e-VLBI was invented to enhance the efficiency of VLBI (Very-Long-Baseline Interferometry) system by transmitting the data via high speed network. Korean VLBI Network (KVN) has a plan to construct e-VLBI system named e-KVN. High speed backbone network and efficient network model are essential to implement successful e-VLBI system. This paper introduces a network model based on PC cluster technology. The present status of high speed backbone network in Korea is overviewed. We suggest that the network link via Korea Advanced Research Network (KOREN) is one of feasible way for e-KVN. We also describe the principles of e-VLBI and protocol for network transmission such as VSI-E (VLBI Standard Interface - Electronic), RTP (Real-Time Transport Protocol) and RTCP (Real-Time Transport Control protocol).