Review Article

Software-Defined Networks for Optical Networks Using Flexible Orchestration: Advances, Challenges, and Opportunities

Table 12

Summary of SDN orchestration solutions and challenges.

ReferencePolicy/algorithm/strategyProblem addressedImprovement/achievementWeakness/limitation

[63] (2020)Software-defined network orchestratorChallenges and demands presented by OpenFlow. Controlled software-defined optical networks (SDONs) and the issue of matching between services and SDON.Improved the performance of several services in SDON
[64] (2021)Software-defined network orchestratorNetwork performance based on blocking probability, jitter, delay metrics, and assignment of resource problems and challenges inside the controller.Improved network resource allocation path. Improved blocking probability. Identifies the path that best suits each flow.Limited resource utilisation. Needs further improvement with machine learning algorithms. The proposed algorithm is not dynamic and flexible.
[112] (2020)Network service orchestrationCompare several single and multidomain attempts with each architecture’s advantages and disadvantagesTo contribute to an overall awareness of common ideas and methods to NSO practiceOrchestration mechanisms are not massively scalable and difficult to integrate with external components. One or more orchestrators might be involved, open and flexible enough to deal with future applications.
[55] (2020)Network service orchestrationProve best performed MANO frameworks based on some defined KPIs and metricsBased on findings proposed real applications deployed in production environments using more powerful NFVIs that support different virtualisation technologies (e.g., Kubernetes)No real-time application. OSM proved mature and robust and Cloudify proved appropriate for deployments that have no strict requirements such as runtime, SLA contracts, and network slicing, while SONATA provides a complete tool chain for automated NS management in the dynamic 5G context era.
[55] (2019)Software-defined network orchestrator/NFVOFor balancing of network load for easier distribution of resourcesImprovement in the “utilisation of bandwidth” and the overall throughput reducing the delaysQuality factor, signal-to-noise ratio, bit error rate, and overall performance are limited to 45 km
[131] (2019)Software-defined network orchestratorTo manage the throughput and bandwidth efficientlyImproved throughput of the network and well-met traffic standardsMore complex and cost ineffective since multiple SDN controllers are to be used. High power and energy usage.
[132] (2018)Software-defined network orchestrator and Bayesian classifierLess service consciousness when operating along with an OpenFlow protocol and less efficiency in bandwidth scheduling. These service areas in SDON need improvement.This study proposes the use of the platform “Bayesian classifier-based service-aware (BC-SA).” The BC-SA system has been implemented using the Bayes network paradigm for multiple services. This BC-SA technique was used by the SDON system to carry out more efficient planning of resources.High latency and unreliable approach