In this paper, there is presented a review of our today's understanding of the ultimately broadband photonic Internet. A
simple calculation is presented showing the estimate of the throughput of the core photonic network branches.
Optoelectronic components, circuits, systems and signals, together with analogous electronic entities and common
software layers, are building blocks of the contemporary Internet. Participation of photonics in development of the
physical layer in the future Internet will probably increase. The photonics leads now to a better usage of the available
bandwidth (increase of the spectral efficiency measured in Bit/s/Hz), increase in the transmission rate (from Gbps, via
Tbps up to probably Pbps), increase in the transmission distance without signal regeneration (in distortion compensated
active optical cables), increase in energy/power efficiency measured in W/Gbps, etc. Photonics may lead, in the future,
to fully transparent optical networks and, thus, to essential increase in bandwidth and network reliability. It is expected
that photonics (with biochemistry, electronics and mechatronics) may build psychological and physiological interface
for humans to the future global network. The following optical signal multiplexing methods were considered, which are
possible without O/E/O conversion: TDM-OTDM, FDM-CO-OFDM, OCDM-OCDMA, WDM-DWDM.