The challenges and demands that transport network is facing in new era

With the large-scale deployment of 4G and broadband access bandwidth escalating, the data traffic is growing exponentially. Meanwhile, with the development of Internet and mobile Internet, the network business has become increasingly diverse and the transmission network is facing the development requirements of architecture optimization, capacity increasing, transport ability upgrading and intelligent control. This means the further technological innovation is needed.

POTN (PTN + OTN) is the ultimate way of the future evolution

With the promotion of PTN and OTN applications, the needs of large capacity and efficient transmission in the metro & core layers in multiple cities normally can be satisfied by using the way of PTN and existing WDM / OTN back to back connecting. But this will undoubtedly increase the difficulty of operator's network operation and maintenance, and also increase the transmission equipment types, the energy consumption and the network overall costs. Furthermore, with the increase of business and traffic, the network positioning of OTN has become wider and wider, and the border between OTN and PTN has become increasingly blurred. To this end, POTN comes. POTN is based on the integration and innovation of PTN and OTN technologies, both available from PTN evolution and OTN evolution. POTN with existing PTN and OTN is the coexistence and evolution relationship. POTN contributes to reduce the construction costs and O&M costs for operator’s network. Through the integration of PTN and OTN achieved in one sub-frame, operators can solve many issues, such as small floor space and tight power supply.

POTN transport network can be applied to the operator's network: backbone, core-layer, aggregation-layer and access-layer. POTN has the natural ability of interconnecting with PTN and OTN networks. On the one hand, POTN has MPLS-TP packet transfer capability, can achieve the bandwidth convergence based on statistical multiplexing. On the other hand, POTN has the strong channel capacity of OTN, which can carry a variety of services together and completely eliminate the effects between them. This provides the basis for mobile backhaul, government and enterprise services and FTTH services on the same physical network. POTN, by combining packet transport and OTN channelization capability, achieves a three-dimensional transmission pipeline scheduling system (just as the overpass traffic control system). This can help to reduce the network congestion and enhance the multi-service carrying capacity and the quality of services.

POTN makes the network more flexible and open

POTN is not only the integration of optical network and IP network, but also adds SDN into the optical network. This allows POTN achieve the separation among control, forwarding and application from the architecture. SDN can be realized by increasing control and App application in POTN, to achieve the change of network from closed to open, and making the network more intelligent. At the same time, it offers an open northbound interface, through a centralized network management controller to enhance the network intelligence, to simplify multi-layer network operation & maintenance and to solve the interconnecting problems between multi-vendor’s equipments. In China, the China Communications Standards Association (CCSA) and OIF have published POTN relevant technical standards, the mainstream chip manufacturers, like PMC, BCM, have released related chip series. China Mobile increased Central Purchasing models and functional test requirements of POTN in the PTN Central Purchasing in 2014, obtaining the support from mainstream manufacturers. POTN is a multi-layered network forwarding technology, can achieve intelligent traffic control and network abilities development by introducing SDN control architecture. Since SDN separates the control protocol and forwarding plane, it helps POTN expand its application range, specifically international applications. Currently some overseas markets have showed great interest to POTN products.

The achievement of POTN networking solutions

POTN solution should be fully optimized based on PTN and OTN combined with practical applications. It is not the simple function stack of PTN and OTN, but the deep organic integration of them. POTN solutions of ZTE for example, first in forwarding plane, POTN products bring into a common switching matrix, to achieve the unity switching and function integrated of PTN and OTN on a single platform. Using Hybrid line card technology, it achieves the integration on line side, the flexible scheduling and free conversion of PTN packet services and ODU sub-wavelength services. In order to simplify the multi-layer network architecture, PIC technology has been added into the optical layer, to complete the WDM functionality. This improves equipment integration, avoids complex planning and operation & maintenance of WDM and provides SDH-Like operation & maintenance capability. Meanwhile the ETH layer is removed to reduce mapping complexity and to improve the efficiency of transmission. Such as, for 64-byte services, the package carrying efficiency of POTN is 20% higher than PTN. In network protection, POTN has ring protection based on MPLS-TP, and improves ring protection performance by rich alarming tests of OTN. In addition, POTN uses SDN-oriented control architecture to achieve the isolation among control, forwarding and application. To outside, it offers an open northbound interface, through a centralized network management controller to enhance the network intelligence, to simplify multi-layer network operation & maintenance and to solve the interconnecting problems between multi-vendor’s equipments. About the evolution of SDN, the smooth evolution from existing PTN network to POTN is also feasible. For hundreds of thousands of existing PTN equipments, we can use the centralized network management system to control them. And for new equipments, we can add new controller and use standard interface for centralized control. Over centralized network management and control, we can add new unified collaborative synergy layer to achieve the SDN evolution of entire PTN  network.


POTN is the deep integration and innovation of PTN and OTN technologies, which greatly enhances the transmission network capacity and performance in big data era. POTN is breaking the barrier of multi-layer network, and reducing the network construction and operation & maintenance costs. POTN solution will provide a broad platform for long-term development of a variety of businesses. YINGKE will commit to providing customers the best POTN solutions in a long-term, to help them solving the problems and challenges of transition in the mobile Internet era.

1998-2021  Wuhan YINKOM Telecommunication Technologies Co., Ltd.  All rights reserved