Networking at home

In my previous post , I have explained how to setup a 3G/4G modem with USB connection emulating a serial device, in this post I will explain, how to set it up with a modem emulating network connection on the USB interface, like the ZTE MF-821D. The same method applies if you want to use an Android phone as a modem.

In my previous post , I have explained how to upload an OpenWRT image to the MPR-L8 or A5-V11, now we will go trough how to set it up for working as a mini 3G/4G router.

These small routers have a built in telnet service, which can be reached by telneting to the router with your favorite telnet client (e.g. Putty). The user name is admin and if you have not changed the password it is also admin.

If you have one of these modems you may have encountered the problem, that on first try your USB 3G modem is working very well, and later it is not working at all. In this post I will explain a very easy trick, on how to fix this issue.

The MPR-L8 is very nice and cheap mini router, having also an USB port and a built in battery. From the factory it has a very capable firmware, providing support for 3G dongles for mobile internet sharing, media and file sharing from USB devices and compared to its very small size has all the filtering and port forwarding functions, that normal sized routers provide. Unfortunately the factory firmware is not very stable and we may want to add additional functionality like support for 4G modems or use it as an OpenVPN client to connect easily to home network from any location. All this is possible by flashing an OpenWRT firmware and setting it up according to our needs.

This post is about experiences with hacking into the MPR-L8 and my attempts to install modified firmware to the router. At the end of the post there will be links to the simply uploadable OpenWrt firmware along with the original firmware to be able to restore the router.