Radio frequency over glass

In telecommunications, radio frequency over glass (RFoG) is a deep-fiber network design in which the coax portion of the hybrid fiber coax (HFC) network is replaced by a single-fiber passive optical network (PON). Downstream and return-path transmission use different wavelengths to share the same fiber (typically 1550 nm downstream, and 1310 nm or 1590/1610 nm upstream). The return-path wavelength standard is expected to be 1610 nm, but early deployments have used 1590 nm. Using 1590/1610 nm for the return path allows the fiber infrastructure to support both RFoG and a standards-based PON simultaneously, operating with 1490 nm downstream and 1310 nm return-path wavelengths. rdf:langString