The Research Of Password Protection Based On Threshold Secret Sharing

With the advancing process of social informationalization,Internet plays a more and more important role in mankind's daily life.In the information age,people just need to input their accounts and passwords to get access to the related application in most cases.If the user's password has been stolen.then the private data of his account will be leaked immediately.Therefore,the protection over the user's password is showing its importance.Usually the user's password is hashed by the hash function and then stored in the password files.However,those files are often stolen by online attackers.Meanwhile,it becomes much easier for attackers to crack the hash value with the growing calculating ability of computer,which causes more and more password data leakage.So how can I secure users' password data under such a condition?In the paper,we design a distributive password protection system,called Phoney.In Phoney,we study the question how to protect password on the condition that users input their account and password to pass authentication.In Phoney,the threshold secret sharing is applied to encrypt the user's password hash.In this case,the hash stored on the server is not the original one.Thus attackers are unable to crack the password by using the customary method.The threshold cryptosystem can be unlocked by users with certain authority.If the attackers happen to crack the threshold cryptosystem,Phoney will use false passwords(honeywords)to confise them so that their probability of success will effectively lowered.In the paper,the relevant background and recent studies,which analyze the advantages and disadvantages of several ways,will be displayed.Then the basic thoughts,ideas and theories together with some examples will be introduced,which laid a good foundation for the understanding of the threshold cryptology.Later the paper introduces the false password technique.The detailed description and usage of honeywords put forward by Ari Juels are the emphasis of the paper.Then,I design Phoney which combines the threshold cryptology and honeywords technique.We analyze the systematic organization to explain the process of data storage,the authentication of users,the unlocking of the encrypt system and how to create new account and to change the passwords.After that,we use the Python programming to design a proto-system.The designing process of the system and key technique have been analyzed.In the end,we make an analysis over its time consumption,the cost of storage and its safety.According to the experimental results,Phoney causes no distinct changes in time consumption and storage cost,while it improves the safety greatly.