Anyway, the instructions (or firmware/software) that come with most routers is limiting and does not give you all the options a professional router might have as far as bandwidth monitoring, bandwidth control, and other stronger security options. Not all routers are upgradeable. In fact, recently home router makers are now building their routers as not to be upgraded. You almost have to get a premium router to have a chance a getting the extra features. One of the most popular routers is the wrt54-g(l) from Cisco Linksys. When I see one at a resale store, I think about getting it. Most firmware sites will have a listing of what can be upgraded with their firmware.
There are several ways to upgrade firmware. All of them entail uploading or sending a file to the router to replace the existing software in it. The most common way is to upload a file via the web interface on the router. That is what we will do. Some routers may require a tftp server to send the remotely to the router and is a bit more complicated. The most complicated install is a redboot which requires special communication with the router. These can be the most challenging. I have done one and prayed all the way through it.
NOTICE: Have a pencil and paper to write down any settings or options that might be needed later. This project could render your router useless. If you are unsure, please get a professional to help before starting on it. I will not be responsible for any issues, You do this at your own risk.
Step 1: Getting the Firmware.
What alternative firmware is available. Some of the most popular ones are:
* HyperWRT Thibor
* OpenWRT (Comcast has their footprint on this one.
For our purposes, we will be using the DD-WRT firmware. The router we plan to use is a Cisco Linksys WRT54G version 2. so we need to go to www.dd-wrt.com to get the firmware. At www.dd-wrt.com press the router database button. You will then be presented with a form to enter the name and model of you router. (entering in the just router model can save time). You will then be presented with a list of routers that meet your request. Now look in the next to last right hand column to see if it says "yes" which means you router can possibly be upgraded. if it says "no" then you are done and your router can not be upgraded. If your router can be upgraded you can press on that choice to get options for firmware to download. Sometimes certain versions are recommended for the first upload or (flashing) of the router. READ CAREFULLY!!
Go ahead and download the recommended firmware.
HINT: make sure you have a way to get on the internet in case in the next step in case things go bad. Never hurts to have a cheap router as a spare.
Step 2: Upgrading the Firmware.
You will need to connect to your router. So open a web browser and go to 192.168.1.1 (default address). At this point. you will be asked for the log in name and an administrative password. If you have not already changed these, then consult the manual for that information. Lacking a manual, then go to the make of the routers support site. One thing I do recommend is to disconnect the antenna from the router before doing a upgrade of the firmware. It lessens the chance of being hacked while doing the upgrade. I also recommend immediately turning off the radio and changing the admin password. (make sure you are connected to the router with an ethernet cable not wirelessly.)
Now go to the administration section and click on the firmware upgrade tab. You will be presented with a file selector to choose the file you just downloaded from www.dd-wrt.com. So select the file where you downloaded it to. Once you are sure you have selected the right firmware file name recheck it. if it is ok then click on upgrade. NOTICE: once you have started the upload do not disturb the router or your computer till it is done. You could brick the router if you do.
You should get a bar graph at the bottom or the screen as to progress. The router will eventually reboot and you will be presented with a new log in screen. BE PATIENT!!! it does take a few minutes.
Step 3: New Firmware.
If all went well, you should have a completely new screen with lots of more options to your liking. www.dd-wrt.com support pages can get you the details you need for your configuration. Good luck!
Step 4: Command Line
. : [ [[ alias bg break cd chdir command continue echo eval exec
exit export false fg getopts hash help jobs kill let local printf
pwd read readonly return set shift source test times trap true
type ulimit umask unalias unset wait
Step 5: ISP Integrity.
Step 6: What's on Your Network.
Step 7: CoovaAP
Step 8: Openwrt.
PC openwrt install: https://www.instructables.com/id/Upgrade-a-home-router/