Fair Micropayment System Based on Hash Chains

Micropayment schemes usually do not provide fairness, which means that either the customer or the merchant, or both, can cheat each other and gain a financial advantage by misusing the protocols. This paper proposes an efficient hash chain-based micropayment scheme, which is an offline, prepaid scheme that supports simpler divisibility of digital coins. In the execution of payment protocol, the customer’s dis- bursement and the merchant’s submittal are performed step by step, whoever cannot gain addition profits even if he breaks off the transaction. The hash chain can also be used for transactions with different mer- chants. Unlike other micropayment schemes, e.g., PayWord, no public-key operation is required,which im- proves the efficiency. The scheme also provides restricted anonymity.

Performance optimization for multicast packet authentication

In secure multicast, one of the challenging problems is the authentication of multicast packets. This paper presents a novel scheme to address this problem, which combines ideas in both the hash tree schemes and the hash chain schemes. In this scheme, a group of packets is partitioned into equal-sized subgroups. Then a Merkle hash tree is built for each subgroup of packets, and the hash value of every root is appended to preceding packets to form hash chains. Its performance is analyzed and simulated using Biased Coin Toss loss model and 2-state Markov Chain loss model, respectively. Compared with the original hash chain schemes, results show that this scheme is much more efficient in term of communication overhead.

An Authenticated Dynamic Key Management Scheme for Clustered Sensor Networks

Secure sensor networks has received much attention in the last few years.A sensor network always works unattended possibly in a hostile environment such as a battlefield.In such environments,sensor networks are subject to node capture.Constrained energy,memory,and computational capabilities of sensor nodes mandate a clever design of security solutions to minimize overhead while maintaining secure communication over the lifespan of the network.In this paper,an authenticated dynamic key management scheme,ADKM has been proposed.It provides efficient,scalable,and survivable dynamic keying in a clustered sensor network with a large number of sensor nodes.ADKM employs a combinatorial exclusion basis system (EBS) for efficiency and one-way hash chains for authentication.Analysis of security and performance demonstrate that ADKM is efficient in security of sensor networks.

Anonymous authentication protocol for multi-services in wireless environments

To provide mutual authentication among users, wireless networks, and service providers in roaming wireless environments, this article presents an anonymous authentication and access control protocol. Bases on this protocol, entities of different trusted domains can mutually authenticate each other and preserve the anonymity of users. Hybrid cryptosystem, secret splitting, and hash chains are used in the protocol, which decrease computational loads and establish trusted relations for both entities. The proposed protocol has the least computation complexity compared with other protocols, whereas, the security has been significantly improved.

Efficient User Authentication and Key Management for Peer-to-Peer Live Streaming Systems

Recent development of the peer-to-peer （P2P） live streaming technique has brought unprecedented new momentum to the Internet with the characters of effective, scalable, and low cost. However, before these applications can be successfully deployed as commercial applications, efficient access control mechanisms are needed. This work based on earlier research of the secure streaming architecture in Trust- Stream, analyzes how to ensure that only authorized users can access the original media in the P2P live streaming system by adopting a user authentication and key management scheme. The major features of this system include （1） the management server issues each authorized user a unique public key certificate, （2） the one-way hash chain extends the certificate＇s lifetime, （3） the original media is encrypted by the session key and delivered to the communication group, and （4） the session key is periodically updated and distributed with the media. Finally, analyses and test results show that scheme provides a secure, scalable, reliable, and efficient access control solution for P2P live streaming systems.

A Loss-Tolerant Group Key Management Scheme with Revocation Capability for Wireless Sensor Network

A new group key management scheme against the unreliable wireless communication channel and unsafe environment was proposed for wireless sensor network(WSN).In the proposed scheme,broadcast polynomial, generated over finite field F_q based on the secret sharing,was employed to revoke compromised sensor nodes.In order to tolerate key-update message loss,group session keys were generated as one-way hash chain sequence and distributed in advance.The analysis showes that the scheme has better performance in terms of the computation and communication overhead.

An Authenticated Group Key Distribution Scheme for Wireless Sensor Networks

In wireless sensor networks （WSNs）, group key distribution is the core of secure communications since sensor nodes usually form groups and cooperate with each other in sensing data collection and in-network processing. In this paper, we present a scalable authenticated scheme for group key distribution based on a combinatorial exclusion basis system （EBS） for efficiency and one-way hash chains for authentication. The proposed scheme guarantees a lightweight authenticated group key updating procedure and is efficient in terms of storage, communication and computation overheads.