GLC-FE-100LX-BCC | Cisco Compatible 100MB Single-Mode - 10km (100BASE-LX)

Q: Will this work in place of the Cisco GLC-FE-100LX?
A: Yes. The GLC-FE-100LX-BCC is a drop-in replacement for the Cisco GLC-FE-100LX. It matches the SFP form factor, 100Mbps data rate, 1310nm wavelength, and 10km reach over single-mode fibre. Plug-and-play compatibility is provided through IEEE 100BASE-LX10 compliance, and it operates in Fast Ethernet or dual-rate Fast/Gigabit Ethernet SFP ports.

Q: Which Cisco platforms support this transceiver?
A: This SFP operates in any Cisco device with a Fast Ethernet SFP port or a dual-rate Fast/Gigabit Ethernet SFP port that supports 100BASE operation. Common applications include switches with Fast Ethernet uplinks, routers with integrated services slots accepting SFPs, and Gigabit Ethernet ports configured to negotiate 100Mbps. Compatibility is determined by the port type and speed negotiation capability, not specific platform models.

Q: What fibre type and quality is required to achieve 10km reach?
A: This transceiver requires single-mode fibre compliant with ITU-T G.652 (standard SMF). The 10km reach specification assumes a maximum link loss budget based on typical fibre attenuation at 1310nm. Actual distance depends on cumulative insertion loss from patch panels, connectors, splices, and fibre attenuation. Clean LC connectors and low-loss terminations are essential to maintain the optical budget over the full 10km span.

Q: Can I access DOM data, and what parameters are available?
A: Yes, this SFP supports Digital Optical Monitoring (DOM) per SFF-8472. You can read real-time diagnostics including transmit optical power, receive optical power, transceiver temperature, supply voltage, and laser bias current via the I2C interface. These parameters are exposed through CLI commands (such as 'show interfaces transceiver' on Cisco IOS) or SNMP for remote monitoring and threshold alarming.

Q: What happens if I install this SFP in a Gigabit Ethernet port?
A: In a dual-rate Fast/Gigabit Ethernet port, the transceiver will negotiate 100BASE-LX operation. Gigabit-only ports typically do not support 100BASE-LX SFPs. Before deployment, confirm that the target port supports dual-rate or Fast Ethernet speed negotiation. The SFP will not damage a Gigabit-only port but may not initialise or link if the port lacks 100Mbps capability.