  We investigate the fundamental information theoretic limits of cache-aided
wireless networks, in which edge nodes (or transmitters) are endowed with
caches that can store popular content, such as multimedia files. This
architecture aims to localize popular multimedia content by proactively pushing
it closer to the edge of the wireless network, thereby alleviating backhaul
load. An information theoretic model of such networks is presented, that
includes the introduction of a new metric, namely normalized delivery time
(NDT), which captures the worst case time to deliver any requested content to
the users. We present new results on the trade-off between latency, measured
via the NDT, and the cache storage capacity of the edge nodes. In particular, a
novel information theoretic lower bound on NDT is presented for cache aided
networks. The optimality of this bound is shown for several system parameters.
