Modern Network Technologies and Dependability

This paper discusses the dependability issues of modern network technologies. These include cloud computing, software-defined networking, Internet of things, the 5th generation mobile networks. Particular attention is paid to the selection of appropriate dependability measures, target values for them, and methods for dependability assurance. The consideration is based on standards and other documents of international organizations (ITU, IEC, ISO, 3GPP). Inconsistencies and inaccuracies in some of these documents regarding dependability are identified. The necessity of using end-to-end availability in service level agreements for cloud computing is rationalized. The complexity of estimating end-to-end network availability for software-defined networks is justified, and the lower bound for it is derived. For Internet of things systems, the use of the effectiveness retention ratio as a dependability measure is suggested.