AOC, DAC, AEC, and ACC Core Production Process Comparison丨C-LIGHT

In 2026, driven by the explosive growth in demand for artificial intelligence and high-performance computing, the internal data transfer speed and efficiency of data centers have become a critical bottleneck limiting the full utilization of overall computing power. In this context, four high-speed cable technologies—AOC (Active Optical Cable), DAC (Direct Attach Copper Cable), AEC (Active Electrical Cable), and ACC (Active Copper Cable)—are increasingly vital as the "data arteries" connecting servers, switches, and GPU clusters.

Core Categorization and Differentiation: Clear Definition of the Four Technical Pathways of AOC, AEC, ACC and DAC

Core Production Process Comparison: High-Speed Copper Cables and Photoelectric Integration

High-Speed Signal Copper Cables for DAC/ACC/AEC Using Physical Foaming Process, Paired with Connector Ends Featuring MSA-Compliant OSFP/QSFP/SFP Packaging and Housing Structures

High-Speed Copper Cable Production:

The high-speed copper cables used here are not ordinary wires. Their core lies in reducing signal loss during high-speed transmission. The key process is Physical Foaming Insulation. By injecting inert gases like nitrogen into the insulating material (e.g., polyolefin), a uniform, microscopic closed-cell bubble structure is formed. This structure significantly lowers the dielectric constant, reducing signal attenuation, and is fundamental for achieving single-lane rates of 56Gbps to 223Gbps (using PAM4 modulation). A complete high-speed copper cable production line also includes extruders, taping machines, stranding machines, braiding machines, and other equipment. The process involves multiple steps: solid extrusion, physical foam extrusion, taping & printing, stranding & cabling, shielding braiding, outer jacket application, and inspection.


16p copper cable	2p copper cable

Packaging Production of High-Speed Copper Cables with Standard Communication Connectors (OSFP/QSFP/SFP, etc.):

The production line for C-Light, for example, includes: PCBA firmware upload, copper cable cutting, cable core preparation, wire sequencing arrangement, automated soldering of cables to PCBA, UV protective coating for solder joints, protective block molding, connector housing assembly, anti-stress vibration testing, network analyzer testing, data traffic tester testing, product EEPROM programming, server equipment sampling inspection, coiling, adding protective sleeves, and final packaging. Unlike DAC cables, AEC and ACC cables use PCBAs integrated with Redriver or DSP+CDR Retimer chips.

Furthermore, the selected high-speed copper cables are softer, thinner, and have a smaller bend radius, making them more suitable for high-density rack deployment.


soldering of cables to PCBA	protective block molding

Core Production Process for Optical Cables (AOC): Utilizing Photoelectric Module Integration Technology

The production of AOC essentially involves permanently integrating two optical modules which reduced transmit/receive functional requirements with a segment of optical fiber. Its core processes are:

Optical Chip Packaging: Precisely packaging VCSEL (Vertical-Cavity Surface-Emitting Laser) and photodetector chips into non-airtight optical sub-assemblies.

Optical Coupling: Precisely aligning and fixing the fiber alignment prism with the optical chips to ensure the optical coupling efficiency meets AOC standards. This is a critical step affecting performance and quality.

Integrated Assembly: Performing integrated packaging of the optical fiber, the coupled optical engine, and the module housing to form a robust, non-detachable unit. This reduces connection points and improves reliability.

Final Testing: Automatically testing the encapsulated AOC cable in a data traffic/bit error rate test environment and programming EEPROM information compliant with MSA standards.