CSE 322: Software Reliability Engineering Topics covered: Architecture-based reliability analysis

Introduction and motivation

Benefits of architecture-based analysis

Application architecture  Architecture:  Components:  Interactions:

Application architecture (contd..)  Sequential application:  Dynamic behavior:

Application architecture (contd..)  Types of applications:

Application architecture (contd..)  Models used:  Mapping of control-flow graph to models:

Application architecture (contd..)  Type of models:

DTMC analysis  Overview of DTMCs:  Absorbing:  Irreducible:

Analysis of absorbing DTMCs

Analysis of absorbing DTMCs (contd..)

Analysis of irreducible DTMCs

Example of architecture analysis Terminating application 10 modules 1 is the input, 10 is the exit module Architecture modeled by absorbing DTMC Probability that the control is transferred to module j, upon execution of module i

Example of architecture analysis (contd..) Intercomponent transition probabilities

Example of architecture analysis (contd..) Component Mean number of visits Variance of the number of visits Computed for component i

Example of architecture analysis (contd..) Non-terminating application 10 modules Architecture modeled by irreducible DTMC Reliability of each component known Probability that the control is transferred to module j, upon execution of module i

Example of architecture analysis (contd..) Intercomponent transition probabilities Addition of two transitions to absorbing DTMC to make it irreducible

Example of architecture-based analysis (contd..) Component Utilization of the component Computed for component i