Mike's PBX Cookbook

Identifying SFPs
(Small Form-factor Pluggable)

SFP Media Types:

SFP Distance:

SFPTYPEMEDIAWAVELENGTHMAX DISTANCE
TBASE-TCopper (RJ45)N/A100m
SXShort ReachMMF OM1/OM2/
OM3/OM4/OM5
850nm1Gbps: 550m
155Mbps: 2km
LXExtended ReachSMF OS1/OS21310nm10km or 20km
EXExtended ReachSMF OS1/OS21310nm or 1550nm40km
ZXExtended ReachSMF OS1/OS21550nm70km or 80km
EZXExtended Long-ReachSMF OS1/OS21550nm160km
BXBi-directional (BiDi)SMF OS1/OS2, or MMF1310/1490nm, 1310/1550nm, 1490/1550nm80km

SFP Connector Type:

SFP single or multimode?

SFP and SFP+, although physically identical, are generally not compatible. SFP+ is "enhanced", and supports higher speeds (8G/10G/16G). Make sure that SFP's at both ends of a link match, with the same color coding! sfp_clasp.png

Wavelength Division Multiplexing (WDM):

Wavelength Division Multiplexing (WDM) is a way to increase the overall bandwidth by combining different light channels (wavelengths, or colors) on a single fiber. This technique enables bidirectional communications over a single strand. Passive CWDM uses a prism and bandpass filter to split the wavelengths without power, and is often used with fiber to the home (FTTH).

CWDM wavelength spacing is too wide for amplification, so its range is limited compared to DWDM:

CWDM Channels, wavelengths, and Clasp Colors: