Points that any security intelligence bureaucrat (with the IQ of a turnip)
would point out.
1. Most major world powers have security intelligence agencies that
traditionally buy the latest and greatest consumer gear (were special gear
is not required).
2. Most modern recorders are digital -- digital to disk, typically hard
disk.
3. For review at HQ (at least to program the ECHELON computers for keywords
and phrases), any analogue tapes would have to have been digitized anyway.
3A. I would almost assume that secure FTP would have been used to send the
data to HQ.
4. Digital copies of anything involving security matters will tend to be
preserved as a matter of course for seven years -- and security intelligence
agencies keep secrets for 50 years as a matter of standard procedure.
4A. In the modern security intelligence agency, your librarian is perhaps
more of a key person than your analyst. Primarily because modern
intelligence agencies keep far more data than is necessary. Note: most
security intelligence agencies would get an 'F' grade when it comes to
processing and correlating historical information -- mainly due to bulk data
retention issues (where no further data mining takes place).
4B. In order to process fully all incoming data correctly, the CIA (for
example) would probably need a staff of 10 million people.
5. The moral: a consummate Austro-Hungarian bureaucrat (or maybe Kafka)
could best explain the life cycle of data within most of the world security
intelligence agencies. You don't need a modern explanation to see or
understand the flow (and eventual disposal) of intercepts.