Securing a Open Hypermedia System (OHS) Using MQSeries Everyplace (MQe) David C. De Roure, Kenneth K. K. Tso, Department of Electronics & Computer Science, University of Southampton, Highfield, Southampton, SO17 1BJ, UK {dder, kt00r}@ecs.soton.ac.uk Howard Lambert IBM United Kingdom Ltd, Hursley Park, Winchester SO21 2JN howard_lambert@uk.ibm.com Abstract The Open Hypermedia Systems Working Group (OHSWG) has spent years working on Open Hypermedia Protocol and Open Hypermedia Systems. However, relatively less consideration is given to security, for instance, a contextual link server known as “Auld Leaky” was built with no security features at all. MQSeries Everyplace is designed with many security features necessary for building a secure open hypermedia system. “Auld Leaky” was chosen to integrate with MQSeries Everyplace making use of the security features. MQSeries Everyplace enables a secure client- server link service to be extended to a secure peer-to-peer distributed link service. Introduction In recent years, the Open Hypermedia Systems Working Group (OHSWG) has been continuously developing [3] and defining [8] the Open Hypermedia Protocol (OHP) [4] in an attempt to achieve interoperability between Open Hypermedia [1] [2] [5] [9] 10] Systems. Within the Intelligent Agents Multimedia group at Southampton, the Fundamental Open Hypermedia Model (FOHM) [7] based on the OHP model was developed. In addition, a contextual link server known as “Auld Leaky” [6] is constructed around FOHM. Since “Auld Leaky” is a link server designed to be simple, lightweight but without considerations of security, it becomes susceptible to attacks over the Internet, in particular, when transmitting data in plaintext over an open network (e.g. via HTTP). MQSeries Everyplace (trademark of International Business Machines Corporation) (MQe) provides sophisticated security capabilities (including authentication and encryption) to applications running outside the protection of firewall. By integrating with MQSeries Everyplace and making use of its security capabilities, “Auld Leaky” can be enhanced from a link server with no security to a link server with full security. This paper describes firstly the security weaknesses of “Auld Leaky”, and secondly, an overview of MQSeries Everyplace security features. Thirdly, one possible way of changing “Auld Leaky” into a secure Open Hypermedia System using the security features provided in MQSeries Everyplace is described. Finally, the potential of extending a secure client-server link service to a secure peer-to-peer distributed link service is also discussed. Security weaknesses in “Auld Leaky” The potential security threats or weaknesses of “Auld Leaky” are: (as security was not a prime concern when designing “Auld Leaky”, several security weaknesses exist, which make it vulnerable to malicious users). First of all, transmitting data in plaintext over an open network via HTTP means that there is no confidentiality of the data. In addition, there is no authentication process and hence no control of access to “Auld Leaky” once its URL and port number is known. As a result, anyone could