Hi everyone!!!
Now I'm using Fedora core 5. I want to connect to internet with USB Modem Planet ADU-2100 (It works well in WinXP).This modem only have one USB port and no Ethernet port. Please help me...

What you want to know is the Vendor ID. Plug in the device then use "lsusb" or "usbmodules" or equivalent command to see if any modules got loaded and look at your syslog for messages about USB. If it returns any info like Vendor ID strings use that to search the Linux-USB device overview website or see for instance http://eciadsl.flashtux.org/modems.php for chipset references. If those two don't show info chances are the device is not supported (yet). Try to post as much (and exact, please) information you can. Maybe we can help you find a driver.

Did YOU purchase the Modem yourself? If YOU have the CD-ROM driver disc, it may have the Linux driver on it. Worth the time to scan it. If not...it would be best for YOU to purchase an External Serial Modem. It connects to the serial port on YOUR Motherboard. Most Linux Distro's have the drivers for the chipsets already included. See www.pricegrabber.com for low-cost, high-quality Modems. Usually between $25.00 to $35.00 with the shipping. Or higher if YOU want the higher priced hardware. The controller chip on the circuit board does the work. Not the processor. USB relies on the software. If YOU find the software, go for it. First try the hardware part labels, then the documentation included, then the website.