SFP-10G-ER-S - Cisco 10GBase-ER SFP+ Transceiver Module

Cisco SFP-10G-ER-S — 10GBASE-ER S-Class SFP+ Transceiver, 1550nm, 40km What it is SFP-10G-ER-S is a Cisco 10 Gigabit Ethernet SFP+ optical transceiver designed for long-distance connections over single-mode fiber (SMF). It operates at approximately 1550nm and supports 10GbE links of up to 40 kilometers over standard G.652 single-mode fiber, making it well suited to building-to-building, campus backbone, metro, and long-distance network links. Why buyers pick SFP-10G-ER-S (plain English) Up to 40km reach: Much longer distance than SR or LR optics, making it suitable for connecting sites across campuses or metropolitan areas. Standard single-mode fiber: Works over widely deployed G.652 SMF, so it integrates easily into existing long-distance fiber infrastructure. Compact SFP+ format: Fits directly into compatible Cisco 10G SFP+ ports without requiring a separate media converter. LC fiber connector: Uses the familiar duplex LC interface common across enterprise fiber networks. S-Class value: The S-Class version is intended for straightforward Ethernet applications where the additional protocol support of some full-feature Cisco optics is not required. 60-second spec box (SFP-10G-ER-S) Ethernet standard 10GBASE-ER 10 Gigabit Ethernet S-Class transceiver Fiber type Single-mode fiber (SMF) Designed for G.652 fiber Maximum reach Up to 40 km Actual reach depends on fiber loss, connectors, splices, and overall optical budget Wavelength Nominal 1550nm Operating wavelength range approximately 1530–1565nm Connector Duplex LC Two-fiber transmit / receive connection Form factor SFP+ Hot-swappable Plugs into compatible Cisco SFP+ interfaces Optical characteristics Transmit power: approximately -4.7 to +4.0 dBm Receive sensitivity down to approximately -15.8 dBm Suitable for long-reach 10GbE links Compatibility Designed for supported Cisco switches, routers, and other platforms with compatible 10G SFP+ ports Platform compatibility should be checked before deployment Protocol support 10 Gigabit Ethernet The SFP-10G-ER-S does not support FCoE Where it fits (and when to choose something else) Perfect for: Building-to-building fiber links Campus backbone connections Metro-area Ethernet links Data-center interconnects Long-distance 10GbE connections Sites separated by several kilometers of single-mode fiber Choose something else if: You only need short multimode links → use SFP-10G-SR-S You need up to 10 km over single-mode fiber → use SFP-10G-LR-S You need around 80 km → consider SFP-10G-ZR-S You need industrial-temperature operation → consider SFP-10G-ER-I You require FCoE support → use an appropriate non-S-Class optic supported by your platform TL;DR SFP-10G-ER-S is a Cisco 10GBASE-ER SFP+ transceiver providing 10Gbps connectivity over single-mode fiber at 1550nm for distances up to 40 km — ideal for long-distance campus, metro, and inter-building Ethernet links.