Beyond 800G: Global Standardization Efforts Accelerate for 1.6T and B1T Optical Transmission

Beyond 800G: Global Standardization Efforts Accelerate for 1.6T and B1T Optical Transmission

Source: CFO (China Fiber Online) - Adapted from an original article by ZTE Technologies

Driven by the AI computing revolution and data center demands, optical transmission technology is rapidly advancing towards higher speeds and greater bandwidth. While 400G has entered its commercial era and 800G standards for short-reach and metro applications are maturing, the global focus is shifting to the next frontier: rates beyond 1 Terabit (1.6T and B1T). International and domestic standards bodies are actively shaping the future of ultra-high-speed optical networks.

Key Standards Organizations and Their Focus

The landscape for high-speed optical transmission standards is defined by several key organizations:

• ITU-T SG15: Focuses on optical system standards and B1T OTN (Optical Transport Network) frameworks.

• OIF (Optical Internetworking Forum): Leads in standardizing coherent optical modules (e.g., 800G/1.6T ZR/ZR+) for line-side interfaces and data center interconnects.

• IEEE 802.3: Defines high-speed Ethernet client-side interfaces (800GE/1.6TE).

• CCSA (China Communications Standards Association): Addresses domestic requirements, with TC6 focusing on WDM systems and optical modules, and other committees working on satellite laser communications and quantum encryption.

Progress on 800G and the Leap to 1.6T

International Efforts:

• ITU-T SG15 Q6 is standardizing 800G metro DWDM, with completion expected by 2026. Future work will explore 1.6T standardization, C+L band expansion, and Hollow-Core Fiber.

• OIF has cemented its leadership by completing 800G ZR/LR standards. It has now officially entered the 1.6T era with three key projects:

  • 1.6T ZR: Targeting 80-120km reaches using single-wavelength PM-16QAM in the C-band (Expected completion: Q3 2026).

  • 1.6T ZR+: Aiming for long-haul reaches (1000-2000km) using dual sub-carriers and the C+L band (Expected completion: End of 2026).

  • 1.6T Coherent Reduced (CR): Promoting simplified coherent technology for broader adoption.

• IEEE 802.3 is progressing on 800G/1.6T Ethernet interfaces, with the 802.3dj (200G/lane) project on track for a September 2026 release.

Domestic Leadership in China (CCSA):

• CCSA TC6 WG1 has completed standards for 400G ultra-long-haul WDM, fueling its commercial deployment. It has now initiated research and standardization for 800G long-haul, S+C+L band expansion, and 1.6T systems, positioning China at the forefront of advanced DWDM standardization.

• CCSA TC12 is pioneering standards for 100Gbps satellite laser inter-satellite links, marking a significant step for high-speed optical communication from terrestrial to space applications.

A Glimpse into the Future: B1T OTN Standardization

The ITU-T is making breakthrough progress on B1T OTN, designed for efficiently carrying high-bandwidth services like Ethernet. The new standard, planned for July 2026, is built on two core principles:

1. Simplified Architecture: B1T OTN drastically reduces the complex multi-layer hierarchy of traditional OTN, streamlining network architecture and operations.

2. Industry Commonality: It aims to reuse and align with key technologies from OIF's ZR standards (e.g., mapping mechanisms), promoting a shared supply chain and reducing costs.

Conclusion

The standardization roadmap for ultra-high-speed optical transmission is clear. While 800G for metro areas is becoming mature, the global race is on for 1.6T. Technologies like advanced modulation formats, C+L band integration, Hollow-Core Fiber, and satellite optical communication are set to define the next generation of networks, with standards bodies working in parallel to turn these possibilities into commercial realities.