The Cisco QSFP‑40G‑LR4‑S is a 40 Gbps single‑mode fiber transceiver (10 km reach, duplex‑LC) — ideal for long‑distance, high‑bandwidth data‑center or enterprise interconnects.

Feature

Specification

Model / Part Number

Cisco QSFP‑40G‑LR4‑S

Type

40GBASE‑LR4 QSFP+ Optical Transceiver

Media Type

Single‑Mode Fiber (SMF, G.652)

Wavelength

1310 nm (CWDM: 1271 / 1291 / 1311 / 1331 nm per lane)

Connector

Duplex LC

Data Rate

40 Gbps (aggregate) — 4 × 10.3125 Gbps lanes

Maximum Reach

Up to 10 km over SMF

Transmitter Type

4‑lane CWDM DML laser

Receiver Type

PIN photodiode

Transmit Power (per lane)

–7.0 to +2.3 dBm

Receiver Sensitivity (per lane)

–13.7 dBm (min)

Power Consumption

~3.5 W

Compliance / Standards

IEEE 802.3ba (40GBASE‑LR4), QSFP+ MSA, SFF‑8436, RoHS

Operating Temperature

0 °C to 70 °C (standard)

Hot‑Swappable

Yes