  Different polar coding schemes are proposed for the memoryless degraded
broadcast channel under different reliability and secrecy requirements: layered
decoding and/or layered secrecy. In this setting, the transmitter wishes to
send multiple messages to a set of legitimate receivers keeping them masked
from a set of eavesdroppers. The layered decoding structure requires receivers
with better channel quality to reliably decode more messages, while the layered
secrecy structure requires eavesdroppers with worse channel quality to be kept
ignorant of more messages. The implementation of the proposed polar coding
schemes is discussed and their performance is evaluated by simulations for the
symmetric degraded broadcast channel.
