QSFP28 DD (Quad Small Form-Factor Pluggable Double Density) transceivers are designed to provide high-speed data transmission capabilities with improved port density compared to standard QSFP28 modules. Here are the key features of QSFP28 DD transceivers:

Higher Data Rates: QSFP28 DD transceivers support higher data rates compared to traditional QSFP28 modules. They are designed to handle data rates of 200 Gbps or more, enabling faster and more efficient data transmission in data center networks.

Double Density Design: The "Double Density" in the name indicates that QSFP28 DD transceivers have double the port density compared to regular QSFP28 modules. This is achieved through a more compact and efficient design, allowing data centers to maximize their network connectivity within limited physical space.

PAM4 Modulation: QSFP28 DD transceivers often utilize PAM4 (Pulse Amplitude Modulation with 4 levels) modulation. PAM4 is a more advanced modulation scheme that enables higher data rates by encoding multiple bits in each symbol. This modulation scheme is commonly used in high-speed optical communication.

Forward Error Correction (FEC): To ensure reliable data transmission, many QSFP28 DD transceivers incorporate FEC. FEC helps detect and correct errors in transmitted data, enhancing the overall reliability of the communication link.

Backward Compatibility: QSFP28 DD transceivers are designed to be backward compatible with standard QSFP28 modules. This means that data centers can upgrade their network infrastructure to higher speeds using QSFP28 DD transceivers without the need for a complete overhaul, providing a smooth transition path.

Hot-Pluggable and Hot-Swappable: Similar to other QSFP modules, QSFP28 DD transceivers are hot-pluggable and hot-swappable. This feature allows for easy installation and replacement without shutting down the entire system, contributing to reduced downtime during maintenance or upgrades.

Multi-Mode and Single-Mode Options: QSFP28 DD transceivers support both multi-mode and single-mode fiber options. This flexibility allows data centers to choose the most suitable type of optical connectivity based on their specific requirements and the distance between devices.

Advanced Monitoring and Diagnostics: QSFP28 DD transceivers often come with advanced monitoring and diagnostics features. These may include real-time temperature monitoring, power consumption reporting, and other diagnostic capabilities, providing administrators with valuable insights into the health and performance of the transceivers.

Scalability: With double the port density, QSFP28 DD transceivers contribute to higher scalability in data center networks. This is particularly important as data centers continue to grow, and there is a need for increased connectivity options without expanding physical space.

In summary, QSFP28 DD transceivers offer advanced features such as higher data rates, double port density, PAM4 modulation, backward compatibility, and advanced monitoring capabilities, making them suitable for addressing the demands of high-performance data center environments.

Additional Learning Hub Resources  

What are the common applications of QSFP28 transceivers

What are the advantages of a QSFP28 optical transceiver

What does QSFP28 stand for