  Networks can now process data as well as transporting it; it follows that
they can support multiple services, each requiring different key performance
indicators (KPIs). Because of the former, it is critical to efficiently
allocate network and computing resources to provide the required services, and,
because of the latter, such decisions must jointly consider all KPIs targeted
by a service. Accounting for newly introduced KPIs (e.g., availability and
reliability) requires tailored models and solution strategies, and has been
conspicuously neglected by existing works, which are instead built around
traditional metrics like throughput and latency. We fill this gap by presenting
a novel methodology and resource allocation scheme, named OKpi, which enables
high-quality selection of radio points of access as well as VNF (Virtual
Network Function) placement and data routing, with polynomial computational
complexity. OKpi accounts for all relevant KPIs required by each service, and
for any available resource from the fog to the cloud. We prove several
important properties of OKpi and evaluate its performance in two real-world
scenarios, finding it to closely match the optimum.
