Quote from: Shannon on August 11, 2012, 08:08 amjoy, rfid backscattering can be easily detected, if the design itself was open source or mass produced then customs could scan only for the specific fingerprint this device would make, leading to a 100% interception rate on packs with theseI reluctantly came to the same conclusion.@Joy, it's something you just have to roll your own on. A standardized solution would weaken our strategic advantage swarming gives us. "Diversity is Strength" (!) (shades of a sort of inverse Big Brother there, Big Sister to the rescue!)If we all put light sensitive equipment in packages, eventually customs will be opening packages inside special darkrooms. There is no point in allowing an adversary to evolve a defense unless your plan was to throw the more naive vendors to the dogs as cannon fodder down the road. Although postal inspectors are not stupid, they fundamentally operate with reactionary stratagems like package profiling, as does the state in general e.g. trying to block Tor or strong crypto.To be honest I'm not sure how smart it is to be using GSM inside packages going through the postal system. I can very easily imagine a postal inspector thinking "Well, shit, this could be a IED, had better call bomb disposal crew" and soon there's an inquisitive little robot trundling towards your package in a blast pit (I feel sad when they get blown up in movies like Hurt Locker, they seem so friendly! :-) )IMHO passive RFID or active RFID tags that have a little power source daemon to tell themselves when to turn on are the best bet. Like how a CMOS battery ensures the computer knows the time the next time you wake it up, but only checked periodically somehow. I must admit I haven't done a vast amount of research in this area but it's little projects like these that could give you a decisive edge over the competition a while down the road if you were shipping larger than normal quantities.In theory active RFID can reach a range of 100 meters (emphasis on *theory*), which makes them ideal for detecting a dead drop that's gone amiss. You could hypothetically simply drive past on a completely different street to check the drop hasn't been compromised. Such technology seriously breaks LE balls.