Developing services and innovative access technologies on the user side higher bandwidths, the GPON technology cannot meet bandwidth requirements, these factors promoting the GPON technology evolution to 10G GPON, as shown in Figure 1. XG-PON and XGS-PON belong to the 10G GPON technology.
XG-PON: 10-Gigabit-capable passive optical network, provides asymmetric 10G transmission (Maximum downstream line rate: 9.953 Gbit/s, Maximum upstream line rate: 2.488 Gbit/s ).
XGS-PON: 10-Gigabit-capable symmetric passive optical network, provides symmetric 10G transmission (Maximum downstream line rate: 9.953 Gbit/s, Maximum upstream line rate: 9.953 Gbit/s ).
Figure 2 shows the smooth evolution from the GPON network to the 10G GPON network by adding the WDM1r wavelength division multiplexing (WDM) equipment.