On Demand Multicast Routing in Wireless Sensor Networks

On Demand Multicast Routing in Wireless Sensor Networks

which can be very beneficial for a number of test-related problems. On Demand Multicast Routing in Wireless Sensor Networks Fault Ordering Effect on Relaxation The algorithm is fault-based which implies that the obtained results depend on the order in which the various faults are examined. The decision on which tests must explicitly detect each fault is taken based on the gain function which is computed using the contribution, in specified bits, of each fault in each test This contribution changes during the relaxation process, On Demand Multicast Routing in Wireless Sensor Networks since every fault detection that is removed from each test’s fault list for test changes the relations between the bits in the considered test for the faults considered. consider a test that detects three faults The contributions and specified bits, respectively.

Assume that, when removing the first two bits become don’t care whereas when removing bit of the test becomes a don’t care. Removing results in unspecifying the last two bits of the test bits and Also, assume that bits and become don’t cares if both faults and are removed from and bit becomes a don’t care if both faults and are removed from . On Demand Multicast Routing in Wireless Sensor Networks Let us concentrate on the contribution of fault and assume that this fault is examined second. If the algorithm examines first and the decision is to remove from , then the contribution of If the algorithm examines fault first and removesit form , then the contribution of the fault becomes When the decision on fault is to be made, the outcome may change depending on which of and has been examined first. summarizes the changes in the faults contribution for different orderings. For real circuits, the faults contribution change range can become very large, especially with -detect test sets where the average number of detections is larger and, thus, each test’s list of detected faults is larger.

On Demand Multicast Routing in Wireless Sensor Network

On Demand Multicast Routing in Wireless Sensor Networks The latter implies that the ordering of the examination of the considered faults has impact on the final ratio of specified bits in the test set. Next, we give experimental results for the proposed test relaxation method under a number of different fault orderings. Specifically, our experimentation investigates the following five different fault orderings topological order of faults examine faults closer to the primary inputs first decreasing on the number of tests detecting each fault increasing on the number of tests detecting each fault; decreasing on the number of tests detecting each fault, in the initial test set; increasing on the number of tests detecting each fault, in the initial test set. Orderings actually sort faults based on the number of tests that detect them on the initial test set. On Demand Multicast Routing in Wireless Sensor Networks This information can be easily obtained by the fault simulation procedure preceding the main algorithm application.

examines faults based on the order the corresponding circuit lines are visited during a topological traversal of the circuit’s graph. A topological order can be obtained in linear, to the size of the circuit’s graph, time. Orderings are different from and since they consider all tests that detect the corresponding fault obtained by a test generation process. Since, in our experimentation the test generation carried out by a BDD-based framework, we are able to obtain accurate information on the total number of tests that exist for each fault efficiently. The latter can be done by counting the number of minterms in the test function corresponding to each fault, which is a linear operation on the BDD size.