As network traffic keeps growing, service providers, internet exchanges, and data centre operators need faster, more efficient solutions to keep up. That’s where 400GZR and 400GZR+ come in—two high-speed optical networking technologies designed to handle increasing data demands.
While both offer powerful capabilities, 400GZR+ takes it a step further, delivering greater reach beyond 120km* and added flexibility for evolving network needs. Let’s explore how these solutions compare and why 400GZR+ might be the smarter choice for the future of modern networks.
What is 400GZR?
400GZR is a pluggable transceiver standard designed for high-speed, short-distance optical transport. Based on Ethernet and OTN (Optical Transport Network) interoperability, it is primarily used for data centre interconnect (DCI) and short-reach metro networking applications.
Key Features of 400GZR:
- Optimised for distances up to 120km1)
- High-speed connectivity (400Gbps) over a single tunable wavelength
- Interoperability with Ethernet and IP networking
- Cost-effective, leveraging industry-standard pluggable form factors
- Ideal for Data Centre Interconnect (DCI) applications
Despite its benefits, 400GZR has limitations when it comes to longer-distance transmission and flexibility in different networking environments.
What is 400GZR+?
400GZR+ is an enhanced version of 400GZR, designed to support longer distances and increased network flexibility. While it builds on the foundation of 400GZR, it incorporates additional features that allow for greater reach beyond 120km and improved performance across various network architectures.
Key Features of 400GZR+:
- Supports distances beyond 120km, up to 500km2)
- Higher link budget for improved performance in long-haul and metro networks
- Greater flexibility in modulation schemes for varying distance requirements
- Backward compatibility with existing IP and DWDM networks
- Optimised for a mix of Data Centre Interconnect (DCI) and Metro/Regional transport
By extending the distance capabilities, 400GZR+ enables service providers and enterprises to deploy more scalable, cost-effective and resilient networks.
Key Differences: 400GZR vs. 400GZR+
| Feature | 400GZR | 400GZR+ |
| Distance Support | Up to 120km1) | Up to 500km2) |
| Application | Short-reach DCI & Metro | Metro, Regional, Long-Haul |
| Flexibility | Fixed modulation | Multiple modulation schemes |
| Link Budget | Lower | Higher, supports greater optical loss |
| Interoperability | Ethernet/IP | Ethernet/IP + L1 Transport options |
| Use Case | Short-range connectivity | Extended reach & multi-use networking |
While 400GZR is an excellent solution for short-range high-speed networking, 400GZR+ significantly extends its capabilities, making it a better fit for service providers handling diverse traffic demands over longer distances.
Key Benefits of 400GZR+
For organisations requiring reliable, high-speed connectivity over extended distances, 400GZR+ provides several advantages over standard 400GZR:
- Extended Reach beyond 120km2
One of the most significant advantages of 400GZR+ is its ability to handle distances well beyond the 120km limit of 400GZR. This is essential for:
- Metro and regional connectivity where data centres and networking hubs are spread across multiple cities.
- Enterprise networks requiring secure, high-bandwidth connections between headquarters and remote sites.
- Service provider networks needing cost-effective, scalable long-haul transport.
- Greater Link Budget for More Resilient Connections
400GZR+ supports a higher optical link budget, which means better performance even when dealing with signal attenuation over long distances. This makes it a more resilient solution for challenging network environments, including those with multiple fibre splices or variable infrastructure conditions.
- Enhanced Flexibility with Multiple Modulation Schemes
Unlike 400GZR, which operates with a fixed modulation scheme, 400GZR+ offers multiple modulation options to optimise transmission based on:
- Distance requirements
- Power efficiency needs
- Optical Power and OSNR budgets
This increased flexibility allows network operators to dynamically adjust performance to match changing traffic and infrastructure demands.
- Seamless Interoperability with Open Networking & Line Systems
400GZR+ is designed to work seamlessly with open networking solutions and Dense Wavelength Division Multiplexing (DWDM) infrastructure, including Layer 1 transport solutions. This means:
- Easier integration with existing optical networks without requiring expensive overhauls.
- Cost-efficient scalability, allowing network expansion without significant infrastructure investment.
- Future-proof networking, as 400GZR+ adapts to evolving traffic demands and emerging technologies.
- Transponder and Muxponder solutions for Layer 1 transport solutions.
- Cost Savings & Scalability for Growing Networks
While both 400GZR and 400GZR+ are cost-effective compared to legacy optical networking solutions, 400GZR+ offers better long-term value by enabling organisations to scale their networks without incurring the high costs of traditional transponders or additional network layers.
Use Cases: When to Choose 400GZR+ Over 400GZR
Choose 400GZR when:
- You need short-distance, high-capacity connectivity (e.g., within a metro area, between nearby data centres).
- Where Cost savings into supported environments are priorities.
- Your existing infrastructure is optimised for short-reach DCI.
Choose 400GZR+ when:
- Your network requires extended reach beyond 120km, up to 500km2.
- Flexible Layer 1 transport options are required.
- You need greater optical budget to handle signal degradation over longer distances.
- Flexibility is key, allowing for optimised modulation and performance tuning.
- You want seamless integration with open networking and DWDM environments for future-proof scaling.
As network demands continue to grow, selecting the right optical networking technology is critical for long-term scalability and efficiency. While 400GZR remains an excellent choice for short-range, high-speed connectivity, 400GZR+ offers the additional reach, flexibility, and resilience needed for metro, regional, and long-haul deployments.
By investing in 400GZR+, organisations can future-proof their networks, reduce infrastructure costs, and ensure seamless scalability as bandwidth requirements increase.
Ready to explore how 400GZR+ can optimise your network? Contact IDS to learn more about deploying flexible, high-speed optical networking solutions for the future.
1)Note: To achieve 120Km, a suitable amplified line system such as the DCP-M40-C-ZR+ is required
2)Note: To achieve extended distances a suitable amplified line system such as the DCP-M40-C-ZR+ and DCP-R-9D-CS are required. Distances of up to 2000Km are achievable with 100G QPSK
Image source: Freepik – alicephoto
