this would need to turn off your 3G device, while in 3G mode, if you like to swap between gsm modes there will be a new negotiation.

what about real throttling? is the 3G device scalable? is it possible to prevent the 3G from powering up while no connection is available? My 3G eats the battery when I have my phone at dead spots in my apartment, there it cannot establish >2G services but GPRS is still working. So if you scale down the 3G by software and have an automatic fallback to another technology (EDGE, GPRS, you name it) you wouldnt need to negotiate because of switching the network mode to something without 3.xG (GSM+GPRS+2G+3G+3.5G -> GSM+GPRS+2G). This could also help if no 3.xG network is available to reduce the frequency the 3.xG device is trying to establish services.

so on the one hand it could be a program managing services and on the other it could be simple settings of the services. the last one I would prefer! Depending on what network requests are pending, Xsec timeout, if after that time the deamon is still touched with new requests, the device decides to powerup 3.xG if active in the current mode. Or it scales down if no intense requests are pending anymore.
comments, please