The Paging Algorithm
Consider a paging event at time t = τ, for a user u with roaming interval equal to τ, whose last known location, at time t = 0, is X0.
The distance between two cells, say x and y, denoted by d(x, y), is defined as the length of the shortest path between x and y, measured of cells.
The goal is to minimize the number of locations at which the user is paged.