Cisco Compatible GLC-BX-U-1490D-120 / GLC-BX-D-1550D-120 BiDi SFP Transceiver | 1GBASE-BX, 1490/1550nm, LC Simplex, SMF (120km)
Product Overview
The Cisco Compatible GLC-BX-U-1490D-120 and GLC-BX-D-1550D-120 BiDi SFP Transceivers are carrier-grade 1Gbps single-fiber optical modules engineered for ultra-long-distance transmission up to 120 kilometers over single-mode fiber (SMF). Using Wavelength Division Multiplexing (WDM) technology, they operate at 1490nm and 1550nm wavelengths, enabling full-duplex communication over a single fiber strand.
Designed for long-haul telecom, backbone infrastructure, and high-capacity metro networks, these modules provide exceptional optical budget, low attenuation, and high link stability, making them suitable for the most demanding long-distance deployments.
Fully compatible with Cisco platforms, they offer a reliable, scalable, and cost-efficient alternative to OEM optics.
Wavelength Configuration & Pairing
✔ Correct Pairing:
1490/1550 ↔ 1550/1490 → Full-duplex over single fiber
Key Features
- Supports 1Gbps data rate (1000BASE-BX)
- Single-fiber (BiDi) transmission via WDM technology
- TX/RX wavelengths: 1490nm / 1550nm
- Up to 120km transmission over SMF
- Hot-pluggable SFP form factor
- Fully compatible with Cisco SFP ports
- Reduces fiber usage by 50%
- Ultra-high optical budget for long-haul transmission
- Optimized for backbone and carrier networks
- MSA compliant and fully tested
Technical Specifications
General Parameters
- Transmission Distance: Up to 120km
- Fiber Type: Single-Mode Fiber (SMF)
Optical Characteristics
- Transmitter Type: DFB Laser (high output)
- Receiver Type: APD Photodiode
- RX Sensitivity: ≤ -30 dBm
Electrical & Environmental
- Power Consumption: ≤ 1.8W
- Operating Temperature: 0°C to 70°C (Industrial options available)
- Storage Temperature: -40°C to 85°C
Compliance
- IEEE 802.3ah (1000BASE-BX)
Why 1490/1550nm for 120km?
For ultra-long-distance transmission, this wavelength combination is essential:
- 1550nm wavelength → lowest fiber attenuation (~0.2 dB/km)
- Higher launch power → extended reach capability
- APD receiver → enhanced sensitivity for weak signals
These factors enable stable transmission over 100km+ distances where standard optics cannot operate.
Applications
- Long-haul telecom backbone networks
- Metro core and inter-city connectivity
- ISP carrier-grade infrastructure
- Large-scale enterprise WAN links
- Fiber-limited ultra-long-distance deployments
Important Deployment Notes
For 120km links, additional components may be required:
- Optical amplifiers (EDFA)
- Dispersion compensation modules (DCM)
- Optical attenuators (for short spans)
👉 Proper optical link budget calculation is strongly recommended before deployment.
Pairing Note (Critical)
BiDi modules must always be deployed in complementary pairs:
✔ 1490/1550 ↔ 1550/1490 → ✅ Works
❌ Same wavelength modules → ❌ No link
Why Choose This Product
The Cisco-compatible GLC-BX-U-1490D-120 / GLC-BX-D-1550D-120 modules are designed for extreme-distance networking scenarios. They offer:
- Ultra-long reach up to 120km
- High optical performance with minimal signal loss
- Reduced fiber infrastructure cost (single fiber)
- Carrier-grade reliability for mission-critical links
They are ideal for deployments where distance, performance, and network resilience are non-negotiable.
When to Choose This Module
Choose this 120km BiDi series if:
✔ Distance requirement exceeds 80km
✔ Deploying in backbone or inter-city networks
✔ Need maximum optical reach and stability
✔ Fiber resources are limited
Choose 80km modules if:
✔ Distance is shorter
✔ Lower cost and power consumption are preferred
Cisco compatible GLC-BX-U-1490D-120, GLC-BX-D-1550D-120, 1G BiDi SFP 120km, 1490/1550 SFP long distance, 1000BASE-BX ultra long reach, single fiber SFP Cisco
