“…We now discuss the content placement (CoP) problem, which entails deciding p c,v , the indicator function that network cache c stores video version v, for all c and v. As discussed in Section II, a major challenge to our optimization problem (1a)-(1f) is that the vector p needs to be updated much less frequently than the vector z. To address this challenge, we introduce pseudo-variables z := [z s,c,v ] and p := [p s,c,v ], which can be updated much more frequently than p, to replace z and p. 4 We only update p, the real content placement, after p converges. Also, we relax (1f) by allowing p c,v and z s,c,v to be any real number between 0 and 1.…”