Trust-Aware Service Chain Embedding

Network function virtualization (NFV) decouples network functions (NFs) from dedicated hardware, leading to significant cost reduction in network service provisioning. With NFV, a network service is represented by a series of inter-connected virtual network functions (VNFs), forming a service function chain (SFC). The problem of placing the VNFs on the NFV infrastructure (NFVI) and establishing the routing paths between them, according to the service chain template, is termed as SFC embedding. The objectives and constraints for the optimization problem formulation of SFC embedding may vary depending on the corresponding network service. We introduce the notion of trustworthiness as a measure of security in SFC embedding and thus network service deployment. We formulate the resulting trust-aware SFC embedding problem as a Mixed Integer Linear Program (MILP). We relax the integer constraints to reduce the time complexity of the MILP formulation, and obtain a Linear Program (LP). We investigate the trade-offs among the two formulations, seeking to strike a balance between results accuracy and time complexity.