The refined algorithm is put forward mainly based on the Wget. Combining the advantages of HTTrackand Wget, the download algorithm is rewritten on the following aspects: the download process is changed fromdepth-first retrieval to width-first retrieval; from single-socket to multi-socket; and from recursive retrieval to loopretrieval. The original process,which includes the system calls that maybe cause the network blocking,is cutted intodifferent sectors,and runs in the way of multitask. The results of experiments and feedbacks from actual applicationshow that the refined algorithm gets great improvement on the download efficiency and memory occupancy.
The TCSEC-based traditional development model of secure operating systems is exhibiting more and more obviously inability in the rapidly changing world of computer applications. With an experiment of building a secure operating system in accordance with the philosophy of the international standard for computer security evaluation,i. e.the Common Criteria,research on nontraditional development model of secure operating systems is conducted in this paper.
