Espionage Techniques: Category

A

Agent provocateur

B

Backdoor (computing)
Black bag operation
Black-bag cryptanalysis

C

Cell phone tracking
Canary trap
Compartmentalization (intelligence)
Concealing something in a book
Concealment device
Covert listening device
Cryptography
Cut-out (espionage)

D

Dead drop
Disinformation

E

Eavesdropping
Espionage balloon
Exfiltration

F

Fiber tapping
Forgery
Front organization

H

Honeypot (espionage)

I

Infiltration tactics
Interrogation

L

Letter beacon

N

Network analysis

O

One-way voice link

P

Postal interception
The Purloined Letter Approach

R

Rubber-hose cryptanalysis

S

Secret broadcast
Secure communication
Sleeper cell
Spy satellite
Spy ship
Spyware
Steganography
Surveillance

T

Technical research ship
Telephone tapping
Tradecraft

U

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