Tokyo Tyrant is a package of network interface to the DBM called Tokyo Cabinet. Though the DBM has high performance, you might bother in case that multiple processes share the same database, or remote processes access the database. Thus, Tokyo Tyrant is provided for concurrent and remote connections to Tokyo Cabinet. It is composed of the server process managing a database and its access library for client applications. The server features high concurrency due to thread-pool modeled implementation and the epoll/kqueue mechanism of the modern Linux/*BSD kernel. The server and its clients communicate with each other by simple binary protocol on TCP/IP. Protocols compatible with memcached and HTTP/1.1 are also supported so that almost all principal platforms and programming languages can use Tokyo Tyrant. High availability and high integrity are also featured due to hot such mechanisms as hot backup, update logging, and replication.