The advent of digital life has led network traffic to increase rapidly, and users to have more demanding requirements for experience. Operators have incorporated video, 5G, and private line services into key development strategies for planning and building transport networks over the next five years. To provide optimal user experience, reduce network operating expenses (OPEX), and improve their return on investment (ROI), operators generally choose to construct ultra-broadband and intent-driven networks by deploying OTN to CO at the metro edge.

New Services Have Rigid Requirements for High Bandwidth and Low Latency

UHD video services need high bandwidth and low latency. According to forecasts, the proportion of 4K video traffic as part of total network traffic will increase from 2% in 2017 to 20% in 2021, and video services are driving a 25% compound annual growth rate (CAGR) in network traffic. The switching and interaction of 4K video and AR/VR services create demanding requirements for low latency. For example, the E2E latency of 4K videos must be lower than 20 ms, which is more demanding than the requirement for 50 ms E2E latency of HD videos.

5G services need high bandwidth and low latency. The average bandwidth of 5G base stations will exceed 1 Gbps, with a peak value of about 10 Gbps, which is 10 times as high as the bandwidth on 4G networks. Some new 5G services require an E2E latency of lower than 10 ms, limiting transport latency to no higher than 5 ms.

Private line services need high bandwidth and low latency. Digital development in various industries has driven enterprise private lines to develop from megabit-level to 100M, GE, 10GE, or even 100GE. For example, 100GE is a basic service granularity for DC interconnection. In the financial industry, 303 transactions can be performed in one ms. This means that a decrease in latency of one ms allows for the transmission of 303 additional transactions, which can boost the overall transaction amounts by hundreds of millions of US dollars per year.

The most basic requirements for an optimal user experience are high bandwidth and low latency. How can a transport network be built that offers optimal experience with high bandwidth and low latency?

OTN to CO, Building Ultra-Broadband and Intent-Driven Transport Networks That Offer an Optimal Experience

Metro CO is an integrated service access point of the network. Home broadband, mobile, and private line services are all aggregated to the CO, making the CO increasingly important. Deploying OTN to CO has become a common practice of many operators for the following reasons:

• OTN improves network capacity by 100 times. The construction of transport networks must meet the traffic requirements over the coming 3 to 5 years. With the development of video and 5G services, the traffic of each CO will typically reach more than 100G. OTN provides a bandwidth of 100 Gbps or higher and increases the system capacity up to Tbps, which not only satisfies current requirements but also fully supports future smooth evolution.
• Simplified network architecture based on OTN provides an optimal user experience. Traditional networks use a multi-layer architecture. The packet loss rate and latency are high in the process of hop-by-hop service forwarding, making user experience difficult to guarantee. OTN uses electrical-layer ODUk or optical-layer wavelengths for pass-through transmission, which provides a flattened and simplified architecture, reducing the number of network layers. In this way, services can be directly transmitted from COs to core routers (CRs) in one-hop connection mode with zero packet loss and minimum latency, providing an optimal user experience and improving operator competitiveness.
• MS-OTN is configured to carry various services, enabling multi-service transport over the same network. In traditional solutions, different services must be carried by different networks. For example, private line services and traditional voice services are transmitted through SDH networks, and FBB/MBB services are transmitted through data networks. MS-OTN implements unified cross-connection grooming and line transmission of VC, packet, and ODUk services, so that various services including Ethernet, large-granularity private line, TDM private line, and DCI services can be carried over the same network. This enables operators to provide multi-service transport over the same network, accelerating network convergence and reducing TCO.
• TSDN is enabled to achieve intelligent management. Optical networking based on transport software-defined networking (TSDN) has open and elastic features and supports various apps and service innovations. It automatically adapts to transmission rates and distances in various scenarios, intelligently selects routes based on latency policies, and implements unified grooming and intelligent management of cross-layer and cross-domain network resources.

OTN to CO with MS-OTN and TSDN enabled is the best solution for building an ultra-broadband and intent-driven transport network that offers an optimal user experience. This solution will adapt to the continued development of various services, providing a better ROI.