Industry trends and challenges faced by operators
The implementation of national strategies including Industry 4.0 and Internet Plus is driving the traditional telecoms industry to transition towards internet integration, intelligence and scale customization. The industry upgrade towards intelligence and scale requires massive data moving to the cloud, which leads to the ushering in of a “cloud” era. This model calls for an innovative architecture featuring flexible and dynamic network resource configuration, highly-efficient resource utilization, as well as agile and smart service distribution to suit complex and diverse scenarios.
While operators have built large quantities of equipment rooms in their local networks and deployed lots of unshared voice, broadband and dedicated line equipment, the O&M is difficult and capex and opex remain at a high level. The vertically fragmented and chimney rigid network system as well as the complex and closed network architecture require high deployment costs but are less efficient, unable to meet the requirements of new service deployment. It is also difficult for operators to deal with the impact of the cross-boundary rivals.
With new emerging technologies, such as SDN/NFV, operators have new opportunities for changing this situation. But operators face challenges surrounding how to transform equipment rooms and equipment in legacy networks, make full use of legacy equipment room resources and migrate traditional networks to SDN/NFV architecture.
Multilayer DC is the direction of network re-architecture
In order to solve the above problems, to build a SDN/NFV-ready and cloudified network, re-architecture is the trend for network evolution. The next-generation network will make the data center (DC) the core, and central office (CO) re-architecture will be the pivot of network re-architecture.
The SDN/NFV-ready elastic network is based on a multilayer DC architecture (central DC, domain DC and edge DC). The multitude of localized edge data centers that are close to end users will become the core advantage and key asset for operators. Through re-architecting the legacy local CO equipment rooms, the edge DC will cover local networks, meeting the requirements of local service access and delivering ultra-wide bandwidth, enabling shared resource pool, dramatically reducing the quantity of equipment, driving down network capex and opex, providing more enriched and convenient value-added services for users, and bringing the potential of ICT service innovation to operators. The automatic management and agility of telecom networks as well as resource utilization will be greatly improved, network-cloud integration will be implemented and operators will possess the “elephant can dance” capability.
Fig 1 Network re-architecture with three-layer DC
Access network re-architecture and evolution
In the face of the soaring growth of bandwidth-hungry 4K, VR/AR and cloud computing services, the access network needs to redefine its functions and upgrade its performance to meet service and experience requirements. Flexibility, scalability and automatic resource allocation become the must-have capabilities of future access networks. In network re-architecture with three-layer DC, the access network closest to the end user is deployed below the EDC (edge DC), and the access equipment room acts as a remote EDC node and a small DC that meets government and enterprise, mobile, big video and IoT service requirements and provides the best service performance and QoE.
OLT is the core equipment of the remote EDC node
The OLT, as the key equipment in the access equipment room, needs to provide full-scenario multi-service access capabilities, and acts as a remote EDC node that supports network re-architecture and migration. Operators need to use SDN-ready programmable full-scenario OLTs to innovate their business model and provide new functions such as network slicing, VXLAN, and SDN Agent that separates control and forwarding. The OLT carries mobile BBU, dedicated government and enterprise, public and video services, and connects universal IT devices to provide storage, computing, video service processing and value-added mobile service processing capabilities, satisfying the requirements of multi-tenant and diverse cloud services.
Fig 2 Distributive EDC deployment
TITAN - a powerful next-generation full-scenario optical access platform
ZTE unveiled TITAN, an innovative next-generation full-scenario access platform oriented to network re-architecture at BBWF in October 2010. It is a cutting-edge optical access platform that supports network re-architecture and service innovation. ZTE TITAN can be deployed in the access equipment room as a remote EDC in the Spine-Leaf architecture, supporting flexible access of all types of services in the full range of scenarios. Meanwhile, ZTE TITAN supports network slicing, large L2 VXLAN connections and the SDN functionality with separated control and forwarding, facilitating OLT clustering and proximity scheduling. The platform also provides vONU and flattened convergence capabilities through the OTN ports or 100GE ports, simplifying the network hierarchy and facilitating the processing of latency-sensitive services.
Fig 3 Network architecture of remote EDC node