Over the last 20 years, there has been much discussion about unified communication for subscribers of wireline and wireless communication solutions. The primary focus of these discussions has been around large-scale enterprise environments, specifically those focused on fixed mobile convergence and IP voice integration into the desktop environment. Subscribers are excited about unified communications based on their desire to find a better way to communicate and manage their daily lives.

 

In recent years, Communication Service Providers (CSPs) across most market segments have seen a dramatic decline in Average Revenue Per User (ARPU), a rise in subscriber acquisition costs, and an increase in subscriber turnover. To combat these challenging trends, Communication Service Providers are increasingly looking to offer new innovative services and repurpose existing services for new networks. “Time to Market,” if not “First to Market,” is a critical success factor for new services being rolled out. Not only is the challenge to be first to market, but today’s consumer expectations are that these new services will provide feature transparency across networks. Namely, all applications should be available with a consistent user experience across the multiple underlying networks — fixed, mobile, or IP, regardless of network access.

 

 

In a perfect world, the underlying network infrastructure would be static and insulated from rapid change. This would allow the application developers to be free to focus on innovating applications and the feature transparency challenge would not exist. However, the reality of how networks are built and evolve precludes this utopia. CSPs have deployed dozens of different standards for networking and signaling over the years. Data networks still consist of multiple protocols, such as ATM, frame relay, and IP, with many variations of each. With the introduction of mobile and VoIP services, the complexity increases with protocols, such as H.323, IS-41, MAP, and SIP.

 

As CSPs continue to deploy new network assets and technology at an increasingly rapid pace, achieving feature transparency becomes even more challenging. The benefit of creating a solution to ensure feature transparency will provide subscribers application feature parity across multiple networks, enable the service providers to consolidate their application platforms and fully enable them to leverage their network assets to offer converged applications.

 

As regulatory rules change across the globe and service providers aggressively pursue their infrastructure evolution, multi-network convergence is already underway. This ongoing network convergence creates havoc for the goal of providing feature transparency. Initially, network convergence meant that voice networks would converge with data networks to create a new type of network. Once that concept was well understood and implementations were just starting, further network convergence was introduced and expanded to merge the wireline and wireless networks. (Of course the definition of wireless and wireline networks became more complicated with competing technologies that include WiFi and WiMAX (News - Alert).) Today’s service providers are challenged to simultaneously converge wireline, wireless and IP networks and as a result, exciting “triple” or “quad play” converged services are just beginning to be offered to subscribers. As these new services are commencing, service providers are facing the challenge of how to offer these new converged services and ensure the subscriber experience is the same regardless of the access network type used to access the applications.

 

The classic example of failing to achieve feature transparency across multiple evolving networks is seen in the Message Waiting Indicator function of a voice message application or platform. The mechanism to manipulate a message waiting indicator is specific to each user’s network. Many wireless networks use IN based signaling, INAP, CAMEL, IS41 or WIN to indicate to the HLR that a message is waiting or that the messages has been cleared. Wireline networks use other methods such as SMDI signaling or specific ISDN or SS7 messages to indicate to a Class 5 switch that a message is waiting. Messaging platforms must be able to support all of these mechanisms to provide this functionality and ensure application feature transparency. As the underlying networks evolve and converge, applications must react to these changes, otherwise there becomes a breakdown in the subscriber experience.

 

To fully understand the difficulty in ensuring feature transparency across multiple and evolving networks, it is essential to realize how applications and services are deployed today. The complexity of introducing and managing a constant flow of new services is financially and operationally taxing on organizations accustomed to rolling out new services in a slow, methodical manner over one network. Historically, new services were provided by Telecom Equipment Manufacturers’ (TEMs) vendors, such as Alcatel-Lucent, Nortel, and Ericsson (News - Alert), therefore the timeline for service availability was dictated by the roadmap of that equipment platform vendor. CSPs also have experience deploying services provided by independent application and messaging vendors, such as Comverse (News - Alert), Unisys, and Intervoice. These vendors integrate their standalone solutions into the infrastructure (such as network layer, OSS, and billing) of the CSP (News - Alert) and create an independent “application stove pipe” for each service deployed. Application stove pipes create complexity, time-to-market challenges, and resource inefficiencies for the CSP, but ultimately they cause feature transparency challenges as the network grows.

 

To ensure seamless feature transparency as the network evolves, Service Providers face the ongoing prospect of either re-purposing general purpose network elements or “re-writing” and “re-connecting” each and every application. The first option and the most prevalent includes re-writing the applications to add appropriate signaling or call control directly into the application to ensure the application behavior remains the same regardless of access network. This requires the application developer to re-write the application to support the evolving network, or the service provider must purchase a new set of applications to support the new network. The second method to address the evolving network’s impact on applications is the use of costly general purpose equipment such as soft switches, signaling gateways and media gateways. This solution provides the necessary rich call control and signaling required to support feature transparency across networks. However, a general purpose solution has a high product cost, complicates the application integration and deployment process, and lacks key features that facilitate the development, deployment, and management of converged applications over multiple networks. Fundamentally, both the general purpose and the “re-write” and “re-connect” solutions only compound the non-reusable “stove piping” deployment model and require intense integration work. The proliferation of stovepipes creates numerous management and cost challenges. Today’s solutions simply do not address the impact of the evolving network on applications and feature transparency.

 

 

A new application delivery environment within the telecom market is emerging. The industry is driving towards a service development and deployment model, which is independent of the evolving network. This new service environment will ensure applications are not impacted by the evolving network and ultimately, feature transparency is achieved. To create this new environment, a new purpose built network layer must be deployed to sit between the service node and the core of the network. It must be multi-service, multimedia in capability and inter-carrier in scope. It must provide network functionality such as presence, location, communication context, and service discovery to the applications. Also, it should support multi-applications from multi-vendors with an evolution path from currently deployed architectures to future architectures.

 

Deploying a purpose built network layer solution that provides network connectivity between current and new applications as well as existing and next-generation network elements is the answer. Today’s networks require a purpose built solution that is deployed independently from the network and applications while still keeping pace with the ever evolving network to ensure feature transparency. A new network element called an Application Session Controller (ASC) is being proposed to address the need for a new “application aware” network layer. It sits between the service node and the core network to provide and manage connectivity to the evolving network. It insulates the applications from the network via a programmable network abstraction engine, thereby providing the application specific call-control functions independent of each network. The ASC incorporates a number of open standard APIs, plus the signaling, media and feature inter-working between disparate networks that converged and consolidated applications require. It is scalable to support tens of millions of subscribers via a single system or via clustering and provides the necessary calls per second/transactions per second required for large-scale multi-network environments.

 

 

The Application Session Controller allows service providers to maintain a competitive edge with a purpose built application connectivity architecture, and ensures application feature transparency. This purpose built solution supports multiple application platforms/servers and eliminates costly network connection stovepipes. It results in increased ARPU by speeding time to market for essential voice, video and data applications and reduces CAPEX expenses by eliminating unnecessary additional general purpose network elements. The ASC also eliminates the need for application developers to continually customize their applications to access different networks, hence decreasing development efforts and increasing the availability of the application.

 

As service providers continue to expand their networks and increasingly offer converged applications, the current deployment models will not easily enable feature transparency. A new network element focused on insulating the applications from the evolving network enables true subscriber feature transparency.