  This letter characterizes the optimal policies for bandwidth use and storage
for the problem of distributed storage in Internet of Things (IoT) scenarios,
where lost nodes cannot be replaced by new nodes as is typically assumed in
Data Center and Cloud scenarios. We develop an information flow model that
captures the overall process of data transmission between IoT devices, from the
initial preparation stage (generating redundancy from the original data) to the
different repair stages with fewer and fewer devices. Our numerical results
show that in a system with 10 nodes, the proposed optimal scheme can save as
much as 10.3% of bandwidth use, and as much as 44% storage use with respect to
the closest suboptimal approach.
