Hyun-Gyoo Yook

Scheduling GEN_BLOCK Array Redistribution

This article is devoted to the redistribution of arrays that are distributed in a GEN_BLOCK fashion over a processor grid. While GEN_BLOCK redistribution is essential for load balancing, prior research about redistribution has been focused on block-cyclic redistribution. The proposed scheduling algorithm exploits a spatial locality in message passing from a seemingly irregular array redistribution. The algorithm attempts to obtain near optimal scheduling by trying to minimize communication step size and the number of steps. According to experiments on CRAY T3E and IBM SP2, the algorithm shows good performance in typical distributed memory machines.

Guest access: change even your mother into an effective security technician

This paper presents an easy and secure mechanism that supports temporal network access for a guest device. A conventional wireless home network secured based on WPA has a critical security hole when a guest device revisits your home network. Once a pre-shared key (PSK) is exposed to the guest device, the device can connect your home network at any time without additional permission. In order to solve this problem, the proposed mechanism keeps the PSK on a smart card, which provides only temporal keys to the guest device. It also supports usability by minimizing user interaction steps and being based on an intuitive mental model.