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Optical Gigabit Ethernet is Ethernet running at 1,000 Mb/s over fiber-optic cable. It uses an optical physical layer—commonly 1000BASE-SX or 1000BASE-LX—while retaining the Ethernet frame format. The right optic depends on the fiber, link distance, and equipment at both ends.
What “optical Gigabit Ethernet” means
“Gigabit” refers to the link speed: 1,000 megabits per second (1 Gb/s). “Optical” means the physical link carries signals over fiber rather than copper. IEEE 802.3 specifies Ethernet across multiple speeds and media, using a common media access control (MAC) layer with physical layers (PHYs) suited to particular media. Its 1,000 Mb/s PHY family includes 1000BASE-SX and 1000BASE-LX, as well as copper 1000BASE-T. IEEE 802.3-2022 overview
Optical Gigabit Ethernet is therefore a choice of physical medium and PHY, not a separate Ethernet frame format. The Ethernet link still needs compatible equipment at both endpoints; the fiber and optics determine how the signal travels between them.
1000BASE-SX vs. 1000BASE-LX
SX and LX identify different optical PHY options. In general, SX is the short-wavelength choice associated with multimode fiber, while LX uses longer-wavelength optics and is commonly used with single-mode fiber. Particular transceivers may support more than one fiber type, but their specified limits still apply.
#1 Best Overall
- 4PCS Gigabit SFP to RJ45 Copper Module 10/100/1000M Auto-Negotiation;Data Rate:1.25Gb/s, Interface:RJ45 connector; Reach:up to 100M transmission over CAT.5e Cable Type.
- Widely Used in fiber switches,routers,NIC,server or other fiber optic equipments with 1Gb SFP ports.★Compatible with MSA compliant equipment Cisco Meraki,Ubiquiti,D-Link, Supermicro,TP-Link,Broadcom,Linksys and Huawei,Mikrotik,Netgear,Supermicro Other Open Switches.
- Connects a network switch SFP to RJ45 Gigabit Ethernet network for Network Attached Storage (NAS), Storage Area Network (SAN), and High Performance Computing (HPC) applications Low power consumption and low EMI emission design SFP RJ45 module; Hot-pluggable with advanced ESD protection.
- Easy to use & Durable: Plug and play, hot-pluggable. Rotate the ring latch down at 90 degree angle to unlock, then pulling transceiver out from switch. Less than 1.05W power dissipation and heat-conducting gasket provide superior heat dissipation function.
- GESD is a professional manufacturer and accept customized orders. If you are not sure about the compatibility of your device, please feel free to contact us for customized SKU to meet your needs(We offer many compatible options).★After-sales Service:30-day free return,3-year warranty,lifetime technology support.We produce high quality transceivers,every transceiver has been tested for 28 steps before shipping.
| Factor | 1000BASE-SX | 1000BASE-LX |
|---|---|---|
| Wavelength information | Cisco’s overview describes SX at 850 nm. Cisco GLC-SX-MM product page | The Fiber Optics Tech Consortium gives an operating range of 1270–1355 nm for LX. Fiber Optics Tech Consortium 1000BASE-X overview |
| Typical fiber | Multimode fiber (MMF). | Single-mode fiber (SMF) is common; some transceivers also support multimode fiber within specified limits. |
| Published example reach | Cisco specifies up to 550 m on ordinary multimode fiber for its GLC-SX-MM. A separate Cisco data sheet specifies up to 550 m on legacy 50 μm multimode fiber and up to 220 m on 62.5 μm FDDI-grade multimode fiber for an SX SFP. GLC-SX-MM product page Cisco Gigabit Ethernet SFP data sheet | Cisco specifies up to 10 km on standard single-mode fiber and up to 550 m on multimode fiber for the LX/LH SFP covered in its data sheet. Cisco Gigabit Ethernet SFP data sheet |
These are vendor or consortium specifications and planning figures, not universal distance guarantees. Fiber grade, connectors, patching, optic model, and the link budget affect the supported reach. The consortium’s planning information also specifies assumptions and ranges by fiber class. Check the documentation for the exact transceiver and fiber path rather than relying on “SX” or “LX” alone.
How to choose a Gigabit fiber transceiver
An SFP is a pluggable transceiver that connects a compatible Gigabit Ethernet port or slot to a fiber-optic network. Cisco describes its SFP as a hot-swappable input/output device. Cisco GLC-SX-MM product page Selecting one requires checking both ends of the link and the installed fiber, not just the desired speed.
Rank #2
- Data Rate: 10/100/1000Mbps Auto-Negotiation
- SFP to RJ45: Converts SFP optical ports to RJ45 ports, enabling seamless fiber-to-traditional Ethernet connectivity
- RJ-45 Copper：This 1G SFP to RJ45 module supports link to Cat5e/Cat6/Cat7 cables, up to 100m
- Plug and Play: This Gigabit SFP copper module supports Hot-pluggable SFP MSA, no need to shut down the network or device reboot
- Wide Compatibility: This 1000BASE-T transceiver is compatible with Cisco SFP-GE-T / GLC-T, Ubiquiti UniFi UF-RJ45-1G / UACC-CM-RJ45-1G, Mikrotik S-RJ01, Netgear AGM734, D-Link, Supermicro, Linksys, Zyxel, and other open SFP switches. (Note: Not compatible with HP/HPE switches)
- Check the host equipment. Look up the switch or network card’s supported SFP list and confirm the port supports the module type. Compatibility for a specific device cannot be determined without its model and documentation.
