With the increasing demand for high-speed optical communications in data centers, enterprise networks, and carrier networks, 10G BiDi SFP+ optical modules have become a mainstream short-haul optical communication solution due to their single-fiber bidirectional (BiDi) transmission characteristics, fiber resource savings, and flexible deployment. In BiDi optical modules, SC (Subscriber Connector) and LC (Lucent Connector) are common fiber interface types. While they share the same functionality, they differ significantly in their physical structure, connection methods, and deployment scenarios. This article will provide an in-depth analysis of the structural characteristics and applicable scenarios of these two types of interfaces to help you make the best choice for your deployment.

1. Core Difference: Structure and Space Efficiency

(1). SC interface

Structure: Features a square snap-in interface with a large ferrule diameter (2.5 mm ceramic ferrule).

Large size: Takes up more space and is not suitable for high-density wiring environments.

Compatibility: Supports single-mode optical fiber and is widely used in low-density or early-stage networks.

(2). LC interface

Structure: It uses a miniaturized latching interface with a ferrule diameter of 1.25mm, which is only half of the SC.

Smaller size: Suitable for high-density deployment, such as data centers and areas with dense switch front panel interfaces.

Cost and process: The manufacturing process is complex, but the high-density design can reduce the overall wiring cost.

2. 10G BiDi Technical Characteristics and Interface Adaptability

(1). BiDi technology principle: magical single-fiber bidirectional transmission

BiDi technology uses wavelength division multiplexing (WDM) technology to achieve two-way communication on the same optical fiber using different wavelengths (such as 1310nm/1550nm), saving 50% of optical fiber resources.

(2). Interface performance in typical applications

1) 10G BiDi SFP+ Module: LC simplex interface, transmission distance up to 80km (1490/1550nm wavelength combination), supporting long-distance transmission scenarios such as backbone networks and metropolitan area networks.

2) 40G BiDi QSFP+ Module: LC duplex interface, using two 20Gbps channels, transmission distance 100m (OM3) to 150m (OM4), suitable for 10G-40G network upgrade.

3. Synergistic effect of interface and BiDi

-LC Interface: Highly compatible with BiDi single-fiber modules, its compact design further reduces space usage, making it the preferred choice for high-density scenarios (such as data center core switching areas).

-SC Interface: Although it supports BiDi technology, its size disadvantage limits its application in high-density environments. It is more commonly used in low-density industrial networks or single-mode long-distance transmission.

3. Core Logic of the 10G BiDi SC Interface

(1). Flexibility of low-density networks

-Simple Wiring: The plug-in lock design of the SC interface is intuitive to operate and is suitable for scenarios with low space density requirements (such as surveillance networks and branch office interconnection).

-Scalability: Although the port density is lower than LC, the modular design of the SC interface supports flexible expansion, meeting the needs of gradual upgrades in low-density networks.

(2). Typical application cases:

-Industrial Control Networks: For low-density, long-distance transmission requirements, the SC-interface BiDi module can significantly reduce fiber optic laying costs.

-Old equipment: While retaining the original SC interface equipment, BiDi technology is used to improve the transmission rate and achieve "zero-cost" cabling migration.

4. Scenario Recommendations: On-demand Selection is King

Suggestion :

-For new or upgraded high-speed network projects, BiDi SFP+ modules with LC interfaces are preferred.

-If a project has a large number of existing SC devices, consider deploying SC interface modules for compatibility and gradually transitioning to LC interfaces..

-For specific industries or environments, select the appropriate interface type based on actual needs, balancing performance and ease of operation and maintenance.

The SC and LC interfaces in 10G BiDi SFP+ optical modules each have their own advantages. When deploying a network, it's crucial to choose the most suitable interface based on the application scenario and requirements.

We hope this article will help you make the best choice in your deployment.