Enable simultaneously wifi and 3G interface on Android

Question

Is it possible to have both 3G and Wifi connections up and running? I want to transmit at the same time through both interfaces.

However, I've noticed that when Wifi is up, 3G is going down. Actually, it seems that the routing table is updated on on/off of the interfaces.

1. Route table UMTS on / Wifi on

   a.b.c.1 dev rmnet0 a.b.c.0/24 dev rmnet0 src a.b.c.2 default via a.b.c.1 dev rmnet0

2. Route table Wifi on / UMTS on

   192.168.1.0/24 dev eth0 src 192.168.1.147 default via 192.168.1.1 dev eth0

3. With wifi on I have run:

   ip link set rmnet0 up

   ip route

   192.168.1.0/24 dev eth0 src 192.168.1.147 a.b.c.0/24 dev rmnet0 src a.b.c.2 default via 192.168.1.1 dev eth0

When I saw that I thought that I have managed to put both devices up and running. However, this is not the case. When I ping a public internet address (a.b.c.3), in case 1) and 2) everything goes well. In case 3) I get no answer.

Where on earth does Android set that only one device can be available at a time? How can I make both interfaces to be up and available, like on an ordinary Linux box?

P.S.: I have tried the solution in [1] to enable the data connection when wifi is on, and no way.

[1] How to enable data connection on Android 2.3

[2] How to block calls in android --> using ITelephony to get the telephonyService.enableDataConnectivity(); but I get an exception.

Answer 1

This is not going to be possible... unless you are will to go to great lengths to make it work. You are essentially asking for you device to become a router.

To do this you will need to find a program (sorry can't remember any names at the moment) that will accomplish this on a normal linux distro. Then recompile it to fit the Android OS and install is into the native system.

This explanation may make a little more sense to you. If you go to your ADB shell and run netcfg (or ifconfig to verbose this) you will see the devices networking options. You can run an ifconfig command to set the device or change its state - but you cannot have multiple devices route data to and from the phone at the same time I wouldn't think.

This would be my best guess...