Always-on networking via GPRS (original message)

Nuutti Kotivuori naked at
Wed May 2 16:02:44 CEST 2007

think something filtered it as a duplicate. Here is the original 
message in it's entirety. 
One of the first things I'd like to do with my Neo1973 is to configure  
the GPRS connection to be always on.  
As I've understood, on the GSM level, the GPRS connection gets paused  
on text messages and incoming calls - but the GPRS call can still be  
resumed. On answering a call or making a call yourself, I take it that  
the GPRS call will get disconnected. Did I get this part right? Or is  
there a way to keep GPRS alive over voice calls? Or do text messages  
disconnect the GPRS connection?  
On the actual software level, I guess this means that PPP will get  
disconnected on voice calls, so the 'ppp0' device will go appear and  
disappear and possibly change IP-addresses on every disconnection as  
well. Is there any way to have the device survive disconnections?  
I ask this because there's going to be some complications from  
that. Firewall is no problem as it can be static, but QoS rules will  
need to be re-instantiated on if-up scripts. Also, any applications  
binding specifically to an interface will need to be able to handle  
the interface going up and down.  
My main goal is to have Neo1973 have internet connectivity at all  
times - but it would be nice to allow access to the internet via  
Neo1973 for other devices as well. However, this should not disrupt  
the connectivity for the device itself. So the device has to keep a  
private network for other devices and NAT the connections.  
USB-networking is probably no problem since it shows up as a normal  
ethernet device on both ends. But how to do Bluetooth networking? One  
choice would be to do Bluetooth PAN. This would require 'pand' and  
modules on the Neo1973 side. The device should be configured as a  
Bluetooth NAP, I guess. The other choice would be to use Bluetooth  
DUN. This would require running 'dund' and a PPP server on the  
device. Bluetooth DUN is quite a common use case for all sorts of  
mobile devices - Bluetooth PAN sounds like nicer setup though.  
So, I'm asking for input on these issues and I'm interestested as to  
how much of this is already available on the device and how much work  
would setting all this up be.  
Thanks in advance,  
-- Naked  

More information about the openmoko-devel mailing list