows. On non-WinModems, you often need to update the modem's internal code ("flash the firmware") on the modem to effect a change.
Note:
- 3Com now owns US Robotics. Try http://www.usr.com to find software for legacy US Robotics modems.
- Mac users of US Robotics modems may need to download a special tool from the USR/3Com site to determine exactly which modem they have and what update they need.
- Supra modems with K56Flex support that do not have a firmware update may still offer a chip swap program. Call the Diamond/Supra tech support center at (254) 299-2756 and have the correct product ID handy. The last time we called, the support staff indicated they would still send a new chip with V.90 support--but only for Supra modems that don't have a firmware update option.
See Diamond/Supra's web page at http://www.diamondlegacy.com/ to determine what product you're using.
You have a modem that supports V.90 and has secondary support for K56Flex and/or X2. It no longer connects, or connects at a slower speed.
Possible Solution: We've seen multiple modems with V.90 support that don't connect or connect at slower speeds. In general, modems that are relatively new (i.e., modems purchased within the last six to nine months) won't have this problem.
However, many older modems that were flashed to support V.90 do have this problem. This is because some of them first try to connect using X2 and/or K56Flex before they'll try V.90. The problem lies in the way the modem falls back to V.90. Often this is done incorrectly and the whole connection fails.
In most cases, the solution is to go to the modem manufacturer's web site to see if there is a firmware update for the modem. After you apply the update, chances are the modem will connect correctly. The update will often make the modem first try V.90 and/or it will install an improved fallback mechanism.
Alternatively, you can often use AT commands to force the modem to connect using V.90 instead of X2 or K56Flex.
You have a WinModem/Host-Based modem that was connecting, but which now fails to connect.
Possible Solutions:
There are many reasons why this may be happening. Perhaps the WinModem is trying to connect using K56Flex and/or X2. In such cases, updating the modem driver is often the fix.
The problem with WinModems is that applying the update can be anywhere from trivial to incredibly complex depending on the manufacturer. Even worse, many WinModems are essentially unsupported, and no updates are available.
Some WinModems do such a poor job of negotiating connections that turning off this feature can get them connected. (But note that if this works, you have no error correction--which means you will probably drop your connection pretty quickly.) If doing this, or connecting at much slower speeds gets you in, then it may be time for a new modem. You will definitely want to see if there is a driver update for the modem.
You were dialing in without problems, but now you get repeated prompts to enter the password.
Solution: What's happening here is that our modem pool now correctly supports the ability for Windows to prompt you several times if you have entered your password incorrectly in the original dialup box.
If you enter a password incorrectly three times, the connection is dropped. We consider this a plus because it gives you several chances to type your password correctly before losing your connection.
In every case, people who called to complain that they were inexplicably getting the multiple password prompt had either changed their modem password without realizing it, or they had inadvertantly typed it incorrectly. (A typical error is accidently leaving NUM LOCK on when typing a password.)
Most of the problems I've described affect only older modems that don't support V.90 correctly, or inexpensive modems that make poor connections/don't correctly support standard communication protocols.
For the majority of modem users, there are definite benefits to our modem pool upgrade and consolidation. First of all, the modem pool is now larger. This means you have a better chance of being able to connect during peak times. In addition, the lines cost less, and our modems are much more reliable and are easier to configure and maintain.
If you need help checking for WinModem updates or downloading files, contact the Microcomputer Services staff (microhelp@oregon, 346-4412), or stop by their office in Computing Center Room 202.