Information Freshness in Cache Updating Systems

We consider a cache updating system with source, and user. There are $n$ files. The source keeps the freshest version of files which updated known rates $\lambda _{i}$ . downloads from $c_{i}$ user gets updates $u_{i}$ When an update, it either fresh update or file at becomes outdated by in case update. find analytical expression for average freshness Next, we generalize our setting to where there multiple caches between user, provide alternating maximization based method cache(s), , maximize observe that given set (resp. cache), optimal rate allocation policy user) is threshold rapidly changing may be equal zero. Finally, users connected single total over all users.