摘要：The paper is focused on available server management in Internet connected netw.rk environments. The local backup servers are hooked up by LAN and replace broken main server immediately and several different types of backup servers are also considered. The remote backup servers are hooked up by VPN (Virtual Private Netw.rk) w.th high-speed optical netw.rk. A Virtual Private Netw.rk (VPN) is a w.y to use a public netw.rk infrastructure and hooks up long-distance servers w.thin a single netw.rk infrastructure. The remote backup servers also replace broken main severs immediately under the different conditions w.th local backups. w.en the system performs a mandatory routine maintenance of main and local backup servers, auxiliary servers from other location are being used for backups during idle periods. Analytically tractable results are obtained by using several mathematical techniques and the results are demonstrated in the framew.rk of optimized netw.rked server allocation problems. The operational w.rkflow.give the guidelines for the actual implementations.