Earticle

Until now, the interests of the research about sensor network security have been focused on the security services that provide authentication, confidentiality, integrity, and availability. However, the interest in the issue of actual identifier's exposure of sensor node is rapidly increasing. Also, the interest in the efficiency of creating encryption key that is used for the sensor network is increasing. Many schemes for providing node's anonymity in the existing Ad-Hoc network were suggested, but these schemes are not appropriate for sensor network that is energy-limited, so a scheme for providing anonymity that is suitable for sensor network's characteristics is required. Also, Sensor network maintains high limitation of resource because it performs many communications in order to create encryption keys. To solve these problems, this research suggests LA2EP Protocol. LA2EP Protocol can minimize resource and provide a new scheme for authentication and encryption that can provide anonymity of node for safe communication. To analyze the performance of the suggested protocols, a degree of anonymity that is provided by the scheme suggested by using an Entropy-based modeling was measured. As a result, when the suggested scheme was used, the degree of anonymity of sensor node was high. It showed that an important element to increase the degree of anonymity was to let the sensor's ID not known correctly. Also, as a result of calculating spaces for operation, communication, and storage while considering the characteristic of sensor network, which is limited in resource, it showed suitability for sensor network environment.

In this work, we design a method for efficient revocation within Ciphertext-Policy Attribute-Based Encryption scheme. Our main technical innovation is based on linear secret sharing and binary tree techniques, every user in system is assigned with both a set of attributes and a unique identifier. Any user can also be efficiently revoked by using this identifier. Furthermore, this technique resulted in two key contributions: the size of the cryptographic key material is smaller and encryption/decryption cannot be affected with an unbounded number of revoked users. Then, the scheme is proved to be secure under the q-MEBDH assumption in the standard model. The efficiency is also optimized that the size of user’s private key has only a constant increase. The revocation information is embedded in the ciphertext so that the fine-grained access control is more flexible.

CCSDS Standard is widely used in the international space telecommunication area. But standard recommendation of CCSDS is not restrictive, so, we can select an appropriate encryption protocol among the layer. For synchronization, encryption sync is attached in the beginning of the encrypted data. In the exceptional environmental condition, although the receiver can not decrypt the normal data, the sender have no conception of that situation. In this paper, we propose a two-stage SES alarmed link encryption synchronization method having optimized threshold value necessary to decide whether the receiver has a correct decryption or not. first, through the experiment of mutual relations between error rate and encryption synchronization detection error, we can predict worst communication environment for the selected encryption synchronization pattern. second, through the experiment for finding what number of consecutive frame synchronization error is an appropriate reference value and analysis of that experiment, we suggest an optimized threshold value for resynchronization request. lastly, through the output images we can predict the probability error that should be guaranteed by channel coder.