GLC-GE-100FX-BCC | Cisco Compatible 100MB Multi-Mode for 1GB Ports - 2km (100BASE-FX)

Q: Will this work in place of the Cisco GLC-GE-100FX?
A: Yes. The GLC-GE-100FX-BCC provides drop-in compatibility with the Cisco GLC-GE-100FX. It conforms to the same 100BASE-FX standard, matches the SFP form factor, operates at 1310nm over multi-mode fibre to 2km, and supports DOM. It is plug-and-play compatible in Gigabit Ethernet SFP ports on Cisco switches and routers that accept the original Cisco module.

Q: Which Cisco platforms support this module?
A: This module operates in Gigabit Ethernet SFP ports on Cisco switches and routers. It has been confirmed compatible with Catalyst 2960, 2970, 3560, 3650, 3750, and Industrial Ethernet platforms. The host port must support SGMII protocol to enable 100 Mbps operation in a Gigabit slot.

Q: What is the difference between this 100BASE-FX module and a standard Gigabit SFP?
A: This module operates at 100 Mbps using the IEEE 802.3u 100BASE-FX standard, while standard Gigabit SFPs run at 1000 Mbps. It enables Fast Ethernet connectivity in Gigabit SFP slots via SGMII encoding, where the MAC transmits at 1.25 Gbps with 10x byte repetition and the module PHY converts it to 100BASE-FX signaling. This allows legacy 100 Mbps equipment or fibre links to connect to modern Gigabit switches without dedicated Fast Ethernet ports.

Q: Can this module achieve 2km reach on both 50 and 62.5 micron multi-mode fibre?
A: Yes. The 1310nm wavelength minimizes modal dispersion on multi-mode fibre, enabling 2km reach on both 50/125 and 62.5/125 micron MMF per the 100BASE-FX specification. The transmitter provides -20 to -14 dBm output power, and the receiver sensitivity extends to -31 dBm, yielding sufficient link budget for 2km spans assuming clean connectors and typical fibre loss (3.5 dB/km at 1310nm for MMF).

Q: Does this module support auto-negotiation or require manual port configuration?
A: This module does not support auto-negotiation. The host Gigabit Ethernet port must be manually configured for 100 Mbps full-duplex operation. The SGMII PHY within the module handles speed conversion between the 1.25 Gbps host interface and 100 Mbps 100BASE-FX line rate, but the port speed setting must be explicitly set to 100 Mbps on the switch or router.