The Linksys WRT54G (and variants WRT54GS, WRT54GL, and WRTSL54GS) is a Wi-Fi capable residential gateway from Linksys. The device is capable of sharing Internet connections among several computers via IEEE 802.3 Ethernet and IEEE 802.11b/g wireless data links.
Linksys released the WRT54GL in 2005 to support third-party firmware based on Linux kernel|Linux, after the original WRT54G line was switched from Linux to VxWorks, starting with version 5. The WRT54GL is technically a reissue of the version 4 WRT54G. Cisco was FSF vs. Cisco|sued by the FSF for copyright infringement, but the case was settled.
|Version||CPU||RAM||Flash memory||S/N Prefix||Notes|
|1.0||Broadcom BCM5352 @ 200 MHz||16 MB||4 MB||CL7A||New model line, released after the version 5 WRT54G, which returns to a Linux-based OS as opposed to the VxWorks firmware. SpeedBooster is not enabled in stock firmware, however third-party firmware will enable the feature. The hardware is essentially the same as the WRT54G version 4.0. One alteration is that the internal numbering scheme of the 4-port switch changed in this model, from 1 2 3 4, to 3 2 1 0.|
|1.1||Broadcom BCM5352 @ 200 MHz||16 MB||4 MB||CL7B CL7C CF7C||Tomato, OpenWrt, and DD-WRT.|
Third-party firmware projects
After Linksys was required to release the WRT54G's firmware source code under terms of the GNU General Public License, there have been many third party projects enhancing that code as well as some entirely new projects using the hardware in these devices. Three of the most widely used are DD-WRT, Tomato Firmware|Tomato and OpenWRT.
Hardware versions affect firmware compatibility
As of January 2006, most third-party firmware is no longer compatible with version 5 of both the WRT54G and the WRT54GS. The amount of flash memory in the version 5 devices has been reduced to 2 MB, too small for current Linux-based third-party firmware. (See table above for information on identifying the version based on the serial number printed on the bottom of the unit, and on the outside of the shrink-wrapped retail box.)
Some users have succeeded in flashing and running a stripped down but fully functional version of DD-WRT called 'micro' on a version 5 WRT54G.
To support third-party firmware, Linksys has re-released the WRT54G v4, under the new model name WRT54GL (the 'L' in this name allegedly stands for 'Linux'). It is also possible to replace the 2 MB flash chip in the WRT54G with a 4 MB flash chip. The Macronix International 29LV320BTC-90 is a suitable part although others may work as well. The user must first install a JTAG header and use a JTAG cable to backup the firmware, then replace the chip and restore the firmware with the JTAG cable. After testing for proper functionality of the modified unit, third-party firmware can be flashed using the JTAG cable and a suitable image file.
According to OpenWrt, the Linksys WRT54G series use several different processors, all of them 32-bit MIPS architecture processors, most manufactured by Broadcom.
- IP address: 192.168.1.1 (WRT54G-TM and WRT54G-RG: 192.168.0.1)
- Web interface username: "root" for most routers, no user name on some
- Password: "admin"