A first network device comprising: a first receiver; and a first transmitter, wherein the first receiver and the first transmitter communicate with a second network device connected by a transformer and first and second power lines to the first network device and operate in a frequency band from 1 kHz to 600 kHz, wherein the first transmitter includes: an encoding module including an interleaver adapted to operate in a plurality of modes including a first mode and a second mode, the interleaver adapted to perform repetitive encoding on incoming data when placed in the second mode; and a modulation module in communication with the encoding module, the modulation module to compensate for attenuation that is to be realized during propagation of a signal transmitted over the power line (220, 230, 280), characterized in that the interleaver is adapted to generate an interleaved bit position (I,J) from an original bit position (i,j), where I = (a *i +b *j) %m and J= (c *j +d *1) %n, and where i, j, m, n, a, b, c, and d are all integers; where m denotes number of subcarriers in each OFDM symbol; n denotes number of OFDM symbols in each interleaving block; and a, b, c, and d denote amount of circular shifts; and the modulation module further including an adaptive tone mapping module to modulate an output of the encoding module to selected orthogonal tones located in the frequency band based on a tone map, wherein the tone map is selectively adjusted by the second network device. a first receiver; and a first transmitter, wherein the first receiver and the first transmitter communicate with a second network device connected by a transformer and first and second power lines to the first network device and operate in a frequency band from 1 kHz to 600 kHz, wherein the first transmitter includes: an encoding module including an interleaver adapted to operate in a plurality of modes including a first mode and a second mode, the interleaver adapted to perform repetitive encoding on incoming data when placed in the second mode; and a modulation module in communication with the encoding module, the modulation module to compensate for attenuation that is to be realized during propagation of a signal transmitted over the power line (220, 230, 280), an encoding module including an interleaver adapted to operate in a plurality of modes including a first mode and a second mode, the interleaver adapted to perform repetitive encoding on incoming data when placed in the second mode; and a modulation module in communication with the encoding module, the modulation module to compensate for attenuation that is to be realized during propagation of a signal transmitted over the power line (220, 230, 280), characterized in that the interleaver is adapted to generate an interleaved bit position (I,J) from an original bit position (i,j), where I = (a *i +b *j) %m and J= (c *j +d *1) %n, and where i, j, m, n, a, b, c, and d are all integers; where m denotes number of subcarriers in each OFDM symbol; n denotes number of OFDM symbols in each interleaving block; and a, b, c, and d denote amount of circular shifts; and the modulation module further including an adaptive tone mapping module to modulate an output of the encoding module to selected orthogonal tones located in the frequency band based on a tone map, wherein the tone map is selectively adjusted by the second network device. the interleaver is adapted to generate an interleaved bit position (I,J) from an original bit position (i,j), where I = (a *i +b *j) %m and J= (c *j +d *1) %n, and where i, j, m, n, a, b, c, and d are all integers; where m denotes number of subcarriers in each OFDM symbol; n denotes number of OFDM symbols in each interleaving block; and a, b, c, and d denote amount of circular shifts; and the modulation module further including an adaptive tone mapping module to modulate an output of the encoding module to selected orthogonal tones located in the frequency band based on a tone map, wherein the tone map is selectively adjusted by the second network device.