Artin’s braid groups currently provide a promising background for cryptographical applications, since the first cryptosystems using braids were introduced in [2, 3, 18] (see also [22]). A variety of key agreement protocols based on braids have been described, but few authentication or signature schemes have been proposed so far. We introduce three authentication schemes based on braids, two of ...

With the emergence of ad hoc networking technology came efforts to provide necessary security support for ad hoc networks. However, due to challenging characteristics of ad hoc environments, providing the same level of security as in wired networks is often very difficult if not impossible. A more viable way to approach this challenge is to maximize the utility of the achievable security instea...

As mobile devices pervade physical space, the familiar authentication patterns are becoming insufficient: besides entity authentication, many applications require, e.g. location authentication. While many interesting and subtle protocols have been proposed and implemented to provide such strengthened authentication, there are very few proofs that such protocols satisfy the required properties. ...

Single authentication methods such as password, smart card, or biometric authentication suffer from their own weaknesses. Thus, combined authentication methods have been proposed recently. Unfortunately, even combined authentication methods are exposed to replay attacks, user impersonation attacks, server masquerading attacks, or stolen smart card attacks. To minimize the range of such attacks,...

Key management is fundamental to communications security, and for security in pervasive computing sound key management is particularly difficult. However, sound key management itself depends critically on sound authentication. In this paper we review current notions of entity authentication and discuss why we believe these notions are unsuitable for the pervasive domain. We then present our vie...

Entity authentication and key management mechanisms using symmetric cryptographic algorithms are examined. The particular protocols of interest are currently being progressed through ISO/IEC standardisation procedures. We reveal a number of misconceptions seen in a series of the draft standards documents. Due to these misconceptions several protocols supplied in the standards proposals are foun...

We introduce DigitalSeal, a transaction authentication tool that works in both online and offline use scenarios. DigitalSeal is a digital scanner that reads transaction information sent by an issuing entity of the DigitalSeal reader for authentication, and the information is encoded using a specially crafted bar-code. DigitalSeal views various pieces of transaction information for users to veri...

Digital signature methodology provides cryptographic services like entity authentication, authenticated key transmission and authenticated key agreement. A Digital Signature is used to provide authentication, non-repudiation & integrity over the digital data in data exchanged and to validate the recipient for the authorized identity over open network. The goal of a Digital signature algorithm i...

Digital certificates (through the use of publickey cryptography) provide an entity the power to authenticate users even when the CA (Certification Authority) that issued the certificate is not on line. This authentication mechanism is widely used today in Virtual Organizations (VOs) to distribute the weight of the authentication. However, as shown in this paper, the use of public-key cryptograp...

So far, all solutions proposed for authenticated key agreement combine key agreement and authentication into a single cryptographic protocol. However, in many important application scenarios, key agreement and entity authentication are clearly separated protocols. This fact enables efficient attacks on the näıve combination of these protocols. In this paper, we propose new compilers for two-par...