Deployment of the next generation ultra-broadband access network in the 5G era

In the 5G era, the demand for ultra-broadband access is becoming more obvious, and the rich services have put forward the ultra-broadband access network with three highs: ultra-wideband and on-demand characteristics. In order to adapt to network changes, building ultra-broadband and on-demand ultra-broadband access networks has become an urgent task for more and more operators. FiberHome Communications' layout of the next-generation PON will help operators accelerate the transformation of broadband access networks in the 5G era.

1. Business requirements for broadband access: "three highs"

In the 5G era, with the rapid development of mobile Internet and Internet of Things, the types of services are becoming more and more diverse. Among them, high-bandwidth video services represented by 4k high-definition and AR/VR video services have put forward "three highs" requirements for ultra-broadband access networks: high traffic, high concurrency, and high perception.

High traffic: The driving force behind 5G is the mobile Internet and the Internet of Things. According to relevant data, the number of terminals connected to the Internet will reach 100 billion by 2020, and the demand for bandwidth is increasing. The bandwidth demand for 4k video service bitstream is 5 times that of HD video. Similarly, VR/AR will also face bandwidth issues in the future. Ultra-broadband access is imperative.

High concurrency: With the development of mobile Internet, the number of mobile terminals has increased dramatically, reaching 1.7 billion worldwide in 2017. The increase in the number of mobile terminals has led to a surge in concurrent traffic of real-time 4K video and hot video. The existing access network bandwidth has a trend of being unable to support future bandwidth requirements, requiring technical support for higher bandwidth and reducing the access network bandwidth convergence ratio from 4:1 to 1:1 without convergence.

High perception: With the development of the network, customers' experience requirements are getting higher and higher, and they have higher requirements for speed, latency and video quality. For example, the bit error rate requirement for 4K video has increased by 100 times, VR requires a latency of less than 20ms, and the speed of watching videos must be as fast as the Internet.

2. Pain points of existing access networks

The current network still has deficiencies in bandwidth, platform architecture and pipeline flexibility, and cannot fully support the needs of ultra-wide and on-demand networks.

4K video is an important service in the ultra-broadband era, and its bandwidth requirements are several times higher than those of quasi-4K and 4K high-definition videos. For example, a single user needs 20Mbps bandwidth to watch ordinary 4K videos, 100Mbps bandwidth to receive 4K videos, and 800Mbps bandwidth to watch 8K videos. At the same time, video services are also very sensitive to latency and jitter, which puts higher requirements on the system's cache capacity and the concurrent processing capabilities of the equipment. The current 100Mbps (1Gbps in some areas) bandwidth network is far from meeting future bandwidth requirements.

The existing platform architecture is centralized. In the GPON/EPON 100M era, the traffic was relatively small, and the centralized architecture could basically cope with it. In the Gigabit access era and in the future, the traffic will increase by more than ten times. OLT needs to cope with the digital torrent brought about by it, and it must have the characteristics of "ultra-wide and ultra-large". If the centralized architecture is still used, many problems such as bandwidth bottleneck, congestion, and poor customer experience will occur.

In addition, the existing PON network is a rigid pipeline that cannot realize network resource slicing and cannot help operators to carry out multi-service intelligent operation. It cannot realize power division and domain division, and maintenance and management are difficult and complicated, and it does not have the ability to meet demand.

3. FiberHome plans to build next-generation access networks

In order to overcome the pain points of the existing network and build an ultra-wide, on-demand broadband access network, FiberHome has overcome technical difficulties in high-speed access networks, distributed architecture platforms, and virtual OLTs, and achieved an ultra-wide, on-demand network layout.

100G-PON ushers in the ultra-broadband future: IEEE has established an NG EPON research group, and the standard is named P802.3ca, which is mainly aimed at standardizing 25G, 50G, and 100GPON, and plans to officially release the standard in May 2019. ITU-T has also formed a 25G PON research group to study the improvement of single-wavelength rate. Therefore, 100G PON, which is characterized by a single-wavelength rate of 25Gbps, will become the mainstream direction of the next generation of PON. The product-level 100GPON prototype released by FiberHome in March 2016 has a single-wavelength rate of 25Gbps. The unidirectional system supports 4 wavelengths, achieving a high-bandwidth access capability of 4*25Gbps. The single-fiber capacity of 100G can provide users with gigabit and 10G fixed bandwidth access, and also meet the future 5G base station peak rate of at least 10Gbps mobile broadband access requirements, which will usher in the future of ultra-broadband.

Distributed forwarding architecture supports ultra-wide services, zero packet loss, and zero jamming: The distributed architecture, ultra-wide slot capacity, and ultra-large cache of the FiberHome distributed OLT platform AN5516 can realize independent processing and forwarding of service boards, upgrade continuous services, and zero network convergence capabilities; 200G slot bandwidth, 20,000 concurrent users, and support for 10GPON, 40G-PON, and 100GPON on the same platform, which can achieve smooth evolution of NG PON and protect the operator's existing investment; single-line card cache 16M, system cache 256M, and meet the requirements of zero packet loss and zero jamming for 4k video services. Therefore, the distributed forwarding architecture of the common platform is the best choice for future ultra-wide access.

OLT virtualization improves network operation and maintenance, and provides on-demand access: divide and access on demand, virtualize one OLT into multiple OLTs, and allocate different virtual OLTs to different services such as home, enterprise, and mobile communications for intelligent operation of multiple services, thereby helping to incorporate old OLTs, reduce the number of CO rooms, and reduce operating costs. Isolation of software and hardware resources is more secure and reliable. Different virtual OLTs have exclusive hardware resources to ensure high security of dedicated lines and self-operated services.

4. Conclusion

Compared with the 4G era, 5G has put forward higher requirements in terms of bandwidth capacity, latency and network capabilities. The layout of FiberHome's next-generation PON: 100G PON, distributed same platform and virtual OLT, supports ultra-high bandwidth, smooth evolution of different PONs and network resource slicing capabilities to provide operators with ultra-broadband and on-demand networks, meeting the "three highs" requirements of the business for the network. At the same time, it protects the operator's existing investment and intelligent operation, and helps the operator's transformation from gigabit access to ultra-broadband access in the 5G era.