Transformation Oriented Core Network Development and Evolution

The transition from Stone Age to Bronze Age gave birth to civilized societies and greatly liberated the productive forces in those societies. This is often considered the most important technological revolution in human history. Such a revolution is also happening in today’s mobile communications as mobile services move from voice to data. The telecom revolution is having a great influence on operators and equipment suppliers, impacting the long-term survival and development of their core network products.

As the mobile Internet era approaches, operators are no longer core players in the service value chain. They are becoming pipe providers and the foundation of their existence is being shaken. Both traditional equipment suppliers and operators are now confronted with unprecedented difficulties and challenges.

Development Strategy for Core Network

Seizing opportunities and seeking a Blue Ocean strategy is the only option for equipment suppliers and operators. ZTE has stuck with the principle of “three integrations and two transformations” in developing its core network products and has achieved significant results.

Three Integrations

■    Multiaccess integrated and flat ‘smart pipe’ solution

■    Integrated voice and multimedia control network

■    Unified and integrated data management

Two transformations

■    Transformation from closed telecom structure to integrated telecom and IT architecture

■    Transformation from product centred to service centred, from function oriented to user experience oriented

With a terminal-pipe-cloud architecture, a core network incorporates smart pipe layer and network control layer, as shown in Figure 1. The smart pipe layer is the core of a smart packet network that provides intelligent control over various wireline/wireless access and bearer layers. The network control layer controls IMS, CS voice, and multimedia services in an integrated way, and unifies user data management. More importantly, it is an open platform for developing comprehensive network computation and storage capabilities. In this way, the application layer can utilize information and capabilities to help operators provide Internet application services and platform support for enterprise cloud computing.

In the transformation from service control to application capability provision, the core network acts as network middleware that abstracts infrastructure resources, network capabilities, and basic functions for all service applications. As its service control function is weakened, the core network is evolving into an open platform that provides leased capabilities services.

Building a “Diamond Grade” Smart Pipe

The rapid growth of mobile Internet had generated great demand for smart pipes. Offering an experience beyond user expectation is essential to the core competitiveness of pipe providers. To really satisfy an operator’s needs, a smart pipe must conform to the 4Cs of diamond quality: 

■    Carat weight: “Carat weight” bandwidth provides high bandwidth efficiency, flexible bandwidth expansion, and meets the challenge of bandwidth explosion in the mobile Internet era;

■    Clarity: Clean and visible communication pipes give providers insight into hot services and user behaviours. They are the basis for making operational decisions. Clean pipes with antivirus function also protect user security;

■    Color: Extremely fast, colorful, seamless access experience is provided to end users, and exclusive consulting services are provided to enterprise users;

■    Cut: Low-value traffic is cut out to ensure quality and perfect service for high-value traffic. “Diamond grade” smart pipes are built to create maximum value.

To fulfil the four Cs of diamond-quality smart pipes, ZTE has rolled out ZSP―a complete smart pipe solution that contains three sub-solutions: Optimized Operation and Management Solution (ZOOMs), Effective Routing and Offload Solution (ZEROs), and Content Optimizational Intelligent Network (zCOIN). These aim to improve user experience at lower cost.

■    ZOOMs transforms traditional naked pipes into visible, manageable, and controllable colourful pipes from the perspective of terminals, users, time, locations, services, and access modes. This maximizes pipe efficiency in a given bandwidth.

■    For long-term network development and smooth evolution, ZEROs adopts innovative technologies―GRP and MAB―for multiaccess bind capability and flat network structure. This allows low-cost traffic offload and expands bandwidth without changing existing network architecture.

■    zCOIN adopts content storage, compression, aggregation technologies as well as unilateral TCP optimization and end-to-end flow control to improve mobile Internet user experience. To offer a complete wireless application delivery solution, optimizations are made to address the last mile access bottleneck. QoS-based content delivery is also implemented along with Policy and Charging Control (PCC). zCOIN changes the traditional forward charging mode and builds an open pipe platform that helps operators obtain more revenue from the Internet.

Building a CS-IMS Converged Service Control Network

Despite a decline in both mobile and fixed voice revenues, voice service is still an important percentage of operator revenue. Traditional mobile softswitch will continue to play an important role in voice services.

Currently, major IMS applications are driven by the fixed VoIP market―where standard VoIP services are provided and Class 5 switches are replaced. As mobile operators evolve towards full-service provision and new wireless technologies (HSPA+, WiMAX, and LTE) are used, wireless VoIP and multimedia services have become a focus of attention of operators.

The two modes of voice service delivery need to coexist and evolve over the long term. Due to the aging and high TCO of existing mobile softswitch equipment, operators seek to adopt new-generation equipment utilizing high integration and low-TCO IT technology for building their networks. Because numerous IMS devices are used, their interfaces are quite complicated. This results in difficult equipment maintenance and high operation costs. Therefore, it is imperative to adopt a highly-integrated new-generation platform that allows for full convergence of CS and IMS. 

ZTE has developed a Voice & Video over Any-access solution (zVOA) that can help operators achieve sustainable network development while enhancing competitive edge of existing networks. Using zVOA, the traditional CS voice services and IMS services can be operated in a unified manner, and various multimedia and voice services over broadband access can be expanded by leveraging the advantages of the CS network. Based on ZTE’s advanced ETCA hardware platform and TULIP middleware platform, zVOA is fully compatible with all standard CS and IMS interfaces. It uses virtualization and cloud computing technologies to introduce intelligent Controller eXtensive (iCX) and integrative Media Gateway (iMG). iCX integrates functions of control plane network elements such as CSCF, MGCF, MSC, MSS, MMTel, AGCF, mAGCF, and MRFC, while iMG integrates functions of media plane network elements such as MGW, MRFP, and VIG. By inheriting traditional CS functions and using standard IMS implementation, zVOA provides VoIP and multimedia services with carrier-grade QoS. iCX and iMG with unified software and hardware platforms support smooth upgrade from MSC and MGW to mAGCF, CSCF, MMTel, and MRFP. This helps operators with unified operation and smooth evolution.

Conclusion

Facing network transformation, operators are seeking to develop smart pipes for their core networks. ZTE has rolled out ZSP―a complete smart pipe solution that helps operators build low-cost, best-experience diamond-grade smart pipes that support sustainable development. With the growth of mobile Internet, the transformation concept of platform + pipe will certainly be strengthened. This is the driving force for long-term development of core networks. 

CS and IMS will continue to be major contributors to service revenue in the long run. Assisted by iCX intelligent controller and iMG integrative media gateway, zVOA will help operators provide quality application services to individuals and enterprises, and rise to the challenges of mobile Internet in the telecom field.