Views: 599 Author: Addams Publish Time: 2026-05-11 Origin: Site
In some network scenarios, as services expand and develop, the demand for bandwidth grows exponentially, but network infrastructure development cannot keep up with this growth. Infrastructure construction, especially the laying of fiber optic resources, is time-consuming, labor-intensive, and resource-intensive. Therefore, for a long time, networks will face the problem of fiber optic resource shortages, which have become core bottlenecks restricting further increases in network bandwidth. BiDi (Bi-Directional, single-fiber bidirectional) optical modules were developed precisely to solve this problem.
Traditional classic dual-fiber optical modules use a full-duplex LC interface, requiring two fibers to handle signal transmission and reception respectively. This occupies two fibers, which is wasteful in the current context of fiber optic resource scarcity. This has driven engineers to seek more efficient transmission methods that utilize fiber optic resources. This is where WDM technology came into focus.
BiDi optical modules are a classic example of wavelength division multiplexing (WDM) technology. They transmit and receive two optical signals of different wavelengths over a single optical fiber, enabling simultaneous bidirectional data transmission. This means the amount of fiber used is directly halved, significantly alleviating fiber resource constraints without changing the transmission bandwidth.
100G BiDi optical modules use a simplex LC optical interface, allowing signal transmission and reception on a single fiber. Therefore, 100G BiDi places higher demands on signal processing. Some models have additional DSP chips to assist in signal processing, resulting in higher costs, higher power consumption, and poorer signal quality—two to three orders of magnitude lower than 100G dual-fiber modules.
100G dual-fiber optical modules use a full-duplex LC optical interface, requiring two optical fibers to handle signal transmission and reception respectively. This results in lower signal processing requirements and, compared to 100G BIDI optical modules, lower cost, lower power consumption, and superior signal quality. Typically, zero-error transmission can be achieved within the specified transmission distance.
There are significant differences between 100G BIDI optical modules and 100G dual-fiber optical modules. Therefore, when selecting a product, it is necessary to choose the appropriate model based on the specific construction budget and environment. In environments with limited budgets and abundant fiber resources, 100G dual-fiber optical modules can be chosen, offering lower construction costs and higher signal quality. In environments with ample budgets but limited fiber resources, 100G BIDI optical modules can be selected, providing more transmission bandwidth and supporting more services. In environments with both limited fiber resources and a tight budget, a hybrid transmission approach combining 100G BIDI and 100G dual-fiber modules can be used, offering the low-cost advantages of 100G dual-fiber modules and the fiber-saving advantages of 100G BIDI modules, providing as much service access as possible within a limited budget.
The use of 100G BIDI optical modules differs significantly from traditional 100G dual-fiber optical modules. Therefore, in field applications, engineers may encounter usage problems due to unfamiliarity with 100G BIDI optical modules, slowing down project progress. Today, we will discuss some common problems in detail and provide solutions.
100G BiDi optical modules require cross-pairing of wavelengths at both ends. Incorrect insertion at either end will prevent the establishment of a communication link. Mismatched wavelengths will cause the optical module to fail to receive optical signals, resulting in link interruption. We can address this by standardizing A/B end labeling before deployment (e.g., using red labels for A and blue labels for B) and establishing a link information database using these labels to record the serial number (SN), wavelength, and specific location of the modules at both ends of each link, providing assistance for later maintenance.
Due to the poor signal quality of 100G BiDi optical modules, forward error correction (FEC) is necessary in practical use. However, different manufacturers' equipment uses different default FEC modes. Different FEC modes can cause DDM information to be normal, but the link to go down. The FEC at both ends must be configured to FEC74 to restore the connection. Before rack installation, we must confirm the FEC requirements (FEC type, FEC mode switch, whether it must be enabled) from the equipment's user manual and ensure consistent configuration on both sides of the switch to avoid FEC problems.
100G BiDi optical modules use simplex LC connectors, not the full-duplex LC connectors of 100G dual-fiber optical modules. Using the wrong fiber connector will cause hardware incompatibility. Therefore, it is essential to confirm the type of fiber purchased before installation.
100G BiDi optical modules offer a highly attractive solution in high-density scenarios where fiber resources are scarce, but they also have higher requirements for deployment specifications. During use, different solutions need to be flexibly selected based on the site environment, and different product combinations are needed to establish a stable and efficient network. YXFiber, a professional one-stop network solution provider.
