Wavelength protection within coexistence of current and next-generation PON networks

Future development of broad-band access technologies expects increasing bandwidth demands under dynamic growth of FTTH across the world. Coexistence of current and next-generation PONs applying colorless ONUs sharing the same ODN infrastructure has been one of the most discussed issues nowadays especially for technical and commercial implications. This paper deals with some protective measures that can be easily deployed to avoid interferences between signals allocated to specific wavelength bands of current and next-generation PONs. There are several possibilities discussed how to separate and filter optical signals using wavelength blocking filters for GPON, XG-PON and other PON technologies to coexist.