Introduction and general concepts; Channel multiplexing; Time division multiplexing (TDM); Polarization division multiplexing; Wavelength division multiplexing (WDM); Nonlinear impairments; Combined effects of dispersion and SPM; Interchannel impairments; Intrachannel impairments; Nonlinear phase noise; Electronic dispersion compensation; Advanced optical modulation formats; Frequency shift keying; Phase shift keying; Polarization shift keying; Principle of coherent detection; Practical constraints of coherent transmission; Demodulation scheme; Heterodyne detection; Homodyne detection; Intradyne detection; Polarization diversity reception; OFDM optical transmission systems; Basics of optical networks.