In this paper, a VWC-system (Visual-based Watermarking Concealment System) is proposed.Besides the feature of watermarking system, the embedded information can hold the secret for the encryption key. This VWC-system works with frequency-domain watermarking technique, in conjunction with the concept of visual cryptography, in image processing. In the scheme, the embedded part is only a share which is a portion of the watermark generated from a chosen KFI (Key Feature Image) by visual cryptography. The rest shares which are not used in embedded procedure are kept until the extraction procedure in order to reveal the targeted secret or copyright watermark shown in the message of watermark image. This proposed VWC-system offers a new application and novel watermark embedding process, for practical cryptosystem applications, offering improved security.
Nowadays, GSM is used widely by people around the world. However, there are also some problems of GSM authentication to be found. In 2004, Choi et al. proposed an authentication scheme with user privacy protection in GSM. They claimed that their scheme can improve some drawbacks of GSM authentication and
achieve an ability of user privacy protection. But we point out that Choi et al.’s scheme is not able to achieve privacy and is not able to resist some well-known attacks completely. Hence, we propose a more efficient GSM authentication protocol with robust identity privacy protection. Our scheme also can remedy all drawbacks of GSM authentication mentioned by Choi et al. and resist to well-known attacks.
In wireless sensor networks, many sensor nodes form selforganizing wireless networks. The sensor nodes in these networks only have limited computation and communication capacity, storage and energy. In this paper, we propose a novel user authentication and key agreement scheme suitable for wireless sensor network environments. The main merits include: (1) the shared keys generation and management between all participants is flexible and simplified; (2) a sensor node only needs to register in a key center and can generate shared keys and exchange session keys with the other participants in the corresponding domain of the base station; (3) an installer can freely choose and change the password installed in a sensor node for protecting this node when it is installed or the battery of the node must be replaced; (4) the communication and computation cost is very low; (5) any two participants can authenticate each other; (6) it can generate a session key agreed by any two participants; (7) an installer can freely add new nodes to a sensor network
after some nodes have already been installed in it; (8) our scheme is a nonce-based scheme which does not have a serious time-synchronization
problem.
The authentication system is an important security element in a distributed computer environment. In 2006, Juang et al. proposed a robust and efficient password authenticated key agreement scheme using smart cards. They claim their scheme is robust and efficient. However, we find that their scheme can not prevent theoffline dictionary attack with the smart card perfectly. In this paper, we show this drawback and propose a new scheme to remedy the drawback.
This paper gives a new solution based on the varied Blom Scheme to resist attacks in the ad hoc network systems. Our scheme can efficiently set up the reliable communication links among all the nodes in any ad hoc systems.
In 2005, Zhang et al. proposed a novel authentication key agreement protocol for 3GPP-AKA protocol. They claim that their protocol can withstand the redirection attack, the attack in corrupted networks, and can solve the operational difficulty with the sequence numbers problem. In wireless communications, identity privacy is an important security issue we concern. There are two abnormal cases that a mobile station (MS) must send its real identity to a visited location register (VLR) when authenticating at location updating. One is that VLR can not verify IMSI of MS and the other is that VLR can not reach the previously visited VLR. We can find out that the identity of the user will be exposed when the adversary carries out the location privacy attack at location updating. For preventing the location privacy attack, users’ identities must be protected for 3GPP-AKA protocol. However, we point out that Zhang et al.’s improved 3GPP-AKA protocol is vulnerable to the location privacy attack, having higher space overhead on VLR, and having higher bandwidth consumption between HLR and VLR. In this paper, we propose an efficient authenticated key agreement scheme for 3GPP-AKA to overcome all
the drawbacks of Zhang et al.’s scheme.
In this paper, a packet construction mechanism using an ID-based factorial number structure (ID-based FNS) is proposed for a secure conference call system in an ad hoc network. We adopt the ID-based concept for a conference key generation in which each participant with one’s own public identity uses a pre-chosen secret-key to generate the exchange conference key for the conference call. Furthermore, due to the mobility of nodes in an ad hoc network environment, it is likely that some nodes quit or join during the operation of this conference. To solve these problems, we employ an information exchange table for each participant node in order to manage a secure conference call in an ad hoc network system. In addition, our scheme employs only one cryptographic algorithm of the secret-key system. The extraction of the secure sub-packets associated with each intended receiver is protected on the basis of the Diffie–Hellman key exchange protocol with the trusted public-key exchange. Therefore, the subsequent message recovery is successfully accomplished. This provides a new and feasible solution for a secure conference call in an ad hoc network system.
20 2007 Published by Elsevier Inc.
3rd year External Midterm Review Meeting (2009.01.07)
