  Nested codes have been employed in a large number of communication
applications as a specific case of superposition codes, for example to
implement binning schemes in the presence of noise, in joint network-channel
coding, or in physical-layer secrecy. Whereas nested lattice codes have been
proposed recently for continuous-input channels, in this paper we focus on the
construction of nested linear codes for joint channel-network coding problems
based on algebraic protograph LDPC codes. In particular, over the past few
years several constructions of codes have been proposed that are based on
random lifts of suitably chosen base graphs. More recently, an algebraic analog
of this approach was introduced using the theory of voltage graphs. In this
paper we illustrate how these methods can be used in the construction of nested
codes from algebraic lifts of graphs.
