The change over from IPv4 to IPv6 entails a potential increase in the number of records that the Registry System must maintain. Currently, only a few Network Information Centers (NICs), controlled by Internet Assigned Number Authority (IANA), operate their Registry Systems. As they concentrates data into several Registry System, it is not scalable. This paper focuses on the scalability issue in a Registry System and Mie Advanced Registry System (MARS) is proposed. Through the collaboration of independent Registry Systems, MARS ensures data consistency as well as making it possible to access data managed by other Registry Systems. A prototype system of MARS is implemented, maintained and managed on the WIDE 6bone. Some lessen from the operation of MARS give also described.

IPv6 is realized as the next generation internet platform, succeeding the current IPv4 internet environment. Linux, one of the major operating systems, has supported IPv6 since 1996, however, the quality of the protocol stack has not been good enough for professional operation. In this paper, we show our IPv6 stack implementation design regarding the neighbor management in Neighbor Discovery Protocol (NDP), the routing table management and the packet processing using XFRM architecture. The implementation is designed based on the Serialized Data State Processing, which aims at simpler object management so as to achieve stable, flexible and extensible IPv6 stack. According to the TAHI IPv6 Protocol Conformance Test Suite, we can show our implementation achieves enough implementation quality.

Many services on the Internet are provided by multiple identical servers in order to improve performance and robustness. The number, the location and the distribution of servers affect the performance and reliability of a service. The server placement is, however, often determined based on the empirical knowledge of the administrators. This paper investigates issues of the server placement in terms of the service performance and the server load. We identify that a server selection mechanism plays an important role in server placement, and thus, evaluate different server selection algorithms. The result shows that it is essential to the robustness of a service to employ a mechanism which distributes service requests to the servers according to the measured response time of each server. As a case study, we evaluate the server selection mechanisms employed by different DNS (Domain Name System) implementations. Then, we show the effects of the different server selection algorithms using root-server measurements taken at different locations around the world.