Three main types of EPON are differentiating in speed and distance. 1000 BASE-PX10 is providing maximum distance of 10 km, while 1000 BASE-PX20 and 10G EPON maximum distance is 20 km.

 

Table 1. Features of 1000 BASE-PX10 and 1000 BASE-PX20.

 

Description	1000 BASE-PX10 Upstream	1000 BASE-PX10 Downstream	1000 BASE-PX20 Upstream	1000 BASE-PX20 Downstream
Data rate (Gbps)	1	1	1	1
Wavelength (nm)	1310	1490	1310	1490
Available power budget (dB)	23	21	26	26
Channel insertion loss (min/max, dB)	5/20	5/19.5	10/24	10/23.5
Allocation for penalties (dB)	3	1.5	2	2.5
Return loss (dB)	20	20	20	20
Max split ratio	1:16 (1:32 with FEC)	1:16 (1:32 with FEC)	1:16 (1:32 with FEC)	1:16 (1:32 with FEC)
Physical distance (km)	10	10	20	20

 

As shown in Table 1, first two types share the same symmetrical data rate of 1 Gbps upstream and downstream, as well as wavelengths of 1310 nm upstream and 1490 nm downstream. Split ratio is also the same for both types – 1:16 without FEC and 1:32 with FEC.
 

10G EPON supports both asymmetric and symmetric data rates. It can be either 10 Gbps downstream and 1 Gbps upstream or 10 Gbps both ways.