Title
CAPTCHA: Machine or Human Solvers? A Game-Theoretical Analysis
Abstract
CAPTCHAs have become an ubiquitous defense used to protect open web resources from being exploited at scale. Traditionally, attackers have developed automatic programs known as CAPTCHA solvers to bypass the mechanism. With the presence of cheap labor in developing countries, hackers now have options to use human solvers. In this research, we develop a game theoretical framework to model the interactions between the defender and the attacker regarding the design and countermeasure of CAPTCHA system. With the result of equilibrium analysis, both parties can determine the optimal allocation of software-based or human-based CAPTCHA solvers. Counterintuitively, instead of the traditional wisdom of making CAPTCHA harder and harder, it may be of best interest of the defender to make CAPTCHA easier. We further suggest a welfare-improving CAPTCHA business model by involving decentralized cryptocurrency computation.
Year
DOI
Venue
2018
10.1109/CSCloud/EdgeCom.2018.00013
2018 5th IEEE International Conference on Cyber Security and Cloud Computing (CSCloud)/2018 4th IEEE International Conference on Edge Computing and Scalable Cloud (EdgeCom)
Keywords
Field
DocType
CAPTCHA,Machine Solver,Human Solver,Computer Security,Game Theory,Economics,Cryptocurrency,Blockchain,Bitcoins
Countermeasure,Web resource,Computer security,Computer science,Server,Hacker,Software,Business model,CAPTCHA,Cryptocurrency
Conference
ISBN
Citations 
PageRank 
978-1-5386-6449-0
0
0.34
References 
Authors
12
2
Name
Order
Citations
PageRank
Zhen Li1233.69
Qi Liao29712.60