Candidate Selection Algorithms for Hybrid IP/SDN Networks With Multi-Link Failures

A longstanding problem in the context of computer networks is the issue of recovery from link failures. A promising solution to safeguard all single link failures (SLF) is through partial up gradation of certain IP routers (Internet Protocol(IP)) to Software Defined Networking (SDN) switches using CSA (Candidate Selection Algorithms). The resultant network comprises a combination of IP routers and SDN switches, forming a hybrid IP/SDN network. Most of the existing approaches primarily address SLFs, yet real-world scenarios may involve multiple link failures (MLF). Hence, it's crucial to investigate CSA for Hybrid IP/SDN with MLF. In this paper, we first introduce four CSA strategies tailored for hybrid IP/SDN networks with MLF. Subsequently, we present a CSA designed to accommodate network scaling or expansion. We emphasize the advantage of CSAs based on non-shortest path approach. Additionally, we propose a budget constraint-based CSA to aid in selecting suitable candidate switches within a specified budget. We evaluate the performance of hybrid IP/SDN networks employing the proposed CSAs, considering average repair path length (AMLU) and average maximum link utilization (AMLU) in the post-recovery network across diverse real-world network topologies. It will be shown that the hybrid IP/SDN with proposed CSA for MLFs will reduce the ARPL by 31.37%, 22.15%, and 18.64%, respectively, for NSF, Attmpls, and Abilene networks.