With the remarkable advantages of thin-client computing (TCC) on security enhancement and cost reduction, the TCC architecture seemed appropriate for EPR utilization in cross-border e-health systems. The advantage in less consumed network bandwidth, however, still remains quantitatively unidentified at present. This study aimed to estimate the network traffic required in using EPR on WAN environments through the comparison of TCC and server-client (SC) models The results indicated that one of representative TCC applications required much less network bandwidth than the conventional SC model. Further studies will be focused on the verification of the adopted scenarios and a combination of applications that would affect the estimation of the network bandwidth.