Increasing need for business agility and superior customer experience are driving the demand for orchestrators. Often automation and orchestration are used in combined, but those two functions are quite different though interrelated. Let’s look at the functionalities of orchestration in order to get a better understanding.
Orchestrators sit on top of controllers, managers and network nodes. Orchestrator has the holistic view of each system and have the capability to instruct them. This is similar to how an orchestrator handles musicians in a symphony or how a project manager handles multiple resources and tasks in a project. Orchestrator does not get involves in the task itself but overlooks and manage tasks. In contrary automation represents the task.
Orchestration looks at ‘service fulfillment’ which can entail multiple automation tasks. Or in other words, orchestrators look at things not only from a technology point of view but also from a business perspective and instructs respective systems to perform tasks in order to cater the need. When it comes to service fulfillment orchestrators define services catalogs, their specifications based on which it fulfills a service and billing details. In order to do this, orchestrators must integrate with multiple other systems such as OSS/BSS, Billing, CRM in a business environment. Since orchestration looks at end to end service fulfillment it also consists of default functions such as controlling, assurance and billing.
Under the broad category of ‘service fulfillment’ there are multiple types of network orchestration that could take place. For instance, network ‘services’ orchestration is one type where provisioning of VPN, internet links takes place. These are typically the services that runs on a network. Another type of orchestration could involve ‘resource’ orchestration which means orchestration of resources such as compute, storage, IP address pools. Network ‘topology’ orchestration is another type where it considers impacts to network topology based on changes made to a network through automated tasks.
Let’s look at another aspect of an orchestrator. Examples and use-cases spoken above largely discuss the usage of orchestration in relation to service provisioning. In addition to service provisioning, network orchestration also looks at other aspects such as ‘scale up’ ‘scale down’ of resources, ‘service chaining’ and ‘zero touch provisioning’ of network nodes either in VNF or CNF form.
With the trend for ‘softwarization’ of networks continue, network nodes will take either VNF or CNF form. This gives enormous benefits for a business as network nodes can now be elastically adjusted to cater workloads on demand. Thus, creating the need for an orchestrator to centrally manage automated scaling and mobility of nodes. In addition to scale and mobility, there also arises the need to provision and deprovision nodes. This is again a function of the orchestrator where it can automatically provision or deprovision nodes.
There are multiple frameworks that describes the functionality of a network orchestrator. And one such framework is MEF 55 specification which describes the LSO -Life Cycle Service Orchestration framework that discusses the orchestrator framework in detailed especially in a SDN environment.