Comparison of connection costs between network cables and optical fibers

Comparison of connection costs between network cables and optical fibers
The comparison of connection costs between network cables and optical fibers cannot be generalized. It highly depends on the transmission distance and application scenarios. In actual construction such as in data centers, there is a significant "cost scissors gap" effect between the two. The following is a detailed comparative analysis:

1. Short-distance scenarios (within 10 meters): Network cables/copper cables have an overwhelming cost advantage
In the extremely short-distance interconnection between servers and access layer switches (ToR), the cost of copper cables (such as network cables, DAC high-speed copper cables) is much lower than the optical interconnection solution.
Material and equipment costs are low: The cost of a passive copper cable is only 1/10 of the cost of a high-speed optical module with the same rate. For example, in a 72-GPU cabinet solution, using copper cables can reduce the overall cost by more than 80% compared to the optical interconnection solution.
Construction and termination thresholds are low: The production of network cable connectors and the plugging and unplugging of jumpers is relatively simple, and no expensive fusion splicing equipment is required. While optical fibers require professional fusion splicing machines, end-face cleaning tools, and OTDR testers, and are extremely sensitive to end-face contamination and bending radius, the construction labor cost is higher.
2. Medium-long distance scenarios (over 10 meters): The full life cycle cost of optical fibers is more favorable
When the transmission distance is extended, the cost equation will rapidly reverse.
Material cost sensitivity to distance: When the distance exceeds 7-10 meters, the cost of copper cables will significantly increase due to the thicker wire diameter, increased material, and signal attenuation; while the cost of optical fibers and optical modules is not sensitive to distance. In long-distance scenarios of over 100 meters, the cost benefit of optical fibers in the full life cycle will completely surpass that of copper cables.
Laying and construction costs: According to industry estimates, the laying cost per end point of optical fibers (including materials, termination, and testing) is typically between $350 and $2,000, significantly higher than the $150 to $700 of copper cables. Although optical fibers are more expensive for a single installation, they support kilometer-level transmission and avoid the expensive intermediate equipment required for long-distance copper cable use.
3. Core component and consumable cost differences
As the network upgrades to 400G, 800G, and even higher bandwidths, the cost of core components in the optical fiber ecosystem is rapidly increasing:
High-density connectors (MPO): The demand for MPO connectors in AI data centers has surged, and they are evolving towards higher core counts (such as 32-core, 64-core). The unit price of 64-core MPO can be more than 10 times that of 64-core. Combined with the price fluctuations of optical fibers, the overall cost of optical fiber links is pushed up.
Optical modules and CPO switches: Coherent optical modules supporting high-speed interfaces have a relatively high unit price. Taking the latest CPO (co-encapsulated optical) switch as an example, the BOM (bill of materials) total cost of a single device can reach approximately $70,000, with the optical engine and fiber multiplexer box being the largest cost items.
4. Operation and hidden cost comparison
Network cables: The structure is simple, and the passive design makes the failure rate extremely low, and troubleshooting is intuitive, with almost negligible operation and maintenance costs.
Optical fibers: There is a certain annual failure rate (in the range of a few thousandths) for plug-in optical modules. In a super-large-scale cluster with thousands of optical modules, dozens of modules will naturally fail each year. The fault troubleshooting of optical links takes longer, and a single troubleshooting may take several hours, increasing the operation and maintenance time cost and cluster availability risk.
Summary and recommendations:
For interconnection within cabinets within 10 meters, priority should be given to network cables or passive copper cables, with extremely high cost-effectiveness; while in cabinet interconnection, cross-floor backbone network, or long-distance data center interconnection (DCI) scenarios, although the initial equipment and construction costs of optical fibers are higher, their advantages in bandwidth limit, transmission distance, and long-term operation and maintenance make them an indispensable and more economically beneficial choice.