NSA spying: What's the best phone encryption & IMEI random number generator?

It is also not correct.

However, in a number of countries stolen handsets will be registered and the operators will refuse service to stolen handsets.

You shouldn';t be able to change your IMEI but only because you shouldn't change the serial number (so it is pointless to have it stolen) Except, of course, many stolen handsets are exported.

Casper

First off, nobody here is talking about stolen handsets; and secondly we're talking about the USA only (at least I was).

Regarding stolen handsets in the usa, my handset was stolen (well, actually, I left it in a cafe, but someone took it) and the telco did absolutely nothing about it.

And, as I said from the start, in the USA, it's not illegal to change the IMEI (probably for the same reason that they do nothing about stolen handsets).

Anyway, I got my answers on how to change the IMEI and I'm working on the details. Thanks.

As for the encryption - the answers were good - but too deep for me.

I wouldn't say meaningless because if your fone is stolen and you know the IMEI they can block any fone with this EMEI from registering on to their network. Of course there is nothing stopping them from going to another GSM / WCDMA carrier and using it unless there is a common stolen fone database running between carriers..

It depends *how* 'meaningless' "nearly meaningless" *really* is.

For example, as (IIRC) Jeff said, from the IMEI your provider knows which exact phone model you're using.

If I put my SIM in another phone, my (account on my) provider's website will show which brand and model phone I'm using, while I've never told them. They will also send the messages to configure the Internet and MMS setup of the phone, which (AFAIK) are brand/model dependent.

So a forged/bogus/unused IMEI is exactly that. Whether it's "nearly meaningless" is up to the NSA. :-)

Try dealing with a carrier to return a phone you found. They have zero interest. Every phone I found I returned by calling the recent phone numbers until I found someone who knew the owner.

I never found a locked phone.

I used the 3D Applicon mechanical system on a DEC PDP-11/34 do design microwave radios in about 1982. I used the pen and tablet to do the gesture thing, but found the menu picker tablet overlay thing easier to learn. Everyone had a gesture cheat sheet taped to their monitor as there were just too many gestures to remember.

They don't want the other fishermen to know if they're catching fish or where they're located. Any fishing boat stupid enough to announce their position and their catch is likely to find themselves in very crowded waters.

We have a chronic problem with one of the sheriff repeaters. One of the European marine frequencies just happens to land on the repeater input. When the cruising commercial fishing boats arrive in the area, the repeater is polluted with scrambled audio. Fortunately, it's only in the early morning, when the fish are active. It became a sufficiently irritating problem that some official managed to get the FCC enforcement burro involved. That turned into a farce, and did nothing useful.

Phil Zimmermann (author of PGP) has a new company: Again, note that the encrypted smartphone calls are made over the data channel, not the voice channel.

Mostly correct. In theory, the GSM vendor would not need to know the IMEI number. Reality is quite different:

1. The SIM card identifies the owner and stores his data. However, if the phone is vendor locked, it ties the SIM ID to the IMEI, effectively making it impossible to move the SIM card to a different phone. A less draconian vendor lock looks at only the vendor, model, and service provider parts of the IMEI, and just locks the SIM to those numbers. That allows the dealer to replace one smartphone, with a similar model, and not have to update the SIM.
2. The IMEI defines the maker and model of the phone, and it's features. If those demonstrate that the phone is a smart phone, the vendor tacks another /month onto the bill for data service, even if it wasn't requested or ordered. I did this by accident. I picked up a basic phone that someone had hacked with the IMEI for an iPhone 3G. I didn't recognize the problem. When I activated the phone for a customer, I found a data service charge tacked onto their bill. The phone wasn't worth hacking, so I just changed to a phone, with a real IMEI number. However, the /month didn't disappear from the online billing summary until after I called customer service three times.

I don't do T-Mobile, so I have no idea what might happen. Sorry.

Such databses exist between carriers in some countries, but I don't think there is an international shared database of stolen phones.

Casper

That is not correct: the firmware in the phone checks whether the SIM is from a particular operator; it is locked to the operator and not to the SIM card.

Interesting. It is probably listed in the "small print" but that would also mean that the operator will frowned upon change IMEIs.

Casper

True. There is no processor on the SIM card so that comparison has to be done by the phone firmware. However, my point was that the vendor lock can be by the specific phone, by the cellular vendor, or by the phone manufacturer, depending on how much of the IMEI number is used. - Mobile country code (MCC; e.g., will only work with SIM issued in one country) - Mobile network code (MNC; e.g., AT&T Mobility, T-Mobile, Vodafone, Bell Mobility etc.) - Mobile subscriber identification number (MSIN; i.e., only one SIM can be used with the phone)

Apple and AT&T were the first to require a mandatory data plan. If you activated an iPhone, you were required to have a data plan. Since there were few protests by those who didn't want the data plan, the other vendors did the same thing almost immediately. I complained on the Verizon support site, and soon found both my postings and account had been removed by VZW. After about 6 months, Verizon extended the mandatory data plan to newer smartphones, eventually dividing their selection between "feature phones" and "smart phones". Again, there was little protest, so the other vendors did much the same thing. The Verizon MVNO's were more flexible and would activate smartphones without data plans, so all was not lost. However, this wasn't to accommodate disgruntled users, such as myself, but rather because Verizon would not allow the MVNO's to use their latest data service. For example, Page Plus Cellular will only do 3G data, not 4G. Before Verizon built their 4G system and only had 3G, the MVNO's could only use EVDO or 1XRTT.

