SFPs 101: Six Fundamentals of SFP Transceivers

SFPs. Trying to understand the power and capabilities of these small networking devices can be confusing. Determining which transceiver and specs are best for your network is an even tougher obstacle. To eliminate some confusion, created a quick list of answers to fundamental questions about SFPs to help you get your network up and running. Let’s begin SFPs 101.ethernet optical transceiver module

1. What is an SFP transceiver?

Let’s start with the basics. SFP stands for “small form-factor pluggable.” SFP transceivers are compact and hot-pluggable devices that act as an interface between networking equipment (switch, router, network card) and interconnecting cabling (copper or fiber).

SFP transceivers are available with varying specifications allowing users to customize their networking equipment to meet their specific needs. Since SFPs are hot-pluggable they also make it easy for users to modify or upgrade network infrastructure. Available in single mode and multi mode, SFP transceivers, depending on the type (SFP, SFP+, QSFP, QSFP+), can transmit data anywhere from as little as 500m to as far as 80km and provide transfer rates from 10 Mbps all the way to 40 Gbps.

2. What makes various SFPs different?

There are countless numbers of SFP transceivers and SFP cables on the market, so what makes them different and how do you know which is best for you?

Distance
The first differentiation users need to consider is distance. Do you need a Short Reach (SR) SFP or Long Reach (LR) SFP?

Single mode SFP transceivers can transmit anywhere from 2km all the way to 80km in distance. Standard Single mode SFPs can transmit up to 10km, while Extended Single mode SFPs, up to 80km.

For shorter distances, and a cheaper option, multi mode SFPs are a great solution. A Standard multi mode SFP can transmit up to 500m, while an Extended multi mode SFP, up to 2km.