VNF Orchestration and Power-Disjoint Traffic Flow Routing for Optimal Communication Robustness in Smart Grid With Cyber-Physical Interdependence

Abstract

We explore the use of software-defined networking (SDN) technology in building a communication network for smart grid. With cyber-physical interdependence, such communication network may suffer from cross-network cascading failures. To prevent the failures, we perform virtual network function (VNF) orchestration jointly with power-disjoint routing. Our work is novel in proposing an efficient scheme to find power-disjoint routes at the same time of performing VNF orchestration. We formulate an optimization to maximize the ratio of power-disjoint route count to VNF orchestration cost. The optimization has a non-linear non-convex objective function. We propose a twolevel hierarchical solution approach. At higher level, the scheme converts the problem into a fractional maximum flow circulation, which can be solved using simplex method to find the maximum number of power-disjoint routes. Given a higher level solution, the lower level aims to minimize the VNF orchestration cost while satisfying VNF chaining and placement requirements. This lower level hierarchy uses the Dijkstra's algorithm in building a sequence of minimum spanning trees, each roots at the current VNF hosting node in a VNF chain. Extensive simulation results confirm that the proposed scheme can find the maximum number of power-disjoint routes and minimize the cost within a second, for a system with 120 communication nodes. The results show that the number of power-disjoint routes can be increased by increasing either the number of nodes or node degree, but only the node degree can keep the cost flat. Therefore, one should build a robust software-defined smart grid communication network by enhancing node connectivity.

Risk-Balanced Routing Strategy for Service Function Chains of Cyber-Physical Power System Considering Cross-Space Cascading Failure

“…Since the virtual functions that should be included in the formation of a particular network service have not been standardized. Therefore, a general expression is used in this paper to represent the SFC and its constituent VNFs [19]. M is the set of VNFs in the network, and m ∈ M represents VNF m .…”

“…(2), ( 11), ( 12), ( 13), ( 14), ( 15), ( 18) (19) where μ is a small value used to prioritize the robust optimization objective.…”

“…In the context of the power system, the authors in [18] propose the hybrid fault path recovery algorithm to solve the problem of communication link failures in wide area measurement systems leveraging the flexibility of SDN technology to quickly recover communication routes in response to individual communication link failures. In order to prevent the power communication network from failing due to grid-side failures, reference [19] proposes a strategy to find disjoint power supply routes for VNF orchestration which also helps in finding the most efficient way to route traffic through a network while minimizing the cost of managing the network's virtual functions.…”

Communication network robust routing optimization in an integrated energy cyber–physical system based on a random denial-of-service attack

“…In a communication network, each communication path typically exhibits varying communication performance and reliability. The task of selecting the optimal communication path for service information flow, based on specific objectives, is known as a routing optimization problem (Karamdel et al, 2022;Kong and Jiang, 2022;Li et al, 2022). This problem can be further divided into routing balance optimization (Hammoudeh and Newman, 2015;Cai et al, 2022) and communication performance optimization (Du et al, 2022), depending on the optimization goals.…”

Analysis on Secured Cryptography Models with Robust Authentication and Routing Models in Smart Grid

“…As all devices communicate data via the Internet, the Internet Protocol (IP) is one of the most vulnerable parts of integrating ICTs into SG. As a result of its recognised flaws, this protocol is subject to intrusions and data tampering [27]. Despite this, there are numerous security flaws that need to be patched up.…”