GBIC vs SFP: Differences and Choose Guide

Both GBIC modules and SFP modules are input/output (I/O) devices that plug into network switches or routers that have Gigabit Ethernet ports, supporting 1000BASE-X optical fiber links. This article provides a comprehensive introduction to the GBIC (Gigabit Interface Converter) module and SFP (Small Form-factor Pluggable) module. Do you know the difference between GBIC vs SFP? If not, don't worry, in this blog post, we will discuss the differences between GBIC and SFP. We will also help you decide which one is right for your business. So, let's get started!

What is GBIC?

GBIC is short for Gigabit Interface Converter. It is a hot-pluggable interface device that converts Gigabit electrical signals into optical signals. GBIC standard is first defined in 1995. Then GBIC modules are commonly used in Gigabit Ethernet and Fiber Channel by connecting to transmission media like fiber optic cables and copper cables. GBIC got popular in the 1990s. The GBIC connector is designed to support reliable operation at 1Gbit/s in the form of SC duplex connectors. 

The typical GBIC transceiver include 1000BASE-SX GBIC, 1000BASE-LX/LH GBIC, and 1000BASE-ZX GBIC. They cover short, long, and extended wavelengths. Their specifications are shown in the following table.

What is SFP?

SFP refers to Small Form-factor Pluggable. It is similar to the GBIC in function, a hot-pluggable interface module used for electrical signal and optical signal converting, so SFP is also called GBIC SFP. However, the size of SFP is much smaller than the GBIC, so SFP is also known as Mini-GBIC. SFP transceivers support Gigabit Ethernet, Fibre Channel, SONET, PON, and other communications standards. Same as GBIC, the typical speed of SFP is also 1 Gbit/s, but its connector form is LC connector instead of SC.

Similar to GBIC, the common SFP types include 1000BASE-SX SFP, 1000BASE-LX/LH SFP and 1000BASE-ZX SFP. The corresponding Cisco product models are GLC-SX-MM, GLC-LH-SM, and GLC-ZX-SM. Their specifications are shown in the following table.

SFP Module Options

GBIC vs SFP, What are the differences?

GBIC vs SFP connector. All GBIC modules use SC connectors, and SFP modules use LC connectors. So when installing a GBIC module, you need a duplex SC fiber, while LC fiber is used for installing an SFP module.

GBIC vs SFP size. SFP is an upgraded version of GBIC. The most significant enhancement of SFP is the size. This SFP is smaller than half the size of GBIC, as shown in the following figure. A smaller size means higher density SFP ports are available on the same switch panel. It is the main reason why GBIC was replaced by SFP.

GBIC vs SFP compatibility. GBIC module has no variants, but SFP has variants such as SFP+ and SFP28, bringing speeds up to 10 Gbit/s and 25 Gbit/s. They have the same size as SFP, so SFP+ and SFP28 modules are backward compatible with SFP when the SFP module is plugged into SFP+ and SFP28 ports.

SFP or GBIC, How to choose

Firstly, if your switch or router is ready, how to choose between SFP and GBIC depends on your switch or router slots. SFP is not compatible with GBIC. Switches with only GBIC slots allow GBIC modules only, and so do SFP switches.

If you don’t have an existing switch or router, it is recommended to choose SFP equipment because SFP has many advantages over GBIC, such as higher density, better interoperability and compatibility. Most importantly, the fact is that GBIC has been replaced by SFP in practical applications. GBIC has become thoroughly outmoded, SFP is your right choice now.

Conclusion

GBIC and SFP are functionally similar, but SFP is more future-proof than GBIC in many ways, including smaller size, better compatibility and interoperability. It is consistent with the optical communication developing tendency of higher density, higher speed, and lower power consumption.

QSFPTEK offers a wide range of SFP transceivers for your Gigabit Ethernet and Fibre Channel applications. These small, modular optical interface transceivers offer a convenient and cost-effective solution for data center, campus, metropolitan area access, and storage area networks. If you have further questions on GBIC vs SFP or need any help with the SFP products, welcome to consult via sales@qsfptek.com.