Online Joint Placement and Allocation of Virtual Network Functions With Heterogeneous Servers

Abstract

Network Function Virtualization (NFV) is a promising virtualization technology that has the potential to significantly reduce the expenses and improve the service agility. NFV makes it possible for Internet Service Providers (ISPs) to employ various Virtual Network Functions (VNFs) without installing new equipments. One of the most attractive approaches in NFV technology is a so-called Joint Placement and Allocation of Virtual Network Functions (JPA-VNF) which considers the balance between VNF investment with Quality of Services (QoS). We introduce a novel capability function to measure the potential of locating VNF instances for each server in the proposed OJPA-HS model. This model allows the servers in the network to be heterogeneous, at the same time combines and generalizes many classical JPA-VNF models. Despite its NP-hardness, we present a provable best-possible deterministic online algorithm based on dynamic programming (DP). To conquer the high complexity of DP, we propose two additional randomized heuristics, the Las Vegas (LV) and Monte Carlo (MC) randomized algorithms, which performs even as good as DP with much smaller complexity. Besides, MC is a promising heuristic in practice as it has the advantage to deal with big data environment. Extensive numerical experiments are constructed for the proposed algorithms in the paper.

An inertial Douglas–Rachford splitting algorithm for nonconvex and nonsmooth problems

“…To solve this problem, some researchers proposed various algorithms by reducing the computation complexity in wireless communication applications, which can improve the performances of Cell-free massive distributed antenna systems, recognition speeds, online allocation efficiency of virtualized network services with different categories of servers, and so on. [8][9][10] Moreover, abundant achievements in compressed sensing, [11][12][13] sparse approximation of signals 14 and image processing, 15,16 etc. also rely on numerical techniques and algorithms for nonconvex problems.…”