Using Software Defined Network for the service upgrade of national R&E network requires replacing lots of legacy IP routers with SDN switches. Therefore, SDN migration should be carried out incrementally in order to reduce the instability of network service. A large ISP like Google prefers one by one migration of regional data centers that are scattered globally. Regional migration is appropriate only when the service architecture is very simple. For example, production of Google service is charged by Google data centers and consumption of them is the portion of remote users. But, in the case of national R&E network, service architecture is very complex because R&E network user, R&D experts, can be a service user and a service producer simultaneously when they do a collaborative research. Therefore, R&E network has to consider more factors in addition to region for incremental migration to SDN. In this paper, we suggest the detail framework and the practical methods of sustainable SDN migration that we had recently experienced during the softwarization of KREONET, Korea R&E network, and that were originally created as the solution of well-known problem of the legacy network, such as a last mile problem, inter-domain QoS exchange problem and so on. We call it Problem Solving Approach based SDN migration.
['Hyoung Woo Park', 'Il Sun Hwang', 'Jongsuk Ruth Lee']
Study on the Sustainable Migration to Software Defined Network for Nation-Wide R&E Network