| Differentiated Services (DiffServ) has been proposed for the next generation network. DiffServ allows the users to pay for and receive differentiated services. We realize that it is impractical to implement DiffServ in all nodes at the same time. Thus, it is reasonable to assume that the network will consist of both DiffServ capable nodes and DiffServ incapable nodes for quite some time. For DiffServ routing, DiffServ capable links are preferred. But a path consisting of only DiffServ capable nodes may not exist in the network. Even if such a path exists, it may not be the "optimal" path.; In this thesis, we give routing algorithms for a DiffServ capable user to establish a route in such a network. One of the routing metrics we consider is DiffServ capability. The other metric is cost. Three routing algorithms are given. In the first algorithm, cost is given higher precedence over DiffServ capability. In the second algorithm, DiffServ capability is given higher precedence over cost. The first two algorithms consider the metrics as independent metrics. In the third algorithm, we assign a DiffServ route selection order number to each link in the network topology. The algorithm computes the optimal path using the assigned DiffServ route selection order numbers.; Simulations in ns show that the third algorithm is more powerful than the first two algorithms. Through simulations, we have proved that the algorithm calculates the correct routing paths in all network topologies. |
