Better coordination of operations across IP & Optical layers with SDN
In many networks, the IP and Optical operations staff are split into two separate teams. Expertise is aggregated around the IP layer in traffic engineering and tunnel management, while in the optical layer the infrastructure is tuned to deliver reliable, efficient transport. There are many good reasons to establish this kind of specialization, but the principal serious downside is the potential for information to be “lost in translation” between the teams as they maintain, troubleshoot and re-engineer their assigned network layer(s).
In smaller installations, there may be a single operations team with responsibility across the network layers. With traditional tools, the situation arises that an operator is effectively on a “swivel chair” – pivoting between dissimilar and non-integrated tools that are at least in different windows and possibly different workstations.
In either case, this coordination gap, whether between teams or tools, can lead to slow operational processes, cost duplication and impaired services to end users.
This is all happening in a time of increasing network complexity and the growing requirements for rapid adaptability and 24/7/366 availability. What is needed is an operational model with the tools to enable efficient, seamless multilayer, cross-domain operations. Fortunately, new technologies are appearing to support the development of these tools.
Programmable interfaces are becoming widely available across components in all network layers, unlocking the capability for software defined networking (SDN). SDN enables visibility across the entire operating network bringing fine-grained analysis and control of the state and performance of all network resources. The extent of this visibility and the crucial, actionable data it brings enable optimal decision making and efficient, automated control of the network. These capabilities can be leveraged across all network lifecycle operations such as: configuration, maintenance, traffic engineering and service availability assurance.
SDN-based tools can bridge the gap
SDN-based tools, such as those provided by the Nokia Network Services Platform (NSP) bring broad and deep, data-driven analysis and drive rapid, effective actions across and throughout the entire network to deliver resilient, high availability services. Multi-layer and cross-domain operations can be streamlined, and the network run more efficiently using programmable interfaces and leveraging automation as appropriate.
Analysing the benefits
Appledore Research have investigated the benefits, for a typical mobile communications service provider in optimizing its IP/optical transport network operations using the NSP. This quantitative benefits analysis was carried out, using real world network data from the transport network, and has identified significant OPEX, CAPEX and revenue loss savings. While this analysis was carried out for a service provider, the efficiencies and operational enhancements that were identified are equally applicable to networks supporting industrial applications such as energy utilities and transportation , or in the public sector. The process and the results can be examined in the paper: Multi-layer and multi-domain management using the Nokia NSP: A benefits analysis for CSPs worldwide."
“Nokia NSP provides the foundation to improve revenue and lower costs in CSPs. In a typical mobile operator with approximately 6 Million subscribers, our analysis demonstrated OPEX savings of around $3.8 million USD per year and revenue loss savings of around $2.4 million USD per year.”
Francis Haysom, Partner and Principal Analyst, Appledore Research
Reviewing the use cases
The principal use cases can be broadly grouped into three categories: discovery, correlation and optimization.
The NSP can automatically and accurately discover topologies at all layers and gather cross-layer connect information to verify the network architecture is correct. Compared with error-prone manual techniques this can reduce the probability of service outages and enable simpler troubleshooting.
While path diversity is needed for IP links or for IP services, paths may not be fully diverse in the optical domain. Paths that seem diverse in the IP domain may actually take the same optical fiber, or, they may take separate fibers that are within the same cable or duct, for example, hence sharing risk. A failure could impact both primary & backup paths. The NSP performs real time diversity analysis and can establish diverse paths as necessary. This can help reduce the probability of service outages.
With a broad span of network visibility, the NSP can rapidly identify root causes of alarm conditions and coordinate resolution activities across teams. Operators can navigate bottom-up and top-down across network layers in holistically supervising network operation. This brings efficiencies to multi-layer network operations.
Planned changes in optical topology, such as those that occur during network maintenance and hitless optical reversion can be coordinated with IP traffic routing to minimize impacts on end user services bringing improved customer satisfaction.
Cross-domain coordinated protection can be intelligently and efficiently applied at the appropriate layer. Using a ‘floating’ backup port can bring considerable savings in the number of interfaces (router ports and transponders) required.
Automated connection management based on standard protocols and interworking with 3rd party domain controllers can be supported. This reduces the need for complex and expensive OSS systems with long integration intervals and manual, error-prone processes. This can allow faster service delivery and operational cost savings.
To learn more about IP/Optical coordination with the Nokia Network Services Platform visit our web page: https://www.nokia.com/networks/solutions/ipoptical-coordination/
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