Towards a reliable communication network for International Monitoring System

Building a secure and reliable network system especially for safety critical applications is an extremely challenging task even when the scale of the application or physical boundaries of the system are small and well-defined. The complex issues in network communications, security and data quality apart from the high reliability requirements pose difficult scientific problems one has to tackle with. In the context of the international monitoring system, these challenges become much more daunting due to heterogeneous network topologies, mixing of private networks and internet as well as the enormity of geographical coverage. This paper attempts to provide an overview of the various approaches followed internationally in dealing with reliable network communications. One of methods highlighted in this paper for a secure communication for the International Monitoring System is the usage of Virtual Private Networks (VPN) in the identified sensor locations to communicate data to desired local access server locations through unsecured public networks. This setup could be for nearby local stations within a specified radius. The data is routed through a tunnel to local servers in the VPN using protocols such as IPSEC, PPTP etc. Multi-homed network that provides redundant links are cost effective and are proposed as means to ensure high reliability and end-to-end availability between the VPN servers to the centralized system located at Vienna. This paper also compares various communication technologies and dependability strategies available and recommends suitable combinations that overcomes the challenges such as malicious attacks, various failure modes, dynamic changing of the routing table to address dead links etc., to preserve data integrity and provide highly reliable information to the end users.