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Xwho? Kwhat? v.huh?
Recently two major new modem standards were announced. Kflex from Rockwell and Lucent, and X2 from US Robotics. Both provide faster connections, up to 56 Kilobits. Since it seemed silly to have two standards, everyone has settled for one compatible standard called v.90 or v.pcm. It took the best of both protocols. Bottom line is it's the fastest connection you can get over a regular phone line, roughly twice the speed of the older v.34 (33.6 Kb/s) standard.
Will my modem work with this?
v.34, X2, v.90 and all the slower protocols will still be supported.
What about my Kflex modem?
Check your modem manufacturer's webpage for an upgrade. Most modems that support Kflex are flash upgradeable. If you bought from a reputable manufacturer, it should be a free upgrade.
Can you help me upgrade my X2/Kflex modem?
No. We can help you find their tech support page though.
I have X2, should I upgrade to v.90?
Good question. If you're the type of person that likes to be on the cutting edge, or you currently have phone line problems, give it a try , but you should have the software to downgrade in case it gives you any problems. If you're conservative, wait for the next release of modem code, especially if you are happy with your current connect speeds.
I have Kflex, should I upgrade?
If you have a Kflex modem and you dial into INCH, your highest connect speed will be 33.6 Kb/s. If you upgrade to v.90, you should see a significant speed increase. Since there are a wider variety of manufacturers making Kflex modems, there is a greater chance that you may have problems getting tech support, finding the upgrade, etc. If you upgrade, make sure you have a backup of the old software in case there are any problems.
My connect speed is slower now!
The v.90 protocol is more conservative in the initial negotiation (the one your software reports when you dial in). It generally will get faster in the first minute or so of your connection. The reason for this is it tries to get a feel for the line quality over a period of time so it can adjust to the optimum speed. The only true test of connection speed is not what your software shows on connect, but the speed of your downloads. Try downloading something via ftp from an inch server ( and take a note of the speed. Anything over 5 KiloBytes/Sec is very good. If you've upgraded and you see very poor speeds, downgrade to your old modem software and call the tech support department for your modem.
What's so great about this new v.90 thing?
It's a small improvement over X2 and a little more of an improvement over Kflex. It can handle poor line conditions a bit better, and it maintains more stability once the connection is made. Overall throughput is slightly improved. The most important thing is that it is a standard that all modem manufacturers will follow, so you can purchase any v.90 modem and connect to INCH at a higher speed.
Is this the time to buy a new modem?
If you are still using a modem with a maximum speed of 33.6 or lower, and it is not upgradeable, yes.