Re: Re: "SIGINT tradecraft…is very hands-on (l i terally!)"

jim bell jamesdbell9 at
Wed May 14 11:23:50 PDT 2014

From: stef <s at>

On Wed, May 14, 2014 at 09:03:50AM -0700, jim bell wrote:
> I guess I'm still not being clear.  It would be my way of objecting to a court's ordering the telecom company that
>I might work for (or, one day, that I might own?!?) to present an "electronically-readable" form of the telephone >metadata of millions of telephones.  The judge ordered that; my sneaky response would be to generate an >"electronically-readable" file, basically a pdf file or a series of same, itself with an image that looks like >"captcha" information:  relatively easy for a human to read, but rather difficult for any computer to turn into >easily-useable (searchable) information.  In other words, the information would be presented to the NSA, but it >would be essentially unuseable without being (first) human-decoded.
>assuming this is correct:
>then googlestreetview tech is better at solving captchas than humans.

For a single, tiny piece of "captcha", that might very well be true.  But suppose the telephone metadata information for a billion phone calls per day is turned into "captcha's".  How much CPU power would the NSA have to apply, each day, just to back-convert that metadata into computer-searchable form?  Admittedly, that's irrelevant:  The NSA would simply ask the court to order the company to stop being a wiseass, and to stop using the captcha technique.  
        Jim Bell
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