Since the earliest days of necessity for secret transmission of messages, which date back to thousands years BCE, different methods have been used to transfer the message between two parties. These days, systematic ways for transmitting secret information are used, and the fear of cracking the message is increasing with the development of breaking algorithms for different encryption techniques....

Wireless Sensor Network (WSN) consists of huge number of sensor nodes which are small and inexpensive with very limited resources. The public key cryptography is undesirable to be used in WSN because of the limitations of the resources. A key management and predistribution techniques are required to apply the symmetric key cryptography in such a big network. Many key predistribution techniques ...

Broadcast encryption is the process of delivering encrypted data through a secure channel, intended for multiple users, in which only the privileged users can decrypt the content. In a broadcasting system, all the intended recipients are required to be accommodated in an organized way, which is possible through an efficient key management scheme. An ideal Broadcast Encryption scheme should defi...

Securing a wireless communication has generally a vital importance, particularly when this communication is in a hostile environment like in wireless sensor networks (WSNs). The problem is how to create cryptographic keys between sensor nodes to ensure secure communications. Limited resources of sensor nodes make a public key cryptosystem such as RSA not feasible. So, most solutions rely on a s...

Multicast is an efficient technique to distribute data to a large group of users. To prevent disclosure of distributed data to unauthorized users, multicast-based applications require confidential group communication, which is achieved by encrypting data with a group-wide shared key. The group key must be updated and redistributed to all authorized users in a secure and reliable fashion wheneve...

In the secure group communication, data is transmitted in such a way that only the group members are able to receive the messages. The main problem in the solution using symmetric key is heavy re-keying cost. To reduce re-keying cost tree based architecture is used. But it requires extra overhead to balance the keytree in order to achieve logarithmic re-keying cost. The main challenging issue i...

This paper proposes a scheme to provide security to dynamic multicast VoIP systems efficiently. Security is usually provided by encrypting the media packets sent from a user to other users with the help of a shared key called the session encryption key. The most time consuming process in a dynamic multicast VoIP environment is the group key management. Whenever there is a change in the group me...