56K Modem InformationBasics About 56K Modems
There are currently 3 different '56k' protocols in use. The X2 protocol was developed by US Robotics (now 3com) and was the first to be marketed, although it is no longer a current protocol. K56Flex was developed by Rockwell and Lucent and is now also no longer marketed by the modem manufacturers. The current 56k standard (and the protocol that all major manufacturers are upgrading to) is the v.90 protocol. While the three protocols are remarkably different, they all share the same needs in terms of line quality and negotiation properties.
Unfortunately, local telephone companies offer no guarantee of line quality, where data communications are involved. The 'official' policy, depending on who you talk to at the phone company, is that they only support something between 2.4K and 9.6K connections. Some of our customers have reported that they have contacted the local phone company and requested a "data line conditioning kit", which is something installed at the phone company's switch, and has improved their connection. Other customers have requested this and been told it doesn't exist.
If you suspect that line noise might be giving you problems with your connection, Texas.Net recommends that you do try contacting your local telephone company. If you hear any audible noise on the phone line, they should take measures to eliminate that. The phone company seems to also respond better if they get reports of problems sending faxes.
Checking Your Lines
Alternatively, if you have a Courier V.Everything modem, you can open up a communications program and type ati11. If you see a line that says Multiple CODECs, your line is not 56k-capable. We're not sure yet whether this works with other US Robotics modems. If you have a Sportster class modem and get this message, please e-mail firstname.lastname@example.org.
About 56K Modems and Connect Speeds By FCC regulation, the 56k modems cannot connect above 53K. A full 56K is theoretically possible, but we have not been able to verify that any of our customers have reached this speed. Our experience is that most connections made with 56K modems will be in the range of 40K to 50K.
If you use Windows 95/98, Dialup Networking will report either an initial connect speed or a port speed. Neither of these are particularly meaningful. Both 56K protocols continually 'renegotiate' the connection, adjusting the current speed up or down to compensate for line conditions, which do not remain constant. The new speed is not reported through Win95 Dialup Networking (or most other operating systems).
The true test of a connection is the actual data transfer rate. This can be checked by downloading a large file from a Texas.Net server, timing the download, and calculating the rate. This can be accomplished by going to our software page and downloading the Macintosh install disks with your web browser. All files are about 2.0 megabytes (simply discard the files when finished). What works even better, is to open an FTP program, connect to rsuftp.texas.net, change to the /pub directory, then download the file msie302r.exe. The WS_FTP will report a current transfer rate in Kbps (kilobits per second).
Unstable Connections and Poor Transfer Speeds
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