Of particular interest is the next-generation standard "NG-PON2" for PON (Passive Optical Network), which is widely used in home broadband services (FTTH).It is a new standard that increases the maximum transmission capacity per fiber from the current mainstream 1 Gbps to 40 Gbps at once (expandable to 80 Gbps as an option).The PON standards include ITU-T (International Telecommunication Union Telecommunication Standardization Division) "GPON" and IEEE (Institute of Electrical and Electronics Engineers) "EPON", and the communication methods and frequencies used are different. ..The maximum capacity is an asymmetric type with GPON up 1.25 Gbps / down 2.5 Gbps, and EPON up and down 1 Gbps.In Japan, the latter is predominant, and NTT's FLET'S Hikari and KDDI's au Hikari have adopted EPON (called "GE-PON" as a method unique to Japan).However, there are also examples of GPON adoption, such as some CATV companies and So-net, which provides NURO Hikari.GPON / EPON is still active, but it was standardized in the early 2000s.Around 2010, "10GE-PON" (IEEE) and "XG-PON1" (ITU-T) with a maximum transmission capacity of 10 Gbps were standardized, but they have not yet become widespread.So-net and others are only providing 10 giga services using XG-PON1, and major companies have not yet commercialized it.However, with the rise in traffic demand, the limits of GPON / EPON are becoming apparent.For example, if EPON is used in 32 branches, the bandwidth per subscriber when 32 subscribers access at the same time is about 30 Mbps.Looking ahead to the 4K / 8K era, there is an urgent need to upgrade.