Optimal VNF Chains Management for Proactive Caching

Notwithstanding the significant attention that Network
Function Virtualization (NFV) architectures received over
the last few years little attention has been placed in cases
where proactive caching is considered within a service chain.
Caching algorithms have been developed independently from
virtual network function (VNF) chaining schemes and as we
explain in detail in this paper such operation might lead to suboptimal
overall network and service performance. Since caching
of popular content is envisioned to be one of the key adopted
technologies in emerging 5G networks to increase network
efficiency and overall end user perceived quality of service we
explicitly consider the interplay and subsequent optimization of
caching based VNF service chains. To this end, a mathematical
programming framework is proposed tailored to VNF caching
chains and in addition detail a scale-free heuristic algorithm to
provide competitive solutions for large network instances since
the problem itself can be seen as a variant of the classical NPhard
Uncapacitated Facility Location (UFL) problem. A wide set
of numerical investigations are presented for characterizing the
attainable system performance of the proposed schemes.