Building all-optical green cities with ubiquitous optical technology

Fiber is the greenest connectivity medium to date and the best foundation for green cities.

By Simon Lu, President, Transmission Network Domain, Huawei
Lu Yiquan

Building green connectivity is a central mission for the entire ICT industry. According to Huawei’s Global Industry Vision (GIV), by 2025 the average carbon emissions per ICT connection will fall by 80 percent and the ICT sector will enable global energy savings and reductions in emissions that far exceed the energy and emissions the industry itself consumes and produces.

Of the connectivity methods we’ve used to date, optical fiber is the most eco-friendly, offering unparalleled advantages in bandwidth, latency, anti-interference, and reliability. Compared with copper, it offers ten times the bandwidth, one-tenth the latency, and 60 to 75 percent lower energy consumption.

Reshaping optical transmission sites is a major direction for innovation across the entire industry. As a leader in the field, Huawei is designing green optical network products to minimize energy consumption in optical transmission sites.

9-in-1: Optical cross-connect for 3D backbone

New types of services and network cloudification are driving a shift in network traffic from north-south to east-west, characterized by frequent irregular and random bursts of traffic. This has led to extensive data exchanges between network nodes and a high level of uncertainty in network services, which calls for efficient traffic grooming.

In the past, reconfigurable optical add-drop multiplexers (ROADMs) have mainly been used to handle cross-connect scheduling for coarse-grained services. However, traditional ROADMs require many optical fibers to connect multiple modules, resulting in a large number of fiber interconnects in equipment rooms, increasing O&M difficulty and taking up a large amount of space.


Huawei has launched the industry's only commercially available optical cross-connect (OXC) product – the OptiX OSN 9800 P32. Harnessing technological breakthroughs like all-optical backplanes and highly precise liquid crystal on silicon (LCoS), a single device boasts Pbps-level cross-connection capacity. It is able to replace nine traditional ROADMs, reducing the footprint in equipment rooms by 90 percent and power use by 60 percent.

OXCs also support up to 32-degree optical cross-connect scheduling. OXCs on multiple optical transmission nodes also help build a 3D backbone network, simplifying backbone transmission network architecture and realizing architecture-level energy savings across the entire backbone network.

Huawei has been working with leading operators globally, including China Mobile, China Telecom, China Unicom, and Indonesia's XL Axiata, to innovate and deploy OSN 9800 P32 products on 50 commercial networks, covering backbone transmission sites and metro core sites.

6-in-1: Optical-electrical integration for MANs

When it comes to metropolitan area network (MAN) optical transmission sites, the explosion in service requirements from 5G, HD video, and enterprise leased lines has created an immense challenge for MAN architecture. To meet the requirement to carry multiple services on integrated bearers, operators are focused on best using the limited space in MAN equipment rooms and minimizing energy consumption.

Huawei's OptiX OSN 9800 M24 provides an industry-leading integrated optoelectronics platform. Incorporating six functions into one device – optical, ponder, SDH, ETH, ODU, and OSU – it supports full granularity of service access from 2 Mbps to 400 Gbps, cuts the equipment room footprint by 70 percent, and uses 30 percent less power.

The large-scale deployment of OSN 9800 M24 in MANs can flatten MAN architecture, decreasing the amount of equipment required, maximizing space utilization, and reducing power consumption in MAN equipment rooms by integrating bearing for multiple services. Huawei has shipped thousands of OSN 9800 M24 optical transmission products worldwide, which have been deployed commercially by operators such as CTS in Malaysia.

X in 1: All-optical anchor point for unified bearing

As data centers continue to move closer to the user side and network architecture oriented towards data centers becomes mainstream, the service volume of the access layer has risen sharply at integrated service access sites, especially with the rapid growth of services like 5G, gigabit broadband, and gigabit enterprise. As such, integrated service access sites have become more important and operators are prioritizing maximizing the utilization of limited site resources to support full-service development. And with the requirement to carry multiple high-value services, operators must maximize network reliability, transmission performance, and automated O&M capabilities, while lowering space and power use in equipment rooms.

Huawei's OptiX OSN 1800 V Pro slashes the equipment room footprint by 75 percent and power consumption by 50 percent. It also boasts access for multiple services, including SDH, PDH, SONET, SAN, and SDI, for full-scenario coverage. Indoor and outdoor cabinets and OLT/BBU shared cabinets are supported, making it suitable for installation in all cabinets. The product meets bearer requirements for high-performance transmission as well as eco-friendly energy efficiency in the integrated access site.

Adopting OptiX OSN 1800 V Pro will help operators carry 5G fronthaul bearers, premium leased-line bearers for government and enterprise, UHD video bearers, and other such services over a unified platform, and build all-optical anchor points, greatly reducing the number of fiber connections at integrated access sites, accelerating the removal of SDH equipment from the network, and slashing the number of switches. 

It will thus promote overall energy-saving in integrated access sites.

Building green all-optical cities

From the 3D backbone network and simplified MAN to all-optical anchor points, leveraging end-to-end OXC and OTN equipment will help build all-optical city target network architecture that covers all transmission sites in the city. This will provide one-hop direct connection for enterprises, households, and individuals in the city using more eco-friendly optical connectivity.

The all-optical target network promotes the flattening of the entire bearer network, helps simplify network architecture, and integrates and co-opts multiple types of complex legacy networks, thus facilitating energy conservation across the entire urban transmission network.

To help end users provide higher-quality connection services, Huawei has also launched OptiXstar C800, the industry's first OTN CPE product. The plug-and-play device is the size of a book and offers less than 30 watts overall power consumption. It can fully co-opt old SDH and MSTP leased line services, helping enterprise clients to switch out multiple more energy-hungry devices from their equipment rooms, helping end users conserve energy.

With the wide adoption of eco-friendly optical connections across the industry, Huawei is promoting end-to-end innovation across the entire optical network to maximize its value. We’ve launched a series of Liquid OTN products, the first commercially available in the industry. They refine service bearer granularity from 1 Gbps to 2 Mbps, expanding the number of connections a hundredfold and meeting the service bearing requirements for SMEs and large enterprises, households, and individual users alike.

Ubiquitous optical connectivity enables ubiquitous ultimate experiences. The all-optical target network will accelerate cities' digital transformation; boost service experiences for every business, household, and subscriber; and help all industries achieve energy efficiency with green optical networks. 

Thus, we will move into the era of green all-optical cities.