What is the interface of the optical module called

Optical modules have two primary interfaces: an electrical interface for system connection and an optical interface for fiber connection.Electrical InterfaceThe electrical interface connects the optical module to the internal system, such as a switch, router, or server. It transmits electrical signals to the module for conversion into optical signals and receives electrical signals converted from incoming optical signals. Early optical modules used analog NRZ electrical interfaces, while modern modules typically use digital interfaces like the Common Electrical Interface (CEI) defined by the Optical Internetworking Forum (OIF) and standards from IEEE 802.3 for Ethernet applications. These interfaces may be retimed or non-retimed, depending on power and performance requirements, and are often specified by multi-source agreements (MSAs) to ensure interoperability between vendors.Optical InterfaceThe optical interface connects the module to the external fiber optic network. It includes the fiber optic connector and the optical transceiver port, which can support single-mode or multi-mode fibers. Common optical connector types include LC, SC, and FC, each with specific characteristics suitable for different applications, such as data center LANs or long-distance WANs. The optical interface is responsible for transmitting modulated light signals from the Transmitter Optical Sub-Assembly (TOSA) and receiving light signals via the Receiver Optical Sub-Assembly (ROSA), which are then converted back into electrical signals.Additional FeaturesMany optical modules also include Digital Diagnostic Monitoring (DDM) interfaces, which allow real-time monitoring of parameters like transmitted and received optical power, temperature, and voltage. This interface ensures proper operation and helps maintain network reliability.SummaryIn essence, an optical module bridges the electrical and optical domains through its electrical interface (system connection) and optical interface (fiber connection), with additional monitoring interfaces like DDM enhancing performance and reliability. Common module types include SFP, GBIC, XFP, and XENPAK, each supporting specific interface standards and connector types to meet various network requirements .