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CISCO QSFP-40G-SR4-S= QSFP+ Module, 40GBASE-SR4, 4 lanes, 850 nm MMF
- Hot-swappable input / output device that plugs into a 40 Gigabit Ethernet Cisco QSFP port
- Interoperable with other IEEE-compliant 40GBASE interfaces where applicable
- Certified and tested on Cisco QSFP 40G ports for superior performance, quality, and reliability
- High-speed electrical interface compliant to the IEEE 802.3ba standard
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40GBASE-SR4 QSFP Trnscvr Module, MPO Conn, Enterprise-Class
Warranty & Returns
Warranty, Returns, And Additional Information
Warranty
- Limited Warranty period (parts): 1 year
- Limited Warranty period (labor): 1 year
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Return Policies
- Return for refund until: January 31, 2027
- Return for replacement until: January 31, 2027
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Manufacturer Contact Info
- Manufacturer Product Page
- Manufacturer Website
- Support Phone: 1-800-553-6387
- Support Website
- View other products from Cisco Systems, Inc.
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The Cisco QSFP-40G-SR4-S= is a hot-swappable 40GBASE-SR4 QSFP+ multimode-fiber transceiver for Cisco 40 Gigabit Ethernet QSFP ports, suited to network teams connecting compatible equipment over MTP/MPO fiber links up to 492 ft.
Recommended For
- Network teams connecting supported Cisco QSFP+ ports over short-reach multimode fiber for 40GbE links, with a maximum reach of 100 m on OM3 or 150 m on OM4/OM5.
- Data-center and enterprise network operators whose link endpoints have MPO/MTP multimode-fiber connections and need a parallel-fiber 40G link.
- Cisco network technicians replacing or adding optics in a supported 40G QSFP port who want a hot-swappable module identified for Cisco platforms.
Real-World Use Scenarios
- Connecting two Cisco switches in a data center over MPO/MTP multimode fiber gives the network a 40G link, with supported reach up to 100 m on OM3 or 150 m on OM4/OM5.
- Adding a short-reach 40G connection between nearby network racks is a practical fit when both ends have compatible QSFP ports and the cable route uses parallel multimode fiber; it avoids using a long-reach single-mode optic for this link.
- Upgrading a short-distance switch-to-switch or aggregation link to 40G can provide more capacity for traffic moving between network segments, provided the switches support this Cisco optic and the fiber plant meets the reach requirements.
- Replacing or installing the optic in a supported Cisco QSFP port can be done as a hot-swap, which helps during maintenance when the platform permits the module to be changed without powering down the device.
- If a network redesign needs one 40G port split into four 10G links, this S-Class model is not the right choice: it does not support 4x10G breakout, so a different compatible optic is needed.
Spec Summary
| Attribute | Value |
|---|---|
| Best For | 40GbE network-switch links over multimode fiber using a Cisco QSFP 40G port |
| Optical Interface And Reach | 40GBASE-SR4 over multimode fiber through an MTP/MPO port, with an 840–860 nm wavelength and a maximum distance of 492 ft |
| Connectivity And Compatibility | Hot-swappable QSFP+ transceiver for Cisco QSFP 40G ports; interoperable with IEEE-compliant 40GBASE interfaces where applicable, with Cisco quality identification for supported optics |
| Standards And Compliance | Complies with FCC CFR21 Part 1040, GR-326-CORE, GR-20-CORE, GR-1435-CORE, MSA SFF-8431, MSA SFF-8436, IEC 60825-1 Class 1, CE, and RoHS |
| Power And Operating Conditions | 1.5 W power requirement; operating temperature range of 32–158°F |
| Dimensions And Weight | 0.50 × 0.70 × 2.90 in; 0.22 lb |
| Model Identifiers | Cisco QSFP-40G-SR4-S= |