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Self-organizing networks could be next-gen OSS model

The concept of self-organizing networks emerging from LTE and IMS technology may offer service providers a new telecom OSS model for broad service operations management that automates processes and enables lower operations costs for high-volume, low-cost services.

From the editor: The self-organizing network (SON) concept coming out of emerging 4G LTE networks could provide the model for next-generation operations and business support systems (OSS/BSS). SON systems could help telecom carriers reduce operations expense by automating the manual steps needed to operate their networks and services efficiently in increasingly high-volume, low-cost services.

For the last decade, standards groups, vendors and service providers have grappled with the question of how to streamline operations to counter the rising costs of supporting rich new services to larger and larger market segments. For the most part, the presumption has been that operations and business support systems (OSS/BSS) would be altered in some way to be more "service-efficient." Today, more and more providers are looking hard at an alternative model based on expanding an LTE notion: the "self-organizing network."

By focusing operations on infrastructure, self-organizing network principles control the largest cost component for service providers -- operations.

Tom Nolle
CIMI Corp.

OSS/BSS systems are designed to make the operations processes associated with service lifecycles more efficient and to lower the operating expense associated with them. Over time, process automation enhancements and new structural models, like the TMF's enhanced Telecommunications Operations Map (eTOM), have transformed OSS/BSS into a service-driven automated process set.

But even a brief examination of the new model shows that "service" and "contract" are almost synonymous, and a look at the trends in modern-day consumer Internet service shows why that's not necessarily a good thing.

LTE, IMS qualities contribute to new SON systems concept

Complex operations and billing processes are more easily justified for services with long lives and high prices. To get around this, high-volume, low-cost services tend to be managed in aggregate. 

In fact, the service that earns the most provider revenue worldwide -- voice -- is never contracted and assured on a per-call basis. To the extent that future high-volume, low-cost services will be short-lived, they'll have to be managed in aggregate, as well. The question is how, and the answer may come from a fusion of two technologies emerging out of LTE.

  • At the radio network level, the hottest trend in LTE is the concept of a self-organizing network where radio cells are dropped in and automatically structure themselves relative to their neighboring cells. This reduces the operations planning and deployment cost significantly.
  • LTE is also likely to promote the use of IP Multimedia Subsystem (IMS), since VoIP calling is the "native" voice language of LTE radio networks. IMS is arguably based on aggregate management and self-organizing principles, as well. As a result, self-organizing networks could become the management framework for future services.

Self-organizing networks, to be effective, would have to offer what's been called "semi-automatic" service management, from creation through termination, and extend through all of the protocol layers involved in the service. A practical approach would involve the following:

1. State-of-the-art self-organizing behavior at the LTE layer for wireless services. Normal base stations and femtocells could be added to the network and removed from service without explicit provisioning.

2. An extended metro network with IP (or IP/Ethernet) infrastructure. The metro network would be extended widely so paths to wireless base stations or metro wireline points of presence (POPs) could use "elastic" and dynamic capacity allocation rather than fixed circuit-like paths.

3. Multiple classes of service through the service geography. Each class of service would be based on provisioned and capacity-managed routes that are treated by the OSS/BSS systems as "services" but are allocated dynamically through higher-layer service signaling at the control plane.

The point on "class-of-service" versus "service" lifecycle management has already been raised in standards bodies, particularly in relation to IMS and the ITU NGN architecture. Both presume that the "control layer" of the network, where service requests (including calls) are made, would interact with the data-handling part of the network through a resource and access control function (RACF). In the data network, traffic would be managed by service class.

This model is similar to that of "directory-enabled networking" (DEN), which emerged more than a decade ago as an identity- or application-based mechanism for controlling network behavior without explicit provisioning. Google, Cisco and others have activities or patents in this space, which suggests that many key industry players are already seeing the trend and the opportunity.

The application of self-organizing principles to service management would have significant impact on operations for the short-lived, high-volume services that the concept would target. For example, the process of provisioning would be largely one of policy management, since the only requirement would be to certify the customer's right to access a given service.

In wireless IMS services, this is a part of the Home Subscriber Server (HSS) function. Most lifecycle management would be focused only on ensuring that the resources assigned to each class of service were performing to meet the service-level agreement (SLA) of that class.

Billing would go it alone in a self-organized networking world

Another implication of self-organizing principles is a separation of billing from other aspects of service management. The notion that all services were billed and managed from a single process has resulted in considerable consolidation and integration between billing and provisioning. But with "services" being handled purely at the control layer (what IMS calls the "service plane"), billing is likely to be a response to a service request made through signaling and not through management interfaces. This means independent billing products may gain in popularity.

Acceptance of self-organizing networks might also affect the design of OSS/BSS systems and the activities working on OSS/BSS standards. The question of how management processes would scale to the volume of consumer service demands would be moot, and most management practices would not be applied on a per-consumer basis.

At one level, this simplifies the evolution of the OSS/BSS model by eliminating a major scalability concern; but at another level, it may reduce the relevance of the model. There is no contract or order in a class-of-service-based world and, in fact, the older ITU model that viewed service management as a layer built on network management may be more relevant to future practices.

Summarizing the self-organizing network opportunity

Expanding the notion of self-organizing networks from the pure LTE radio domain to the broader service management domain seems inevitable, simply because broadband access and the Internet are creating a more "incident-driven" model of services to replace the contract-driven model. Complex operations processes can quickly end up costing more than the services they support as service requests increase in number and the price of an individual service declines. By focusing operations on infrastructure, self-organizing network principles control the largest cost component for service providers -- operations.

About the author: Tom Nolle is president of CIMI Corporation, a strategic consulting firm specializing in telecommunications and data communications since 1982. He is a member of the IEEE, ACM, TMF and IPsphere Forum, and the publisher of Netwatcher, a journal in advanced telecommunications strategy issues. Check out his networking blog Uncommon Wisdom.

This was last published in July 2009

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