Connecting Android Phone Through Adhoc Wifi Network
An Android phone works perfectly when you have a wireless connection, either through wifi wireless AP or mobile network GPRS. However, when it comes to places where only wired connectivity is available, for instance an Ethernet connection or a dial-up connection, or when you're roaming and using mobile network's data roaming might cost you a fortune, some workaround must be done.
My HTC Magic works fine back at home. I got both unlimited wifi and GPRS connectivities. But when I roam elsewhere, which I do a lot, the data roaming cost would be too high and most hotels I stay have no wifi but only wired Ethernet in-room.
One thing which I know will work is to carry with you a wireless AP, plug the LAN cable in, and you're all set. But I don't want to add any more weight to my bags. So I think about turning the laptop into an access point instead.
So I did some searches and found a very useful information at modmygphone.com's forum. The thread mentioned configuring your G1 Android phone to connect to a laptop's ad-hoc wireless network. That's exactly what I need!
I didn't modify the files directly on the phone, but instead I used adb pull the 2 files onto my laptop, then edited the files, then adb push them back. So the steps were:
> adb pull /system/etc/wifi/tiwlan.ini tiwlan.iniYou will see your ad-hoc wifi network name in networks list (Settings -> Wireless controls -> Wi-Fi settings). Phone modification part is complete.
> adb pull /data/misc/wifi/wpa_supplicant.conf wpa_supplicant.conf
[.edit tiwlan.ini and wpa_supplicant.conf according to the guide]
> adb shell
# mount -o rw,remount -t yaffs2 /dev/block/mtdblock3 /system
# exit
> adb push tiwlan.ini /system/etc/wifi/tiwlan.ini
> adb push wpa_supplicant.conf /data/misc/wifi/wpa_supplicant.conf
> adb shell
# mount -o ro,remount -t yaffs2 /dev/block/mtdblock3 /system
# exit
>
Now back to the laptop. An ad-hoc wireless connection has to be created and Internet Connection Sharing enabled. There are many guides available on the Internet. (for example here.) When it's created, in "Choose a wireless network" window, select your ad-hoc network and click "Connect." Your phone and laptop should try to connect to each other and you're all done!
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In case you're unlucky and your hotel network assigns IP address in 192.168.0.0 net, ICS will not work. Try create a network bridge between the wireless connection and LAN connection instead.
Have fun with your Android! ;-)