However, soaking customers for a mandatory data plan wasn't sufficient for VZW. They often billed customers for accidental use of the data service. In the early days of smartphones, it was not unusual for customer to not know that their phones had internet data service, much less how to use it. If I bought a smartphone with data capability, but didn't subscribe to the monthly data plan, I would be charged some rediculously high rate for moving a few bytes if the phone decided to do a lookup or update check. Many phones had no obvious way to disable data service. Intitally, VZW also obfuscated the charges on the bill and didn't properly explain the charges when the phone was activated. That resulted in lawsuits and FCC action: The continuation and expansion of the mandatory data plan was allegedly a result of this action. Never mind that it would have been trivial for VZW to block all data traffic by IMEI and be done with the problem.

The Applicon had such a ridiculously large menu that you have to wonder why they bothered with gestures. Like what did it save? The companion plotter was that "air hockey" thing. Xynetics?

T-mobile took the opposite idea. Well sort of. They cuts the minutes down to nothing (100 min), but added a decent data plan (4G, but only half at the full LTE speed), the rest at their crappy 4G, all for $30.

The T-mobile 4G would be fast enough, but the latency is noticeable. Easily over 100ms. LTE is simply amazing. About 35mbps down and 15mbps up with no discernible lag.

The Applicon menu system was not very heirachial. It had maybe two levels (2D, 3D, and I/O). Effectively, it was flat menu system with thousands of commands and jestures. I drew most of the lines from the command line. It was easier than trying to draw on the screen.

One big problem for me was that most of what I was doing on the 3D CAD system was not authorized. Officially, I was using the CAD system after hours to "learn" how to use the system. Instead, I was brainstorming and designing the next generation of products. One of the VP's drifted by every few evenings to look over my shoulder and ask questions. Somehow, I forgot to mention that what I was doing was NOT what the company was going to be producing. He liked what he saw and was furious when he discovered that the real product looked more like the traditional rack mounted behemoth. I later implimented those ideas for other companies.

Yep. Xynetics. I don't recall which model. We later got a vertical bed pen plotter, that saved on floor space. Somewhat later, there was a Xynetics bed plotter at Intel, Santa Cruz that occupied most of a room. Offhand, I would guess a 6x15ft bed. I have no idea how they got it in and out of the building. Probably in pieces. Nice white formica surface, perfect for air hockey.

I called "hubby" from the directory and when someone answered, I said "I think I have your wife's phone".

Another phone that I found had a dead battery, so I took it to the proper company store. They wouldn't even plug in a charger, and had no interest at all in finding the owner.

Same thing with a working iPod. Apple had no interest in finding the owner.

Yep, except that I was collecting them. At one point, I had about 10 of them with various interfaces and power systems. Cheap printers that generated no RFI for VHF and HF packet radio. Very easy to refill the ink carts. I used the HP-IB version on some of my test equipment for screen and diagnostic dumps. I think I paid about $15/ea.

Uh, assuming they would print! That was the problem with the stinkjet. We threw away about 50 or so.

I think in the stinkjet era we used HP pen plotters.

The record will show that, at least in the USA, the carriers have absolutely no interest in blocking stolen phones.

They won't do anything - as you can see from mine and other posts.

So, from _that_ perspective, the IMEI is a meaningless set of numbers.

Hi Jeff, In practice, at least with both AT&T and T-Mobile, you can swap your SIM card into as many phones as you like, and they'll all work. AT&T requires you to "tell" them what your IMEI number is initially and T-Mobile doesn't even ask what the IMEI number is. Either way, you can still swap the SIM card into as many phones as you like, and they don't care (from an account-identification purpose).

Hmmm... I've moved my SIM card to a whole bunch of phones, over the years, and within my family, I swap SIM cards among phones, and I teach my kids how to call me from their friends' phones when their batteries are dead, simply by swapping the SIM card. So, in practice, the only thing that's difficult is switching carriers; not switching phones.

This added "data" fee is only done by AT&T. T-Mobile has no such automatic data fee. That fee is the reason I dropped AT&T in favor of T- Mobile in the first place, so, I know this inside and out. There are so many misconceptions revolving around the IMEI.

I don't claim to be an expert, but, at least with T-Mobile, the IMEI is (nearly) meaningless; and it's only meaningful from the standpoint of charging you extra by AT&T.