- Match the PHY at both ends. Choose compatible SX or LX optics for the two endpoints; do not assume different optic types will form a supported link.
- Match the fiber and connector. Confirm whether the cable plant is multimode or single-mode, and verify the connector and wavelength requirements for the selected modules.
- Verify the complete link distance. Compare the actual route, including patching and connectors, with the transceiver’s stated reach and link-budget requirements. Apply the relevant fiber-grade limits rather than a generic maximum.
When the label alone is not enough
Two products labeled for the same Gigabit optical PHY may not have identical reach or host compatibility. For example, the cited Cisco SX specifications distinguish ordinary multimode fiber from legacy 50 μm and 62.5 μm fiber, while the cited LX/LH specification gives separate single-mode and multimode limits. Those figures apply to the particular documented products; they should not be transferred to another vendor’s optic without checking its specifications.
Use the equipment vendor’s compatibility information and the selected transceiver’s data sheet to validate a proposed link. If the fiber type, route length, connector details, or port support is unknown, those are the facts to identify before selecting an SFP.
Quick Recap
Best Value
- Data Rate: 10G
- Interface: RJ-45
- Cable Type: CAT.6a/CAT7
- Reach: up to 30 meters (PLEASE NOTE this 10GBase-T SFP+ transceiver may get hot when it's working, because it's built with the latest IC: Marvell AQR113C. We suggest to use this product in places where the ambient temperature is below 50°C.)
- Wide Compatibility - for Cisco, Fortinet, Netgear, D-Link, TP-Link, Linksys, Broadcom, Edge-core, EMC, F5, Meraki, Norkia, QTC, Supermicro, and Other Open Switches. (Not compatible with HP-ProCurve, HP-H3C, HP-Aruba, Intel, Arista, Mellanox, Dell Force10, Extreme, Brocade, Juniper). For Ubiquiti devices, we recommend this transceiver: ASIN B094N9YKN9.
Rank #4
- 10g SFP+ Copper: Fully Compatible with 100+ Vendors, such as: Netgear, D-Link, Supermicro, Mikrotik, Fortinet and Other Open 10gb switch.
- Data Rate: 10gbs, Interface: copper RJ-45 connector, Low power consumption ≤2.5w, 10GBase-T module for CAT6A/CAT7/CAT8 cable. Supports 1000Mbps rate for using Cat 5e cable or better. (30 meters via 10Gbps, 50 meters via 5Gbps and 2.5Gbps, 100 meters via 1000Mbps.)
- Easy to Use: Plug and play, hot-pluggable. Rotate the ring latch down at 90 degree angle to unlock, then pulling transceiver out from switch. Widely used in fiber switches, pcie ethernet adapter, router, NIC, server or other fiber optic equipments with 10Gb SFP+ ports.
- QSFPTEK Guarantee: All of products are manufactured under strict quality control system, every module has been tested one by one on different switches before shipping, to ensure compatibility with different brand of switch.
- After-sales Service: 30-day free return, 1-year warranty, lifetime technology support. QSFPTEK is a manufacturer of transceiver. Accept OEM, ODM, any request please contact us anytime, we will reply within 24 hours.
Rank #3
- Gigabit SFP to RJ45 Module: Add a standard RJ45 copper Ethernet connection to a compatible network switch, router, server, or NIC with this 1000BASE-T SFP transceiver. Supports Gigabit Ethernet with an SFP signaling rate up to 1.25Gbps.
- Up to 100m over Cat5e / Cat6 Ethernet Cable: This SFP to Ethernet module supports 10/100/1000Mbps Ethernet over Cat5e, Cat6, or higher twisted-pair cable at distances up to 100m. Available speed depends on the host interface and its auto-negotiation capabilities.
- Universal MSA Compatibility: This SFP to Ethernet adapter is compatible with MSA-compliant equipment from Cisco, HPE Aruba, Ubiquiti, TP-Link, Netgear, MikroTik, Intel, D-Link, and Supermicro. Its MSA-compliant serial identification allows compatible host equipment to read module information from the built-in EEPROM. Not compatible with proprietary vendor-locked SFP ports.
- Hot-Swappable Metal Design: Install or remove the RJ45 SFP module without powering down compatible host equipment. The shielded metal enclosure helps reduce electromagnetic interference, while power consumption below 1.2W supports efficient network deployment.
- SFP and SFP+ Port Support: Designed for compatible SFP ports and SFP+ ports that support operation at 1Gbps. This SFP module to RJ45 copper transceiver complies with SFP MSA INF-8074i and IEEE 802.3ab for enterprise, data-center, office, and lab networks.
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