1. The name of XGPON and XGSPON, and the each alphabet stands for,

First of all, we need to know the full name of them.

XGPON means 10 Gigabit Passive Optical Network, in which “X” is Latin letter stands for “10“, “G” is Gigabit, In data communications, a gigabit is one billion bits, or 1,000,000,000 (that is, 109) bits. It’s commonly used for measuring the amount of data that is transferred in a second between two telecommunication points. ”PON” means “Passive Optical Network“, A passive optical network means the signal running on fiber instead of copper cable, no need of the electrical power to maintain the signal from devices OLT to ONU.

XGSPON means 10 Gigabit Symmetrical Passive Optical Network, in which “X” is Latin letter stands for “10“. “G” is Gigabit, “S” stands for Symmetrical, which means the uplink and downlink speed is the same 10 Gigabit. “PON” means “Passive Optical Network”

2. The difference of the XGPON and XGSPON.

After we explain the name, you could find that the difference is only the “S” different, have it or not.

XGPON have an asymmetrical uplink and downlink speed. XGPON’s uplink speed 2.5G and downlink speed 10G.

XGPON have an asymmetrical uplink and downlink speed. XGSPON’s uplink speed 10G and downlink speed 10G, too.

Note: some XGSPON OLT support uplink and downlink speed in both way, because the network rate is generally designed to be backward compatible to maximize the range of equipment, for example, a port that supports 10G can also support 2.5G.