The generalized postal model-broadcasting in a system with non-homogeneous delays

In many communication systems we may assume that every node is directly connected to every other node. It does not matter whether the system is a massively parallel computer where each processor is a node and the connectivity is achieved using a software communication library or if the system is the Internet where each node is a computer and the connectivity is achieved using IP. The postal model started with this assumption and in addition assumed that the process of delivering a message between two nodes takes a constant amount of time called the communication delay (greater than one unit of time), and that when a node sends a message or receives a message it wastes a single time unit. In this paper, we enhanced the postal model by removing the assumption that the communication delay is constant. Without this constraint. The broadcasting problem is NP-complete and therefore we study two directions. (i) We present heuristic algorithms and analyze them. (ii) We evaluate simple topologies of networks (by assuming large delays when there is not a direct connection). We have also tested the heuristic algorithms with simulations and compared them to the optimal solutions.