NOTE WELL: As announced January 24 2007 by OIT through a variety of media, OIT Remote Access Services this service will be discontinued on July 1 2007. A copy of the text of the announcement is available in the OIT KnowledgeBase. As a result, the information in this document is historic.
This document lists the known bugs for the Remote Access Services.
As far as we know, this does not affect services available to dial-in ARA clients, so it is not expected to have any impact. (I.e. AppleTalk services on-campus are visible in the Chooser of the dial-in client. Only the reverse direction is affected.)
Normally, this isn't actually a bug in the Remote Access service. You may often resolve the problem by upgrading the firmware in your modem. Check with your modem's vendor to learn what firmware upgrades are available for your modem; many modern modems are software-upgradable.
This is actually a bug in the client modem, rather than the Remote Access service; the client modem should detect when V.90 (or K56Flex) is infeasible, and automatically fallback to a slower protocol. The workaround avoids letting client modem attempt a higher speed connection.
Both V.90 and K56Flex protocols require extremely clean phone lines, no more than one analog-to-digital connection along the entire path, and a limited distance (e.g. about three miles) between your modem and the point at which the data is converted from analog to digital format (e.g. at the phone company's central office). Phone lines that sound perfectly clean and work well for V.34bis connections may nonetheless be inadequate to the higher demands of V.90 and K56Flex.
While V.90 and K56Flex modems should be able to detect when a phone line cannot support the faster protocols (and instead fall back to use V.34bis), in some circumstances these modems may erroneously choose to use V.90 or K56Flex. This too-aggressive behavior can lead to more connection failures, or unreliable connections.
If you encounter this difficulty, you can work around it by reconfiguring your modem so it does not attempt to negotiate V.90 or K56Flex, but instead attempts to negotiate V.34bis (a maximum speed of 33,600 bits per second). Consult your modem's documentation to learn the appropriate command to add to your modem's initialization string.