"There are no plans for an enormous database which will contain the content of your emails, the texts that you send or the chats you have on the phone or online...."
Yeah, right.
From a technical perspective, the header logs are probably more useful than the content. Processing every email for content is iffy and very resource intensive. Let's not even touch on OCR for pictures included in Email and MMS... Dealing with the hundreds of different file structures for attachments? You're best off to scan for ASCII and just store everything for human review if the person does something later. However, tracking communication patterns (basically just the To and From, and the type of medium) is cheap and useful as hell. Any modern laptop can do that processing, and it's extremely useful.
I can give you a list of vendors that do the above stuff, if you like. Plenty of them make products that frankly suck. Functional, sure. They'll all hoover the information, but searching the data in a meaningful way? Oy. I only found TWO vendors that incorporate MD5 hashing for data integrity. I'm trying to convince the vendor to use both SHA1 and MD5 hashes to really make the product secure. I know, collisions are pretty f'ing rare, but it'd be trivial to implement.
