GPON is inheriting lots of specifications from BPON. Signal is broadcasted downstream in the same manner. Upstream signal is relying on TDMA, the same way as it was in BPON. Most of other inherited specifications were enhanced – GPON is supporting higher rates, better security, increased bandwidth and etc.
 

Table 1. GPON and XG-PON1 Transmission Rates

 

Downstream (Gbps)	Upstream
1.24416	155.52, 622.08, 1244.16 Mbps
2.48832	155.52, 622.08, 1244.16, 248, 832 Mbps
9.95328	2.48832 Gbps

 

GPON and XG-PON1 transmission rates are shown in Table 1. IT is achieved by using large, variable length packets.

 

GPON encapsulation method (GEM) helps to improve QoS for video and voice traffic by reducing latency. It happens due GEM’s user traffic aggregation and frame segmentation.

Figure1. An example of GPON

 

Example of GPON upstream and downstream data transmission is shown in Figure 1.