Reliability models for systems with internal and external redundancy

Abstract

As the rapid development of computer-based systems and networks, more and more applications require non-stop, highly reliable services. To achieve high service availability and reliability, traditional redundancy inside the system may not be sufficient for these applications. External redundancy and recovery strategies are critical to meet the high availability requirements, reduce failure impact and improve survivability. New network infrastructure and protocols made these redundancy structures and recovery strategies feasible. This paper presents an integrated Markov reliability and availability model to estimate and compare the downtime of the different recovery strategies. The model provides quantitative evaluations of reliability for the different architecture options. This can be further combined with other performance and capacity analysis to support architecture design and other decision making.

End-to-End Reliability and Optimization of Intra and Inter-Domain IMS-based Communication Networks

“…For example, state-space methods such as Queuing Network Model (QNM) [9][10][11], Queuing Petri Nets (QPN) [12], and the Markov model [8,[13][14][15][16][17] were applied for performance and reliability evaluation of the IMS network. The QNM is normally applied to analyze the processing delay.…”

“…The Markov model can take into account some detailed working states and system parameters such as failover and recovery rates. Besides, redundancy effect can also be included into the model for an evaluation [8,[15][16][17].…”

“…Further, system reliability and availability with internal and external redundancy were evaluated through the Markov model. The system availability was shown to improve for all redundancy mechanisms [15]. Moreover, an end-to-end reliability and resilience properties of the IMS system were evaluated by using the Markov Rewards Model and Reliability Block Diagrams (RBD) [16].…”

“…On the other hand, high reliability would refer to high availability. Then, from the high availability concept and from (15) and (16), with initial redundancy or M = 2, and with similar failure rate assumption for comparison purpose, λ = 2.4897 × 10 −7 sec −1 , the minimum redundancy number to achieve different end-to-end reliability as relating to high availability concept can be calculated and given in Table 1.…”

Deriving Job Completion Reliability and Job Energy Consumption for a General MapReduce Infrastructure from Single-Job Perspective

“…Zhang et al [9] estimated the downtime and availability of a system employing an activestandby redundant mechanism for both of its internal and external systems. But this model focused on system availability, rather than job completion reliability.…”