Version 1.2 We introduce honey encryption (HE), a simple, general approach to encrypting messages using low min-entropy keys such as passwords. HE is designed to produce a ciphertext which, when decrypted with any of a number of incorrect keys, yields plausible-looking but bogus plaintexts called

, that the corresponding plaintext satisfies some a priori relation (to prevent sending bogus messages). Finally, in case of a dispute, the identity of the intended receiver can be recovered by a designated authority. In this paper, we abstract a generic approach to construct group encryption schemes. We also introduce

Kerberos was initially developed at MIT as a part of Project Athena and in these days it is widely deployed single sign-on protocol that is developed to authenticate clients to multiple networked services. Furthermore, Cross-realm authentication is a useful and interesting component of Kerberos aimed at enabling secure access to services astride organizational boundaries. Also, Kerberos has continued to evolve as new functionalities are added to the basic protocol and one of well-known these protocols is PKINIT. First, I review and analyze the structure of Kerberos recently proposed and the cross-realm authentication model of Kerberos. Also, I discuss PKINT, an extension version of Kerberos, which modifies the basic protocol to allow public-key authentication. Although Kerberos has been proven its strengths so far, it also has a number of limitations and some flaws. I dedicate my efforts to an analysis of PKINIT and mainly focus on a number of vulnerability, flaws and attacks lately discovered on Kerberos as well as PKINIT in this paper. Lastly, I introduce several possible solutions to

Users regularly experience a crisis of confidence on the Internet. Is that email truly originating from the claimed individual? Is that Facebook invitation indeed from that person or is it a fake page set up by an impersonator? These doubts are usually resolved through a leap of faith, expressing the desperation of users. To establish a secure basis for Internet communication, we propose SafeSlinger, a system leveraging the proliferation of smartphones to enable people to securely and privately exchange their public keys. Through the exchanged authentic public key, SafeSlinger establishes a secure channel offering secrecy and authenticity, which we use to support secure messaging and file exchange. Essentially, we support an abstraction to safely “sling ” information from one device to another. 1 SafeSlinger also provides an API for importing applications’ public keys into a user’s contact information. By slinging entire contact entries to others, we support secure introductions, as the contact entry includes the SafeSlinger public keys as well as other public keys that were important. As a result, SafeSlinger provides an easy-to-use and understand approach for trust establishment among people. 1.