Digital signature, as an official signature, have many applications in information security, including authentication, data integrity, and non-repudiation. When a private or public document must be signed by a group of people, we call it multisignature scheme if all and every single member of the group signs the document. An identity-based digital multisignature is a multi signer digital signat...

The digital signature is one of the most important cryptographic primitives. It provides data integrity, message authentication and non-repudiation, which are required attributes in security critical services, such as electronic commerce, voting or health care. Whereas previous data formats for digital signatures concentrated on signing the entire document, the XML signature standard is feasibl...

Security of multimedia data is an imperative issue because of fast evolution of digital data exchanges over unsecured network. With the progress in data exchange by the electronic system, we need to secure information. In this paper 128 bit image encryption is used for securing the image. Many security issues are also concern with this exchange and sharing of information. These may be authentic...

An ad-hoc network is a self-configuring network of nodes (routers and hosts) connected by wireless links. The nodes are free to move randomly, organize themselves arbitrarily and the network's wireless topology may change rapidly and unpredictably. This freedom of routers and hosts to move in and out of the network creates security problems that are not seen in a wired network. This paper compa...

An undeniable mobile billing system allows a mobile network service provider to bill its subscribers with trustworthy evidences. Chen, Jan and Chen proposed such a billing system by introducing a trusted third party – Observer and exploiting a hash chain mechanism. In their system, the Observer provides call time evidence to both cellular carriers and subscribers for billing. In this paper, we ...

Certified e-mail is a value-added service for standard e-mail systems, in which the intended recipient gets the mail content if and only if the mail originator receives a non-repudiation evidence that the message has been received by the recipient. As far as security is concerned, fairness is one of the most important requirements. Recently, Galdi and Giordano (2004) presented an optimistic pro...

The B-POS (Bluetooth Point of Sale) is the prototype of a secure, mobile macropayment system. Since heterogeneous wireless network technologies such as PANs, LANs, and WANs have wellknown security weaknesses, it is mandatory to enforce security services, such as authentication, confidentiality, integrity, and non-repudiation. This article describes a Java-based macropayment system prototype fea...

A number of routing protocols has been proposed in recent years for possible use of Mobile Ad Hoc Networks in various application areas such as military, govt. etc. In this paper we have presented a comprehensive review of these protocols with a particular focus on their security aspects. Further we have presented a comparison of some of the existing Routing Protocols of MANETs. The base criter...

Mobile ad hoc networks are self organizing, infrastructure-less, low power networks, design to deploy bandwidth-shared radio channel communicat ion and to work under vulnerable environment. Security is primary concern in MANETs and in order to achieve high security (confidentiality, integrity, authentication, availability and non repudiation), several techniques have been exp lored in which b i...