Over a seven year period from 1982 to 1989,3337 conduits were created in 3137 patients with end stage renal disease (ESRD) as access for chronic dialysis. These included 2690 side-to-side arteriovenous fistulae (A VF), 168 end-to-side A VFs, 10 autogenous vein grafts, 51 homogenous frozen vein grafts, 109 polytetrafluoroethylene (PTFE) grafts, 209 emergency external arteriovenous shunts, t...

This paper emphasizes that instead of long-term availability and reliability, the short-term session durability analysis will greatly impact the design of the real large-scale Peer-to-Peer storage system. In this paper, we use a Markov chain to model the session durability, and then derive the session durability probability distribution. Subsequently, we show the difference between our analysis...

One of the most important problems of reliability analysis is to estimate the mean lifetime of the item under study. In technical applications this parameter is also called the mean time to failure (MTTF) and is often included in the specification of a product. For example, producers are interested whether this time is sufficiently large, as a large MTTF allows them to extend a warranty time. C...

Exercise 1 Let us consider a system composed of n different components denoted 1, 2 ……n, with m identical replicas of each component. Two redundancy strategies are studied:-GR, in which redundancy is applied globally at the system level: the architecture is composed of m identical copies of the system that are organized according to a parallel structure.-LR, in which redundancy is applied local...

Increasing MTTF requires increasing reliability. In previous lectures we saw a variety of ways to do so: testing, static analysis, formal methods, etc. A highly reliable system is a highly available system. Reducing MTTR requires reducing the (mean) time it takes for the system to come back up once a failure has occurred. Once a failure occurs, we must detect it, diagnose it, and the recover th...