Recovery Model for Survivable System through Resource Reconfiguration

A survivable system is able to fulfil its mission in a timely manner, in the presence of attacks, failures, or accidents. It has been realized that it is not always possible to anticipate every type of attack or failure or accident in a system, and to predict and protect against those threats. Consequently, recovering back from any damage caused by threats becomes an important attention to be taken into account. This research proposed another recovery model to enhance system survivability. The model focuses on how to preserve the system and resume its critical service while incident occurs by reconfiguring the damaged critical service resources based on available resources without affecting the stability and functioning of the system. There are three critical requisite conditions in this recovery model: the number of pre-empted non-critical service resources, the response time of resource allocation, and the cost of reconfiguration, which are used in some scenarios to find and re-allocate the available resource for the reconfiguration. A brief specifications using Z language are also explored as a preliminary proof before the implementation .. To validate the viability of the approach, two instance cases studies of real-time system, delivery units of post office and computer system of a company, are provided in ensuring the durative running of critical service. The adoption of fault-tolerance and survivability using redundancy re-allocation in this recovery model is discussed from a new perspective. Compared to the closest work done by other researchers, it is shown that the model can solve not only single fault and can reconfigure the damage resource with minimum disruption to other services

A SURVIVABLE DISTRIBUTED DATABASE AGAINST BYZANTINE FAILURE

Distributed Database Systems have been very useful technologies in making a wide range of information available to users across the World. However, there are now growing security concerns, arising from the use of distributed systems, particularly the ones attached to critical systems. More than ever before, data in distributed databases are more susceptible to attacks, failures or accidents owing to advanced knowledge explosions in network and database technologies. The imperfection of the existing security mechanisms coupled with the heightened and growing concerns for intrusion, attack, compromise or even failure owing to Byzantine failure are also contributing factors. The importance of  survivable distributed databases in the face of byzantine failure, to other emerging technologies is the motivation for this research. Furthermore, It has been observed that most of the existing works on distributed database only dwelled on maintaining data integrity and availability in the face of attack. There exist few on availability or survibability of distributed databases owing to internal factors such as internal sabotage or storage defects. In this paper, an architecture for entrenching survivability of Distributed Databases occasioned by Byzantine failures is proposed. The proposed architecture concept is based on re-creating data on failing database server based on a set  threshold value.The proposed architecture is tested and found to be capable of improving probability of survivability in distributed database where it is implemented to  99.6%  from 99.2%.

Recovery Model for Survivable System through Resource Reconfiguration

A survivable system is able to fulfil its mission in a timely manner, in the presence of attacks, failures, or accidents. It has been realized that it is not always possible to anticipate every type of attack or failure or accident in a system, and to predict and protect against those threats. Consequently, recovering back from any damage caused by threats becomes an important attention to be taken into account. This research proposed another recovery model to enhance system survivability. The model focuses on how to preserve the system and resume its critical service while incident occurs by reconfiguring the damaged critical service resources based on available resources without affecting the stability and functioning of the system. There are three critical requisite conditions in this recovery model: the number of pre-empted non-critical service resources, the response time of resource allocation, and the cost of reconfiguration, which are used in some scenarios to find and re-allocate the available resource for the reconfiguration. A brief specifications using Z language are also explored as a preliminary proof before the implementation .. To validate the viability of the approach, two instance cases studies of real-time system, delivery units of post office and computer system of a company, are provided in ensuring the durative running of critical service. The adoption of fault-tolerance and survivability using redundancy re-allocation in this recovery model is discussed from a new perspective. Compared to the closest work done by other researchers, it is shown that the model can solve not only single fault and can reconfigure the damage resource with minimum disruption to other services

Survivor: An Approach for Adding Dependability to Legacy Workflow Systems

Although they often provide critical services, most workflow systems are not dependable. There has been much literature on dependable/survivable distributed systems; most is concerned with developing new architectures, not adapting pre-existing ones. Additionally, the literature is focused on hardening, security-based defense, as opposed to recovery. For deployed systems, it is often infeasible to completely replace existing infrastructures; what is more pragmatic are ways in which existing distributed systems can be adapted to offer better dependability. In this paper, we outline a general architecture that can easily be retrofitted to legacy workflow systems in order to improve dependability and fault tolerance. We do this by monitoring enactment and replicating partial workflow states as tools for detection, analysis and recovery. We discuss some policies that can guide these mechanisms. Finally, we describe and evaluate our implementation, Survivor, which modified an existing workflow system provided by the Naval Research Lab

Computer Immunodeficiency: Analogy between Computer Security and HIV

Current security systems are designed to prevent foreseeable attacks. Those security systems do not prevent effectively the more emergent types of attacks, like a botnet, whose presence and behavior is difficult to predict. In order to predominate those types of attacks, we advocate an adaptive security approach based on the animal immune system. But since those sophisticated attacks can also be directed at the security systems themselves, leading to computer immunodeficiency, like HIV, in this paper we propose a protocol that protects the immune system itself. This approach discriminates between attacks on the security systems, which are part of the computer immune system, and attacks on other vital computer systems in an information infrastructure

Survivable mesh-network design & optimization to support multiple QoP service classes

Every second, vast amounts of data are transferred over communication systems around the world, and as a result, the demands on optical infrastructures are extending beyond the traditional, ring-based architecture. The range of content and services available from the Internet is increasing, and network operations are constantly under pressure to expand their optical networks in order to keep pace with the ever increasing demand for higher speed and more reliable links