On Fri, Jun 05, 2009 at 10:37:49PM +0200, Harald Welte wrote:
So IMSI ATTACH/DETACH really is about a SIM(IMSI) being activated/deactivated in a given LA. activation/deactivation typically is switching the phone on or off.
In other words: IMSI ATTACH/DETACH is only used in addition to regular Location Update, and it is used in situations where a MS on a network with ATT=0 would not perform any signalling with the network at all.