Virtualising control centres: can cloud computing deliver increased resilience?

Author: Matthew Slade
Day: Aspect Day Two
Session: Innovation and Future Development (2)

The use of 'cloud' computing has become increasingly prevalent over the last 10 years; 95% of organisations now use some form of 'cloud' based computing. Virtualisation is one service commonly grouped under the term 'cloud' and refers to the logical splitting of hardware resources to abstractly run multiple 'Virtual Machines'. This process is commonly used to provide desktops for employees and to host servers for data storage or running of applications. Migrating to virtual environments provides a range of benefits, including scalability, hardware cost savings and maintenance efficiency.More recently Industrial Control Systems (ICS) have started harnessing the benefits of virtualisation by hosting their supervisory, planning and management layer applications in virtual environments. It is estimated that 30% of current ICS systems contain some form of virtualisation and this is expected to increase significantly over the coming years. Within the railway industry we are yet to commonly adopt virtualisation, this is partly due to our focus on integrity and availability in comparison to most industrial control systems and everyday business.This paper introduces virtualisation and proposes an architecture for Railway Signalling Control Systems utilising virtual machines to host the train control and traffic management layers of our systems. The objective of this paper is to stimulate discussion regarding the adoption of such a change, highlighting the benefits to the resilience of our railways and the challenges such a change would introduce. The topics to be discussed include:
  • System Availability – Use of virtualisation facilities such as resource pooling, encapsulation, live transfer of guest environments and geographic diversity, enhancing the fault tolerance and availability.
  • Maintainability – Centralisation of software and hardware to remote locations allowing easier access for engineers.
  • Obsolescence Management – Migration of some functions into software that would otherwise be provided by Commercial Off The Shelf (COTS) equipment (e.g. network switches and physical servers). This will reduce the overhead for recertification hardware as COTS suppliers update firmware and components.
  • Backup Control Facilities - The ability to provide low cost back up control facilities using virtualised servers and workstations.
  • Testing and Commissioning – Creation of virtual test systems to verify correct operation of software patches and updates prior to commissioning on live systems. The tested updates can be installed and configured prior to being seamlessly transferred into service.
  • Work Force Competence - Consideration of the changes the industry will need to make in order to upskill the workforce to support the change. - Commercial Arrangements – The challenge of developing an appropriate commercial and practical framework for the supply of virtual environments by internal or third party suppliers.
  • Cybersecurity – Inevitably virtualisation increases the potential attack surface of our systems. However, this change also provides advantages over the status quo. The paper summarises the pros and cons and looks at the next steps required to address the challenges related to cybersecurity.Virtualisation is benefiting other industry sectors; the Signalling and Telecommunications community must strive to address the challenges of its introduction in our environment, in order to realise the benefits for our clients.