56K Modem Information

Basics About 56K Modems
There were in the past 2 different '56k' protocols in use. The X2 protocol was developed by US Robotics (now 3com) and was the first to be marketed. K56Flex was developed by Rockwell and Lucent and is now also widely marketed by many modem manufacturers. Now there is an official V.90 protocol. While there are significant differences between the three protocols, they all depend on the same set of conditions in order to work properly.

Requirements
All protocols assume the phone line is part of a modern Public Switched Telephone Network (PSTN), which most areas now have. The protocols work by taking advantage of the digital connections that ISPs use to connect to the PSTN. Typically, the only analog connection between your modem and your ISP is the one between your home and the phone's switching office. If there is more than one analog-to-digital conversion in the loop from your house to the ISP (if the phone company has some extra analog switch), then neither protocol will achieve the increased performance.

Phone Lines
V.90 depends on high quality phone lines between your modem and the local phone company's digital switch. Any noise on this portion of the lines will result in deteriorated performance. This 'noise' is not necessarily audible sound. All phone lines carry some degree of 'noise'.

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.

If you suspect that line noise might be giving you problems with your connection, Coinet 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. About 56K Modems and Connect Speeds If you use Windows 95, Dialup Networking will report either an initial connect speed or a port speed. Neither of these are particularly meaningful. All 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).

Unstable Connections and Poor Transfer Speeds
Modem manufacturers were very eager to get their new high speed modems on the market. Both the X2 and the K56Flex modems and some V.90 modems were initially released in a very problematic state. Both offered unstable connections and transfer rates. Almost all modem manufacturers now have firmware upgrades available for these early versions. See below for details on checking 56K modem versions. See our FAQ with regard to problems with WinModems as well.

Modem Updates and Links
If you would like to experience better performance from your internet connection, the manufacturer of your modem may have information or updates that might help. Coinet uses the new V.90 standard on our 56K dialin ports. Upgrading to V.90 will give you the best possible performance from your modem.

The following list is far from complete. Most, but not all, modem manufacturers have V.90 upgrades available. The list below should assist you in finding information and V.90 updates for several modem brands and models.