Core Network Construction in Mobile Internet Era

Mobile broadband services are penetrating every aspect of our social life, and the mobile internet industry is booming. We have imperceptibly entered a new era of mobile information and communication technology (M-ICT).
Operators have been the traditional providers of mobile internet access pipelines, and in the M-ICT era they are facing challenges on all levels. On the one hand, hit by OTT services, the traditional voice and SMS services are shrinking rapidly. Emerging social mobile apps such as WeChat, Skype, and Facebook are favored because they are free and enrich user experience. They have edged out traditional communication modes in only a few short years and are becoming the communications tool of choice. This has led to a sharp decline in revenue for traditional telecom operators. On the other hand, the existing innovation models of mobile internet are independent of mobile networks and operators. Therefore, operators have been reduced to pipe providers and are not reaping the benefits from active mobile internet innovation. Moreover, compared to IT networks, traditional telecom networks have specialized equipment, which implies high construction costs, complex O&M, and closed service modes. Operators are faced with the dilemma of dwindling revenue and large expenditure.
To reverse the situation, operators have no way out but to proactively reform.
Currently, operators all over the world are making various attempts, hoping to accurate positioning themselves in the transformation to gain momentum and develop sustainable.
To compete with OTT players, operators have launched IMS-based VoLTE and RCS services to replace traditional voice and SMS. Compared with traditional voice and SMS, VoLTE and RCS provide HD voice and multiple media types. Compared with OTT services of mobile internet, VoLTE and RCS provide better quality, wider interoperability and better security. This guarantees excellent user experience. In August 2012, Korean operators including SK Telecom and LG U+ took the lead in launching VoLTE. After two and a half years of market cultivation and technological improvement, VoLTE is now flourishing. Verizon, AT&T, and China Mobile have jumped on the VoLTE bandwagon. Commercial VoLTE services are continues to grow and mature. 
To become more than mere pipe providers for mobile internet, operators are constantly exploring new areas and means of development. Operators are finally staking out their territory in a trial-and-error process. Only by offering differentiated value-added services to mobile internet customers can they generate sufficient revenue. Verizon has launched different services for individuals, group customers and governments. Domestic operators are proactively pushing forward the backward cooperation with CPs and SPs, such as the directional flow package service launched by China Unicom, and 800 packet service and video assurance services that are being promoted by China Mobile. In this process, operators are finding that the existing telecom network architecture is too rigid for changeable service models and scenarios of mobile internet. They hope to better use network capability to obtain value-added benefits. Therefore, various traffic operation solutions are launched in the industry. ZTE has proposed a data-intelligence network solution that provides a full set of differentiated services by introducing capability-opening interface and that uses big-data analysis and a closed-loop protection system to guarantee user experience. This solution is a bridge leading to collaborative innovation in mobile internet.
To address the problems of high TCO, enclosed old servicers, and long introduction period of new services, operators are striving to seek better solutions. Fortunately, emerging virtualization technology and SDN technology enable operators to see daylight.
Virtualization technology virtualizes the computing, storage, and network of an IT server into a plurality of different virtual machines for different users. By introducing network function virtualization (NFV) in telecom networks, specialized equipment and advanced hardware resources are not necessary and hardware procurement costs are reduced. NFV can also promote the sharing of network physical resources and improve the utilization of hardware resources. In addition, virtualization and universalization of telecom hardware opens a door to third-party services. By this token, the virtualization technology facilitates the separation between software and hardware of telecom equipment, thus making the telecom networks more flexible and open.  
SDN technology is derived from IP network routing control. Traditionally, changing network topology required route reconfiguration for a large number of routers in the network. However, by separating the control and forwarding of routing devices, SDN can change network topology through centralized configuration in the control plane and issuing to the forwarding plane for implementation. This simplifies the maintenance of network routing to the greatest possible extent. Moreover, it controls the routing of service flows by introducing third-party applications through open interfaces. In telecom networks, SDN technology is introduced automate network deployment and realize service-based flexible component scheduling. It is introduced to mobile network nodes such as SAE GW so that the overall network can be made flatter and packet forwarding can be made more efficient.
In summary, combining NFV and SDN technologies makes telecom networks more intelligent. The networks can be customized in real-time according to different customer needs and adjusted adaptive depending on the network status. NFV and SDN technologies represent the future of telecom networks. Nowadays, many standards organizations are propelling the standardization of NFV and SDN applications in telecom networks. Many operators are verifying NFV and SDN technologies. Vodafone, Deutsche Telecom, and China Mobile are actively executing virtualization validation for IMS and EPC networks. Telefonica even announced at MWC 2014 that it would launch the NFV-based UNICA solution on its group networks in order to completely redesign its mobile and fixed networks. Telefonica is expected to virtualize 30% of its new networks by 2016.
In the mobile Internet era, operators need to strategically transform themselves. However, traditional networks are not conducive to this transformation. Operators need new networks with new communication and traffic management capabilities as well as an advanced virtualized architecture. To beat the competition, operators must find their own path of sustainable development.