The most common way to connect 100G network is to use optical transceiver. There are a variety of AOC cables, DAC cables and fiber transceivers available on the market. In order to provide a cost-effective switch connection solution, Ethernet switches need to maximize the optical module port density to provide the maximum number of channels and reduce the cost per bit transmitted. 100G switches usually use QSFP28 optical modules, which are not only compact but also have the lowest power consumption among the modules handling 100G networks.
A convenient, low-cost method of connecting 100G devices, replacing three separate components with a single assembly. Fewer parts are required, but most importantly, using AOC cable and DAC cable could eliminates the issues associated with dirty transceiver ports. Direct Attach Cables (DAC) (High Speed Cable) is suitable for 0-15m and AOC cable (Active Optical Cable) up to 70m. AOC cables provide similar performance to standalone transceivers and fibers.
Short-Distance Modules (QSFP28-SR4): Use multi-mode fiber (MMF) and MPO connectors for up to 100 meters. While MPO connectors are costly, they enable flexible cabling within data centers.
Long-Distance Modules (QSFP28-LR4/ER4/ZR4): Utilize single-mode fiber (SMF) and standard LC connectors, supporting 10–80 kilometers for inter-data center links.
Solution | Components | Distance Range | Cost/Performance | Ideal Use Case |
DAC Passive | Non-optical cable assembly | 0–3m | Lowest cost | Inside a rack |
DAC Active | Active cable assembly | 0–15m | Balanced cost/performance | Intra-rack and rack-to-rack |
AOC MM | Optical transceiver + cable | 0–70m | Higher cost than DAC | Rack-to-rack over longer spans |
MM Transceivers | SR4 + MPO cables | 0–100m | High cost | Structured cabling within DCs |
LC Transceivers | LR4/ER4/ZR4 + SM fiber | 0–10km+ | Highest performance | Long-haul inter-DC connections |
While QSFP28 excels in short to medium ranges, ultra-long-distance connections (e.g., across geographic locations) pose challenges:
Technical Limitations: For distances beyond 80km, technologies like DWDM (Dense Wavelength Division Multiplexing) are required. However, QSFP28’s PAM4 modulation demands signal amplification and dispersion compensation for distances over 5–6km, increasing complexity.
Form Factor Trade-offs: Larger modules like CFP/CFP2 support DWDM coherent technology for 1000+ km links but are impractical for high-port-density switches due to size and power consumption.
In-Data Center Connectivity: Use QSFP28 transceivers and cable assemblies for low-latency, high-density connections, minimizing per-bit costs.
Inter-Data Center Connectivity: Deploy telecom-grade DWDM systems (e.g., Sharetop OTN-2800 series) to extend 100G traffic over long distances. These platforms integrate QSFP28 outputs with transponders, amplifiers, and multiplexers in a modular, plug-and-play design, offering:
Low power consumption and scalability, Open-network architecture for flexible DWDM integration. And Cost-effective deployment via centralized management and shared infrastructure.
In 100G network, QSFP28 fiber transceiver, QSFP28 AOC Cable and QSFP28 DAC cable plays a crucial role in 100G data centers, offering a blend of compact design and low power consumption that maximizes switch port density and reduces per - bit transmission costs. For efficient connections over short distances within the data center, QSFP28 AOC and DAC cables are ideal choices, eliminating port - related issues while providing cost - effective solutions. QSFP28 transceiver could be using long distances trasmission. UnitekFiber is your reliable partner for upgrading your network, providing high qaulity 400G|800G transceivers. Contact us via sales@unitekfiber.com for a competitive price.
