Research On The Key Technologies For Security Of Publish/Subscribe Systems

The increasing demand for content-centric applications has motivated researchers to rethink and redesign the way information is stored and delivered on the Internet. Increasingly, network traffic consists of content dissemination to multiple recipients. However, the host-centric architecture of the Internet was designed for point-to-point communication between two fixed endpoints. As a result, there is a mismatch between the current Internet architecture and current data or content-centric applications, where users demand data, regardless of the source of the information, which in many cases is unknown to them. Content-based networking has been proposed to address such demands with the advantage of increased efficiency, network load reduction, low latency, and energy efficiency. The publish/subscribe (pub/sub) communication paradigm is the most complex and mature example of such a network. This dissertation mainly focuses on the key technologies for security of publish/subscribe system, especially to achieve an efficient, secure information distribution and management scheme to ensure the integrity, confidentiality and availability of information. The main innovations are listed as follows:(1) To guarantee information security of publish/subscribe system in a non-full trusted network environment, an encryption algorithm based on redundant attributes is proposed for the multi-domain publish/subscribe system model. The algorithm uses the redundant attributes of events to constitute a vector space model, and encrypts redundant attributes the same as general attributes. The redundant attributes of events appear in different combinations as the pre-established rule in the routing during events transmission. So once we found the information is leaked to unauthorized clients, we can discover links with wire-sniffing by the combination of redundant attributes in the information and revoke related authorized certificates. In this way we don’t increase the overhead of the matching progress and the subscribing progress. Therefore, our design contributes to improving the security of the Publish/Subscribe systems when wire-sniffing can not be neglected. The simulation results show that proposed approach can effectively improve the safety performance of the system without full trusted broker-to-broker connections support.(2) In order to achieve three objectives of access control in publish subscribe system:availability, integrity and confidentiality. An access control mechanism based on encrypted advertisement messages is proposed for improving the situation of encrypting only the content of events and leaving the access control policies unencrypted. The approach not only controls the security of information dissemination, but also retains the advantages of publish subscribe communications, such as decoupling of clients and overall system scalability. Subscriptions need to be joined with advertisements in the network so that an event dissemination tree for publications is set up. On this basis, we add access policies including sensitive data to the advertisement messages. Then we encrypt advertisement messages the same as publication messages. The security of access control policy is realized by the matching process of subscription messages and advertisement messages. In this way, we can achieve both information encryption and content-based routing, and will not increase overhead of publishing process. The simulation results show that proposed approach can support fine-grained control of information and efficiently improve security performance of access control policy but only increase a little overhead of messages.(3) In the Content-Based publish subscribe system, with thousands of subscriptions, it is not feasible to apply a centralized mechanism to handle the security requirements. Moreover, the number of Subscribers interested at a particular service/instance may vary with time. Therefore, it is impossible to set up static security groups. To solve this problem, we propose a hybrid mode key management mechanism to manage encryption key of events, which uses decentralized mechanisms for efficient grouping and provides including registration, key generation and dynamic membership management. The simulation results show that proposed model can effectively reduce the overhead of rekeying and key storing in the publish/subscribe system compared with other methods.