In the modern world, computers have penetrated ever deeply into our society, and in turn, society is becoming more dependent on computer systems. This increased reliance on computer systems brings the requirement for increased availability and reliability, assurance and dependability to the fore. However, the complexity of today's systems, in particular distributed systems, makes these requirements difficult to achieve or even assess. In order to increase reliability of those systems and to deal with the availability issues arising from contemporary partitioned (i.e. degraded) networks, their...