With the development of computer and network technologies and emerging of diverse types of terminal, the ability of network computing to tailor applications to the capabilities of heterogeneous client devices will realize its full potential at last. Most of the existing terminals first start OS locally and then load network-computing software. However, this booting way can’t satisfy the diversity of terminals and the increasing of complexity of network-computing software. A reliable, secure, effective and customizable remote boot protocol named as NCBP (network-based client boot protocol) is presented in this paper, which is hoped to increase the flexibility of existing network computing terminals’ booting process and thus increase the flexibility and availability of network computing. NCBP uses extended DHCP (dynamic host configuration protocol) to acquire local identifier, then loads a batch script language environment of MBatch (MenuBatch) by using secure APTP (active program transfer protocol). When executing the loaded MBatch script, NCBP allows users to select which OS to be loaded and then load the corresponding OS image in a customizable way. NCBP can be used for remote boot of network computers, PCs, and digital appliances.