ing nonces by constants, an unbounded execution of the NeedhamSchroeder protocol can be represented by the following set CNS of clauses: ⇒ I(enca(〈na, a〉, pub(i))) I(enca(〈x, a〉, pub(b))) ⇒ I(enca(〈x, nb〉, pub(a))) I(enca(〈na, y〉, pub(a))) ⇒ I(enca(y, pub(i))) For simplicity, we have only described the clauses corresponding to the case where A starts sessions with a corrupted agent I and B is w...

Specifications for security protocols range from informal narrations of message flows to formal assertions of protocol properties. This paper (intended to accompany a lecture at ETAPS ’99) discusses those specifications and suggests some gaps and some opportunities for further work. Some of them pertain to the traditional core of the field; others appear when we examine the context in which pro...

recently, baghery et al. [1, 2] presented some attacks on two rfid protocols, namely yoon and jung et al. protocols, and proposed the improved version of them. however, in this note, we show that the improved version of the jung et al. protocol suffers from desynchronization attack and the improved version of the yoon's protocol suffers from secret disclosure attack. the success probabilit...

Despite the importance of proofs in assuring protocol implementers about the security properties of key establishment protocols, many protocol designers fail to provide any proof of security. Flaws detected long after the publication and/or implementation of protocols will erode the credibility of key establishment protocols. We examine the class of key agreement protocols (without proofs of se...

Security protocols flaws represent a substantial portion of security exposures of data networks. In order to evaluate security protocols against any attack, formal methods are equipped with a number of techniques. Unfortunately, formal methods are applicable for static state only, and don’t guarantee detecting all possible flaws. Therefore, formal methods should be complemented with dynamic pro...

Recently, two certificateless three-party authenticated key agreement protocols were proposed, and both protocols were claimed they can meet the desirable security properties including forward security, key compromise impersonation resistance and so on. Through cryptanalysis, we show that one neither meets forward security and key compromise impersonation resistance nor resists an attack by an ...

This thesis includes my research on efficient cryptographic protocols, sensor network key management, and radio frequency identification (RFID) authentication protocols. Key exchange, identification, and public key encryption are among the fundamental protocols studied in cryptography. There are two important requirements for these protocols: efficiency and security. Efficiency is evaluated usi...

Wireless local area networks (WLAN) are beginning to play a much larger role in corporate network environments and are already very popular for home networking applications. This increase in accessibility has created large security holes for hackers and thieves to abuse, that is finally being addressed by stronger security protocols and these security protocols include Wired Equivalent Privacy ...

in mobile ad hoc networks, the absence ofinfrastructure and the consequent absence of authorizationfacilities impede the usual practice of establishing a practicalcriterion to distinguishing nodes as trusted and distrusted.since all nodes in the manets would be used as router inmulti-hop applications, secure routing protocols have vital rulein the security of the network. so evaluating the perf...

Key agreement protocols are essential for secure communications in open and distributed environments. Recently, identity-based key agreement protocols have been increasingly researched because of the simplicity of public key management. The basic idea behind an identity-based cryptosystem is that a public key is the identity (an arbitrary string) of a user, and the corresponding private key is ...