In this paper, we present a Mobile Agents based Framework for Routing and Congestion control in Mobile Ad Hoc Networks (MAFRC). The framework uses a cross-layer design approach where multiple intelligent agents present across the network protocol stack cooperate with each other and aid in finding efficient routes between source and destination pairs and also in controlling congestion in the network. The mobile agents at the network layer moving across the network collect the network connectivity information based on the congestion state provided by the static agent at the link layer. The congestion information brought by these mobile agents is further used in controlling congestion at the transport layer. This multi-agent cross-layer framework has been implemented and a preliminary performance evaluation has been carried out for the congestion aware routing and the cross-layer congestion control scheme in a simulation environment using NS-2 simulator. The results show better performance with respect to the performance parameters such as network throughput, end-to-end delay and routing overhead when compared to the network architecture which uses Ad Hoc On-demand Distance Vector (AODV) as a standard routing protocol and Tahoe TCP.

The problem of determining a minimal number of control inputs for converting a programmable logic array (PLA) with undetectable faults to crosspoint-irredundant PLA for testing has been formulated as a nonstandard set covering problem. By representing subsets of sets as cubes, this problem has been reformulated as familiar problems. It is noted that this result has significance because a crosspoint-irredundant PLA can be converted to a completely testable PLA in a straightforward fashion, thus achieving very good fault coverage and easy testability.>

An on-line algorithm is developed for the location of single cross point faults in a PLA (FPLA). The main feature of the algorithm is the determination of a fault set corresponding to the response obtained for a failed test. For the apparently small number of faults in this set, all other tests are generated and a fault table is formed. Subsequently, an adaptive procedure is used to diagnose the fault. Functional equivalence test is carried out to determine the actual fault class if the adaptive testing results in a set of faults with identical tests. The large amount of computation time and storage required in the determination, a priori, of all the fault equivalence classes or in the construction of a fault dictionary are not needed here. A brief study of functional equivalence among the cross point faults is also made.

In this paper, the validity of single fault assumption in deriving diagnostic test sets is examined with respect to crosspoint faults in programmable logic arrays (PLA's). The control input procedure developed here can be used to convert PLA's having undetectable crosspoint faults to crosspoint-irredundant PLA's for testing purposes. All crosspoints will be testable in crosspoint-irredundant PLA's. The control inputs are used as extra variables during testing. They are maintained at logic 1 during normal operation. A useful heuristic for obtaining a near-minimal number of control inputs is suggested. Expressions for calculating bounds on the number of control inputs have also been obtained.