(X1, Y1), Pactual (X2, Y2)) > ∆Tolerance, where ∆Tolerance is the tolerance distance), the point will send an update message (OID, Xold, Yold, Xnew, Ynew), which represents the movement of the point from location (Xold, Yold) to location (Xnew, Ynew), to the central ...