Juniper 25GBASE-SR SFP28 Transceiver — 100m Multi-Mode Fiber

The Juniper 740-068639 is a 25GBASE-SR SFP28 optical transceiver delivering 25GbE over multi-mode fiber up to 100m at 850nm via duplex LC connector — the numeric part number equivalent to SFP-25G-SR-C, providing the same 25G MMF short-reach capability for Juniper QFX, MX, and PTX platforms through Juniper's numeric ordering system.

Key Features

• 25GBASE-SR SFP28 for 100m 25GbE over OM4 MMF — numeric alternative to SFP-25G-SR-C
• 850nm VCSEL for standard OM3/OM4 multi-mode fiber duplex LC infrastructure
• Juniper numeric part 740-068639 — functionally interchangeable with SFP-25G-SR-C
• DDM/DOM support for real-time optical monitoring via Junos OS
• Low-power SFP28 for high-density 25G MMF deployments in Juniper chassis

Product Specifications

• Part Number: 740-068639
• Manufacturer: Juniper Networks
• Form Factor: SFP28
• Speed: 25GbE (25GBASE-SR)
• Wavelength: 850nm (VCSEL)
• Connector: Duplex LC
• Fiber Type: Multi-Mode Fiber (MMF, OM3/OM4)

Transceiver & Interface Specifications

• Max Distance: 100m (OM4 MMF), 70m (OM3 MMF)
• TX Power: -8.5 to -1 dBm
• RX Sensitivity: -11.1 dBm (min)
• Power Consumption: Typically 1.0W
• DDM/DOM: Yes
• Operating Temperature: 0°C to 70°C (commercial)

Use Cases

• 25GbE server-to-switch MMF uplinks in Juniper QFX top-of-rack deployments
• Short-reach 25G inter-switch links in spine-leaf architectures using OM3/OM4 MMF
• Numeric part number procurement for 25GBASE-SR SFP28 capacity on Juniper platforms
• 4x25G breakout receiving end from 100G QSFP28 SR4 via MPO-to-LC fan-out cables

Compatibility

• Compatible with Juniper QFX, MX, and PTX platforms with SFP28 25G ports
• Requires OM3 or OM4 multi-mode fiber with duplex LC connectors
• Fully interchangeable with SFP-25G-SR-C on supported Juniper platforms
• IEEE 802.3by 25GBASE-SR compliant

Frequently Asked Questions

What is the difference between 740-068639 and SFP-25G-SR-C?

Both are Juniper-genuine 25GBASE-SR SFP28 transceivers with identical optical specifications. The 740-068639 uses Juniper's numeric part number format, while SFP-25G-SR-C uses the alphanumeric format. Both are fully interchangeable on supported Juniper platforms — choose based on your procurement system's preferred format.

What is the maximum distance on OM3 vs. OM4 fiber?

On OM3 fiber, 25GBASE-SR supports up to 70m. On OM4 fiber, reach extends to 100m. OM4 is recommended for cross-row and end-of-row switch distances, while OM3 is typically sufficient for in-rack and top-of-rack server uplink distances under 70m.

Does the 740-068639 support Digital Diagnostics Monitoring?

Yes — DDM/DOM is supported, enabling Junos OS to report TX/RX optical power, temperature, voltage, and laser bias current in real time for proactive transceiver health monitoring via CLI and SNMP.

The Juniper 740-068639 delivers 25GBASE-SR SFP28 performance in the numeric part number format — providing the same 100m OM4 MMF reach, DDM monitoring, and Juniper platform compatibility as the SFP-25G-SR-C alphanumeric variant for 25G short-reach MMF deployments on Juniper QFX, MX, and PTX platforms.