High-speed connectivity is the backbone of data centers. While optical transceivers are essential for long distances, Direct Attach Copper (DAC) cables remain the gold standard for short-reach, intra-rack connections. They offer the most cost-effective, lowest-latency, and lowest-power consumption solution available. This article explores what 800G OSFP DAC is, how it works, and why it is becoming a critical component in modern AI data center architectures.
What Is 800G OSFP DAC Cable?
800G OSFP DAC cable is a high-speed passive copper interconnect designed for ultra-short-distance data transmission between switches, servers, and GPUs. Built on the OSFP form factor, it supports 8 lanes of 112G PAM4 signaling, delivering a total bandwidth of 800Gbps.
Unlike optical solutions, DAC cables transmit electrical signals directly over twinax copper, which eliminates the need for:
- Optical lasers
- Digital signal processing (DSP)
- Additional power consumption
As a result, 800G DAC cables are the most energy-efficient and cost-effective solution for intra-rack connectivity.
Why 800G DAC Cable Is Ideal for AI Data Centers?
AI clusters, GPU fabrics, and HPC environments rely heavily on short-reach, high-bandwidth interconnects. In these scenarios, 800G DAC cables deliver clear advantages.
For links within the same rack, DAC cables:
- Reduce hardware costs by up to 80% compared to optical transceivers
- Provide ultra-low latency, critical for GPU-to-GPU communication
- Consume zero power, improving overall data center PUE
- Simplify deployment by removing optical components
Because AI workloads are extremely sensitive to latency and cost efficiency, 800G DAC cables have become the default choice for intra-rack connections in AI infrastructure.
800G DAC vs AOC vs Optical Transceivers
Choosing the right interconnect depends largely on distance, cost, and architecture design.
For distances under 3 meters, DAC cables provide the best balance of performance and cost. They require no power, introduce minimal latency, and are significantly cheaper than optical alternatives.
Active Optical Cables (AOCs) are better suited for medium-range connections where flexibility is needed but cost is still a concern.
Optical transceivers, on the other hand, remain essential for long-distance transmission but come with higher power consumption and cost due to integrated lasers and DSP components.
In short, DAC is the preferred solution for short-reach, high-density AI deployments.
AICPLIGHT 800G OSFP DAC Product Portfolio
AICPLIGHT provides a complete range of 800G OSFP DAC solutions, including straight-through and breakout configurations to accommodate various network topologies.
800G OSFP to OSFP Passive DAC
AICPLIGHT 800G OSFP Finned Top Passive DAC enables direct 800G connectivity between switches. With lengths typically ranging from 0.5m to 2.5m, it is ideal for top-of-rack (ToR) and spine switch interconnections within the same rack. The finned top design enhances heat dissipation, ensuring stable operation in high-power 800G systems.
Figure 1: A product diagram illustrating a direct interconnection between two Cisco 8122-64EHF-O switches using a single 800G OSFP to OSFP Passive DAC.
800G OSFP to 2×400G OSFP Breakout DAC
AICPLIGHT 800G OSFP Finned Top to 2 x 400G OSFP Flat Top Breakout DAC allows a single 800G port to connect to two 400G endpoints, enabling flexible network scaling and efficient port utilization. It is particularly useful in mixed-speed environments where 800G core switches need to interface with existing 400G infrastructure.
Figure 2: Connectivity diagram of an AICPLIGHT 800G OSFP to 2x400G OSFP breakout solution linking a high-capacity Cisco switch to NVIDIA H100 server nodes.
800G OSFP to 2×400G QSFP112 Breakout DAC
AICPLIGHT 800G OSFP Finned Top to 2 x 400G QSFP112 Breakout DAC is designed for cross-platform compatibility. This solution bridges OSFP and QSFP112 ecosystems. It allows seamless integration between next-generation 800G switches and 400G NICs or servers. This makes it a practical choice for phased upgrades in AI and cloud data centers.
Figure 3: This diagram illustrates an 800G OSFP to 2x 400G QSFP112 passive copper breakout cable connecting a Cisco 8122-64EHF-O switch to an H100 server via MCX715105AS-WEAT network adapters.
800G OSFP to 4 x 200G OSFP Breakout DAC
AICPLIGHT 800G OSFP Finned Top to 4 x 200G OSFP Finned Top Breakout DAC enables a single 800G OSFP switch port to be split into four independent 200G OSFP channels, facilitating highly efficient 1-to-4 connectivity. It provides a seamless pathway for aggregating traffic from multiple 200G compute nodes or storage units into a high-speed 800G core, all while maintaining the ultra-low latency and zero power consumption inherent to passive copper solutions.
Figure 4: An application diagram showcasing an 800G OSFP to 4 x 200G OSFP passive copper breakout cable connecting a Cisco 8122-64EHF-O switch to an H100 server via four MCX75310AAS-HEAT network adapters.
800G OSFP to 4 x 200G QSFP112 Breakout DAC
AICPLIGHT 800G OSFP Finned Top to 4 x 200G QSFP112 Breakout DAC is a high-performance passive copper solution designed for maximum port density and cross-standard integration. This 1-to-4 breakout cable splits a single 800G OSFP port into four discrete 200G QSFP112 channels, enabling the seamless connection of high-capacity 800G switches to a wide range of 200G servers, storage arrays, or network nodes. It provides network architects with the flexibility to scale their infrastructure from 200G to 800G without replacing existing QSFP-based equipment, offering a sustainable and cost-effective pathway to massive bandwidth expansion.
Figure 5: An application diagram showing an 800G OSFP to 4 x 200G QSFP112 passive copper breakout cable linking a Cisco 8122-64EHF-O switch to an H100 server via MCX755106AS-HEAT network adapters.
Conclusion
As AI infrastructure continues to evolve toward higher bandwidth and density, 800G OSFP DAC cables play a critical role in optimizing short-reach connectivity. By combining ultra-low latency, zero power consumption, and significant cost savings, AICPLIGHT's 800G DAC solutions provide a reliable and scalable foundation for modern data centers.
If you are planning to deploy or upgrade an AI cluster, choosing the right interconnect strategy starts with selecting the most efficient solution for each distance tier—and for short-range links, DAC remains the clear winner.
Frequently Asked Questions (FAQ)
Q: What is the maximum distance of 800G DAC cables?
A: Most passive 800G DAC cables support distances up to 2–3 meters, depending on signal integrity and system compatibility.
Q: Can 800G DAC support breakout configurations?
A: Yes. 800G DAC cables can be split into 2×400G or 4×200G connections, allowing flexible network design and efficient port utilization.
Q: Is DAC better than AOC for AI workloads?
A: For short distances, DAC is generally better due to lower latency, zero power consumption, and lower cost. AOC is preferred only when longer reach is required.
Q: Do DAC cables require power?
A: No. Passive DAC cables do not consume power, making them highly energy-efficient.
Article Source: 800G OSFP DAC Cable: Low-Cost Solution for AI Data Center Short-Reach Links
