D-Link DEM-311GT 1000BASE-SX Multi-Mode LC SFP Transceiver

Specify the Right Gigabit Fibre Link The DEM-311GT connects a supported Gigabit SFP port to multi-mode fibre through a duplex LC interface. Its 850 nm optical design supports links up to 550 m over suitable multimode fibre, with reach dependent on the installed fibre grade. It suits switch-to-switch links and other compatible network connections where the optical path is planned as a complete system. The hot-pluggable SFP format allows a module to be installed or replaced in supported powered equipment. Match the host, far-end optical standard and fibre type before deployment. This is a two-fibre duplex connection, not a single-strand BiDi module, and the patch lead and second endpoint are selected separately. Highlights Optical Connection 1000BASE-SX Gigabit Ethernet. Duplex LC interface; 850 nm wavelength. Multi-Mode fibre; up to 550 m reach under suitable link conditions. Host Integration SFP form factor and 3.3 V host supply. Hot-pluggable in supported equipment. Confirm exact host and firmware compatibility. Link Planning Two optical paths for transmit and receive. Fibre lead and far-end module purchased separately. 5-year warranty. Key Features Match the Fibre Already Installed This module uses 50/125 µm or 62.5/125 µm multimode fibre. Multimode reach depends on the fibre core, grade and condition; a headline maximum is not a promise for every installed cable. Check the actual fibre plant rather than choosing a module by connector colour alone. A Duplex LC Optical Interface Two LC fibre paths carry transmit and receive signals. Connect them to a compatible optical endpoint with the correct polarity. A single-fibre WDM or BiDi module is a different link design and should not be substituted simply because it uses a similar LC connector. Gigabit Performance in a Small Module The SFP module supports 1000BASE-SX Gigabit Ethernet in an accepted host port. It does not upgrade an unsupported interface to a higher speed or turn every SFP+ socket into a guaranteed Gigabit port. Check the switch’s supported module and port-mode list. Service a Supported Powered Host The hot-pluggable design avoids a full switch shutdown for a supported module replacement. The affected optical link is interrupted while the module is removed. Use a maintenance window or a tested alternate path where service continuity matters. Plan the Complete Optical Path The specified maximum reach is 550 m, subject to the correct fibre and link conditions. Connector loss, splices and patch panels contribute to the optical budget. Select both endpoints and test the completed link rather than treating distance alone as a compatibility check. A Practical Component for Network Expansion The compact metal SFP housing provides a defined optical interface without dedicating an entire switch to one cable type. Label the link, protect fibre ends from contamination and follow laser-safety instructions. Keep unused connectors covered and inspect the optical path during commissioning. Summary The DEM-311GT provides a 1000BASE-SX duplex LC connection for supported Gigabit equipment. Match the multi-mode fibre, far-end optics and host configuration, then validate the installed link before relying on its rated reach. Frequently Asked Questions Which Fibre Type Does It Use?ExpandCollapse Use 50/125 µm or 62.5/125 µm multimode fibre with duplex LC connectors. Maximum reach is up to 550 m and depends on the fibre grade and optical path. Is It a Single-Fibre BiDi Module?ExpandCollapse No. It uses separate transmit and receive fibre paths through a duplex LC connector. A single-fibre BiDi pair is a different type of optical connection. Will It Work With Any SFP Port?ExpandCollapse No universal compatibility is promised. Confirm the exact switch or network adapter, firmware and supported Gigabit port mode before installation. Can It Be Replaced While the Switch Is On?ExpandCollapse Yes, in supported hot-pluggable equipment. The affected fibre link disconnects during replacement, so plan a suitable maintenance arrangement. Are Patch Leads or a Second Module Included?ExpandCollapse This offer is one transceiver. Fibre patch leads and the matching optical endpoint are selected separately for the complete link. Does a 10G SFP+ Port Make This a 10G Module?ExpandCollapse No. This is a Gigabit module. The host must explicitly support the selected Gigabit module and operating mode, even if the socket also supports faster modules. 続きを読む