2×200G InfiniBand Active Optical Splitter Cable: Advantages and Applications

In high-performance computing, servers often use an eight-GPU setup and eight 200G InfiniBand cards for network communication and bandwidth. As server clusters grow, the cost of high-speed, low-latency, lossless network gear rises sharply. When server nodes exceed 100, the network shifts from a two-layer to a three-layer FAT TREE, increasing network input cost.

The 2×200G InfiniBand active optical splitter cable enhances port connections between spine switches and leaf switches, significantly boosting network expansion capability.

Understanding 2×200G InfiniBand Active Optical Splitter Cable

2×200G InfiniBand active optical splitter cable, specifically the QSFP-2Q200G-2QAOxx cable offered by FS, is an InfiniBand AOC breakout cable based on QSFP56 VCSEL technology. It enables 2x 200Gb/s data transmission and complies with QSFP56 MSA and IEEE 802.3 standards. In addition, the 2×200G IB active optical breakout cable enables higher port bandwidth, density, and configurability at a low cost, and reduced power requirements in data centers.

Application of 2×200G InfiniBand Active Optical Splitter Cable

The primary application of the 2×200G InfiniBand active optical splitter cable is to connect 200G leaf switches and spine switches in a Fat Tree topology, facilitating cross-connection functionality. This enables the ports of InfiniBand HDR switches to operate 2×200G to 2×200G link. The link simplifies patching and offers a cost-effective way for short links, which provides power-efficient connectivity for data center interconnects, as illustrated in the diagram below.

Advantages of the 2×200G InfiniBand Active Optical Splitter Cable

The 2×200G InfiniBand AOC breakout cable offers numerous advantages and applications in large-scale server clusters. By maximizing port access capacity, expanding network scalability, and reducing costs, this cable enhances the networking capabilities of InfiniBand switches, making it a valuable solution for high-performance computing and other large-scale computing environments.

Increased Port Access Capacity

A single 2x200G InfiniBand AOC breakout cable only requires 4 ports to fully interconnect between two spine switches and two leaf switches. Its maximum access capacity is doubled compared to 200G InfiniBand HDR AOC cables. To achieve the same interconnection with 100G InfiniBand HDR AOC cables, 4 such cables would be needed. However, four 100G InfiniBand HDR AOC cables would occupy 8 device ports, limiting network scalability.

As the following picture shows, using 200G InfiniBand HDR AOC cables and InfiniBand HDR switches, a 2-layer Fat Tree network with 20 spine switches and 40 leaf switches can access up to 800 200G ports, meeting the needs of 100 servers.

In contrast, using 2×200G InfiniBand AOC breakout cables and InfiniBand HDR switches in the same Fat Tree architecture doubles the maximum access capacity to 1600 200G ports, supporting the needs of 200 eight-GPU servers.

Expanded Network Scalability

As shown in the figure above, the 2×200G InfiniBand active optical breakout cable enables the first leaf switch to connect with 2 spine switches using just one port, doubling network scalability. In a network setup that meets the requirements for 200 servers with eight GPU cards each, using 200G InfiniBand HDR AOC cables would form a three-tier Fat Tree architecture, requiring more switch devices and 200G InfiniBand AOC cables, as shown in the following figure.

Cost Reduction

Compared to networking with 200G InfiniBand HDR AOC cables, implementing the 2×200G InfiniBand active optical breakout cable significantly reduces the number of required devices. Building a network with 2×200G InfiniBand active optical breakout cables, the number of InfiniBand switches decreases from 200 to 120, resulting in substantial cost savings.

Conclusion 

The 2×200G InfiniBand active optical splitter cable is an efficient solution for high-performance computing. FS's 2×200G InfiniBand cable offers a cost-effective alternative by doubling port capacity, improving network scalability, and reducing the number of switches needed, thus lowering overall costs. This makes the 2×200G InfiniBand HDR AOC breakout cable valuable for enhancing InfiniBand switch networking in large-scale server clusters.