By Dr. Marcelo Blatt

Many service providers and other players in the telecommunications industry are talking about IMS (IP Multimedia Subsystem) as if its success is already a foregone conclusion.  It certainly may be the case.  The IMS network architecture – if properly implemented – offers an answer to the demands of both consumers and providers.  As our communications technology progresses, consumers have come to demand an increasingly varied and individualized set of services and content.  They want to be able to access these services from any network in any location, and with the same QoS.  In fact, QoS is becoming a particularly important requirement, as many of the new multimedia services are more sensitive to network performance and service degradation.

In addition to the consumers, service providers as well have a set of demands for which the current network structure and business model is insufficient.  First and foremost, providers need a solution that will enable them to answer the consumer demands mentioned above.  Providers are seeking to offer these services over a converged IP network, while moving beyond the current internet business model of a commoditized "bit pipe," and to provide real added value as a way of developing their end of the business. 

In theory, IMS network architecture takes all of these demands into account.  IMS will answer both consumer and provider demands to offer bundled multimedia services and rapid low-cost deployment of new services.  At its core, IMS is based on a converged IP network, answering the demand for flexibility and cost control.  IMS will provide consumers with the high-quality nomadic service they demand because it includes infrastructure with the potential to provide the same QoS while allowing consumers to gain access from any location or network.  More importantly for service providers, IMS provides a framework in which they can move beyond the restrictive flat rating "bit pipe" business model and offer added value for increased profitability.  With the benefits it has to offer on both ends of the market, IMS has the potential to become the widely accepted network standard in the near future.

However, providers need to be careful about the way they pursue the implementation of IMS.  By incorrectly prioritizing the initial stages of rollout and moving forward without the proper OSS features, IMS profitability and market success may be jeopardized, or at the very least seriously set back.  Many providers are planning to begin by devoting the bulk of their resources toward the billing and service provision mechanisms in order to quickly establish market share and the new business model, and then address Service Assurance and QoS in later stages.  However, without consistently providing a high level of QoS and end-user experience, IMS will not achieve sustainable success.  IMS standards do provide the infrastructure for end-to-end QoS, but this will just be wasted potential if it is neglected in the initial stages of rollout.  In order to achieve the potential for IMS and ensure its adoption, service providers will need to include Service Assurance in their rollout strategy.

Service Assurance vendors will need to provide a solution with more advanced capabilities to help operators meet the challenges of ensuring QoS in an IMS environment.  These challenges arise from both the IMS architecture itself, as well as the market conditions surrounding it.   Complex traffic patterns have become a source for service impact that was not present in traditional networks, where the leading sources for service deterioration have been network failures such as element malfunctions