• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.17 no.8
• /
• pp.823-836
• /
• 1992

Computer and communication network of the future will be the ISDN that enable various services. And now, it Is very Important to study the relevalent techniques to develop Interworking methods between existing computer network and ISDN The purpose of this paper Is to provide necessary basic He search results on the Interworkting method between local area network (LAN) and ISDN. For Interworking, we analyze the characteristic of existing LAN and ISDN and discuss considerations of Interworking and suggest the interworking method for CO and CL services. Also. we construct logical gateway for Interworking betwen LAN and ISDN and make formairnodeling of gateway using Petri net and verify the correctness of protocol with reachability tree. Research results should be helpful In designing and Implementing gateway between i()cal computer network and I SDN

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.7
• /
• pp.471-478
• /
• 2013

This paper proposes a black-box based test case generation method for Simulink/Stateflow model utilizing the RRT algorithm which is a method to efficiently solve the path planning for complicated systems. The proposed method in the paper tries to solve the reachability problem with the RRT algorithm, which has to be solved for black-box based test case generations. A major problem of the RRT based test case generation algorithms is that the cost such as running time and required memory size is too much for complicated Stateflow model. The typical RRT algorithm expands rapidly-exploring random tree (RRT) in a single state space. But the proposed method expands it in dynamic state space based on the state of Simulink model, consequently reducing the cost. In the paper, a new definition of RRT state space, a distance measure and a test case generation algorithm are proposed. The performance of proposed method is verified through the experiment against Stateflow model.

• The KIPS Transactions:PartC
• /
• v.9C no.1
• /
• pp.97-106
• /
• 2002

In 3GPP2 standard, MIP is used and a PDSN performs the function of FA to support macro mobility. When a MS is roaming from a PDSN area to another, the mobility supported is called macro mobility, while it is called micro mobility when a MS is roaming from a RN area to another in a PDSN area. Since a PDSN performs the function of FA in 3GPP2 standard, it is possible to support mobility but its mechanism is actually for supporting macro mobility, not for micro mobility, thus it is weak in processing fast and seamless handoff to support micro mobility. In this paper, we suggest the seamless handoff algorithm barred on multicast group mechanism to support micro mobility. Depending on the moving direction and velocity of a MS, the suggested algorithm constructs a multicast group of RNs on the forecasted MS's moving path, and maximally delays RNs'joining to a multicast group to increase the network efficiency. Moreover, to resolve the buffer overhead problem of the existent multicast scheme, the algorithm suggests that each RN buffers data only after the forecasted handoff time. To prove deadlock freeness and liveness of the algorithm. we use state transition diagrams, a Petri-net modeling and its reachability tree. Then, we evaluate the performance by simulation.