I'd recommend Understanding Surveillance Technologies: Spy Devices, Privacy, History & Applications by J.K. Petersen. The book is thick but the historical info is good albeit dated. Covert Surveillance: The Manual of Surveillance Training by Peter Jenkins is also a good book for less technological means of surveillance. "Countering Hostile Surveillance: Detect, Evade, and Neutralize Physical Surveillance Threats" as well as "Surveillance Countermeasures: A Serious Guide To Detecting, Evading, And Eluding Threats To Personal Privacy" by ACM IV Security Services are great books on the counter surveillance side of things. Silent Warfare: Understanding the World of Intelligence by Abram Shulsky and Gary Schmitt has been highly recommended to me but I haven't gotten a copy yet. The link in my sig gives good insight into internet SIGINT.
Sweeping for covert listening devices (CLD) is not simple and be ready to spend tens of thousands of dollars on test equipment to properly screen for CLDs. Simple toys that you get out of spy catalogs (or make if you are competent) can do basic detection against cheap crap but when faced with a competent enemy things get much more difficult and expensive. For example
a nonlinear junction detector (NLJD) can cost well over $10K and doesn't include the equipment you are going to need to verify what the NLJD dectected (metal detector, x-ray, et al.) Good spectrum analyzers are several thousand easily.
Obviously, where possible, any device capable of transmitting signals (cellphone) should be left at home when committing any crime. I recently watched a program featuring two drug dealers, one of whom butt dialed 911 while talking about a shipment of drugs. CLDs are irrelevant in an age when everyone carries around a device capable of transmitting audio and video.
Aside from the obvious the biggest SIGINT threat I see for people like us is the use of a signalling device inside a package being delivered as part of a CD. In
another post I have indicated the police are using this tactic.
Rick Collins said:
Given the headaches presented by savvy suspects, law enforcers are taking a new approach: wiring the package to signal when it's opened. When someone opens a package, that's good evidence that he's the one who knowingly intended to possess it, right? It might even be stronger evidence than signing for it. The application for the search warrant will request authorization to execute the raid once the signal goes off. Several jurisdictions have begun using electronic signaling devices, typically AT-4's, to confirm that a target has opened his package. No part of the device is visible unless the package is opened. It makes no audible sound but transmits an alert signal to a remote receiver manned by the agents. These devices are perfect in cases where a signature request might spook the target. An AT-4 can make the difference between a botched operation and a valid arrest and raid. Be aware that it's likely the wave of the future.
A simple way to prevent signal leaks (like from a CLD or tracking device used during a CD) is to construct a Faraday cage. Anyone interested in SIGINT should already know about this and even if you don't just Google it or watch Enemy of the State. Magic bags are basically portable Faraday cages designed to block RF signals from tags. Similar designs could be deployed to prevent signal leakage from cellphones. Obviously it would be necessary to test for signal leakage before deploying such a device.
Anyone in need of a rf jammer would be better off constructing it themselves since they are laughably simple devices (assuming your target isn't
proactively scanning for jamming signals.) Expect a serious FCC fine and/or up to a year in jail if you are caught using one (think triangulation). Though to be honest I can't see any practical application of a cell jammer for a grower. Maybe if you want to rip off a jewelry store since many alarm companies seem to use the existing phone and cellphone infrastructure for sending out alarms, but not for growing.
There is always the risk of catching LEO authored malware like CIPAV. Throwaway computing is a good idea to help prevent this. The
TAILS live cd[url] comes to mind. Having a computer that is never connected to the internet for storing/decrypting sensitive files is a good idea.
Also as much as I like SIGINT it's the HUMINT people like us have to worry about.
Things like [url=http://eckbox.sourceforge.net/]van ecke phreaking and
other forms of signal interception are scary. However police officers are not trained to use these tactics. Why should they when HUMINT has proven so fruitful. Undercovers and CIs are the bread and butter of drug cops. Most low level drug networks organize themselves in ways that leave them highly vulnerable to HUMINT attacks. Many even rely on a primitive face-to-face topology which is suicidally dangerous for all involved and quite frankly stupid to an extreme (though someone is going to have to take the risk of dealing small quantities in person due to the cost of running more sensible networks and the relatively low margins involved). The DEA wont be using expensive lasers when they have cheaper paid informants who will make just about any claim they want. I'd also like to mention that if you are close enough to the other person to talk with them you have problems bigger then window vibrations.