… , from an availability viewpoint, an IP Multimedia Subsystem (… Firstly, we model the availability
of cIMS by employing both … service satisfying a desired availability constraint, whose results …

… ; second, we perform an availability analysis devoted at identifying the optimal redundant …
availability requirements (5.26 minutes of downtime per year), along with a sensitivity analysis …

… It is the case of [6] where an availability analysis of a virtualized EPC is … an availability
analysis aimed at identifying the optimal redundant configuration satisfying the high availability …

… In this work we face an availability analysis of an IMS infrastructure deployed in a 5G
scenario where the typical network nodes of the IMS architecture are replaced by modern VNFs. …

… In this section we proceed further on the definition of importance of availability of quality for
a service, a significant notion used in this paper. Following, is the presentation of the model …

… In particular, we perform an availability analysis aimed at identifying the optimal configuration
… The steady-state availability analysis is performed by considering different system …

… CONCLUSIONS In this work we introduced a tool useful to manage the availability of service
chains, where the example of virtualized IP Multimedia Subsystem (vIMS) has been tackled. …

… • We face an availability analysis and evaluation of softIMS by exploiting the Stochastic
Reward Networks (SRN) technique to deal either with common mode failures (due to a nested …

… One application that we analyze with respect to the service availability concept model
presented above, is the presence service. Basically, the presence server collects information …

… , a joint analysis of availability and performance (aka performability) of IP Multimedia Subsystem,
… (OptChains+), we carry on a performability analysis: i) to evaluate and compare series/…