  The ever-continuing explosive growth of on-demand content requests has
imposed great pressure on mobile/wireless network infrastructures. To ease
congestion in the network and increase perceived user experience, caching
popular content closer to the end-users can play a significant role and as such
this issue received significant attention over the last few years.
Additionally, energy efficiency is treated as a fundamental requirement in the
design of next-generation mobile networks. However, there has been little
attention to the overlapping area between energy efficiency and network caching
especially when considering multipath routing. To this end, this paper proposes
an energy-efficient caching with multipath routing support. The proposed scheme
provides a joint anchoring of popular content into a set of potential caching
nodes with optimized multi-path support whilst ensuring a balance between
transmission and caching energy cost. The proposed model also considers
different content delivery modes, such as multicast and unicast. Two separated
Integer-Linear Programming (ILP) models are formulated for each delivery mode.
To tackle the curse of dimensionality we then provide a greedy simulated
annealing algorithm, which not only reduces the time complexity but also
provides a competitive performance as ILP models. A wide set of numerical
investigations has shown that the proposed scheme is more energy-efficient
compared with other widely used approaches in caching under the premise of
network resource limitation.
