This essay takes a look at a selection of network anonymity systems including VPNs, Tor, Freenet and I2P. The different systems are explained and then compared and contrasted with each other. A number of issues are considered for each system including ease of use, popularity, strength of anonymity provided, and potential attacks on the system.
You can download it from the following link: https://packetstormsecurity.com/files/download/140712/overview-of-network-anonymity-systems.pdf
Source: https://packetstormsecurity.com/files/140712/An-Overview-Of-Some-Popular-Network-Anonymity-Systems.html