This isn't an open source router. There is no functional Tomato software. This beta software is at present unusable.
How To Install Tomato Firmware on NETGEAR WNR3500L
Categories: Setup / Configuration Tomato
Once you get your hands on the NETGEAR WNR3500L, you'll probably be pretty tempted to start hacking away; unleashing the power of this brand new open source monster. Along with other builds of ready made firmware, a BETA version of the ultra-stable Tomato firmware is available.
What is Tomato Anyway?
Besides actually being a fruit, rather than a vegetable, Tomato is a router firmware with a reputation for being super stable and useful. It features an easy to navigate GUI, bandwidth monitoring features, as well as a whole host of other useful bits. Read more about the Tomato firmware at the official site.
How To Install Tomato on your WNR3500L
Alright, on to the good stuff! The first thing you'll need to do is download the WNR3500L specific build of Tomato. You can find it (and a link to the source code) here.
Warning: Before you proceed, the BETA version of Tomato being used for this tutorial may be unstable and may also pose multiple security risks. It would be best to limit your usage of this early build to testing purposes only. Please watch the community for new firmware releases, and read the release notes for full details.

Go ahead and log into your WNR3500L over your network by typing in 192.168.1.1 into your browser (or whatever IP address you chose.) You'll need to type in your administrator username and password, and you'll be brought into the NETGEAR standard firmware. Look at the links on the left, and click "Router Upgrade."

You'll be brought to the screen that you see above, where you are able to either update the standard firmware over the Internet, or manually choose a firmware to flash to the router. You'll want to click the "Browse" button and select the DD-WRT firmware. Once this is done, click "Upload."

You may be asked if you want to continue, something similar to the screen shown above. For Tomato, I did not see this screen, but if you do - select "Yes."

Once you proceed, the firmware update will begin. DO NOT power down your router or otherwise mess around with the flash... if you perform a bad flash, you may have to debrick the WNR3500L (and that is a much more detailed process than this.) Also, it takes a bit longer than a minute and a half like it states; patience is a virtue. Wait for it to finish completely.
A Quick Tour of Tomato for WNR3500L

Once Tomato is finished loading, you may want to reboot your router just to be sure. Then, access the Tomato GUI through 192.168.1.1. You'll be met with a password screen; type in the defaults above. It's highly recommended that, even during testing, that you change these default security settings.

Once you've gotten into the Tomato GUI, you'll see the status screen as shown above. The current settings appear in the center panel, and you can access different sections of the firmware settings using the menu items on the left.

First, I would recommend heading to the Basic => Network tab to set your SSID and security settings. Remember, WPA is currently not functional in this BETA build, so WEP is the best you'll get at this point. Even during testing, it's recommend that you change these settings.

You should also change the password of the GUI in the Administration => Admin Access panel as shown above.

One of the unique features of Tomato is the built-in, realtime bandwidth monitor, which can also display results over the last 24 hours, weekly, or monthly.

Tomato also supports custom port forwarding settings.
Moving Forward
As you probably could have guessed, Tomato is loaded with customization options and some unique features to really unlock the power of your WNR3500L.
As stated before, the current build is experimental and due to missing features and potential security risks, probably not recommended for daily use at this point. However, the future of Tomato for the WNR3500L is bright andI can't wait until a stable, final release is available.
I hope you enjoyed your sneak peek of this upcoming firmware. If you have any issues or questions, don't hesitate to post them on the forums, and make sure to watch the community as well as our Twitter account for firmware updates and news.
Quick Links
I tested this with the current build of:
tomato-1.27-NDUSB-9044MIPSR2-beta05u-Ext
If the file extension is .trx (default) or .bin, I get this error message:
Invalid filename was provided, please enter again:(*.chk)
If I change the file extension to .chk, I get this error message:
Firmware upgrade failed. Please check your file.
... just reporting my experience. Feel free to update me on any changes. I prefer Tomato over DD-WRT, since I've had stability issues with the later. Also, Tomato seems simpler and has a pretty awesome community.
View unverified member's comment - posted by st4lm3n


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