在 APPLE 机上应用 BASIC 语言编写程序,有时会遇到一些问题,如更改程序的部分或全部行号;把两个程序合并成一个程序;为解决 APPLE 机内存小的问题而把一个程序分成几块程序链接运行等。以上问题只要充分开发利用 DOS 3.3盘中的RENUMBER...在 APPLE 机上应用 BASIC 语言编写程序,有时会遇到一些问题,如更改程序的部分或全部行号;把两个程序合并成一个程序;为解决 APPLE 机内存小的问题而把一个程序分成几块程序链接运行等。以上问题只要充分开发利用 DOS 3.3盘中的RENUMBER 及 CHAIN 程序,就可迎刃而解。下面将分别详细介绍这两个程序的使用方法。展开更多
软件定义网络(software defined networking,SDN)已经迅速成为一种新的网络通信管理模式,极大地改变了传统网络架构.SDN可以通过将控制层与数据层分离来实现更细粒度的网络控制与管理.但是,转控分离的SDN架构也使得控制器极易成为DoS攻...软件定义网络(software defined networking,SDN)已经迅速成为一种新的网络通信管理模式,极大地改变了传统网络架构.SDN可以通过将控制层与数据层分离来实现更细粒度的网络控制与管理.但是,转控分离的SDN架构也使得控制器极易成为DoS攻击的目标.为解决这一问题,现对SDN中的DoS攻击进行全面的研究,并提出一种轻量有效的MinDoS防御机制,该机制主要由简化的DoS攻击探测模块和优先级管理模块这2个核心模块实现.该机制可以根据用户信任值将流请求分类并将其划分到具有不同优先级的多个缓冲队列,然后使用SDN控制器以双轮询机制来调度处理这些流请求,从而在DoS攻击下更好地保护控制器.另外,MinDoS还结合了多控制器动态调度策略来降低全局响应时间,提高用户服务质量.最后,分别在SDN单控制器和多控制器实验环境中对MinDoS防御性能进行综合评估,实验结果表明:MinDoS防御效果良好,系统设计满足预期目标.展开更多
For years, rumors have circulated that the code for the original DOS operating system created by Microsoft for the IBM personal computer is actually copied from the CP/M operating system developed by Digital Research ...For years, rumors have circulated that the code for the original DOS operating system created by Microsoft for the IBM personal computer is actually copied from the CP/M operating system developed by Digital Research Incorporated. In this paper, scientifically tested and accepted forensic analysis mathematical techniques, step-by-step processes, and advanced software code comparison tools are used to compare early versions of the two code bases. The conclusion is reached that no copying of code takes place1.展开更多
In a previous paper [1], I compared DOS from Microsoft and CP/M from Digital Research Inc. (DRI) to determine whether the original DOS source code had been copied from CP/M source code as had been rumored for many yea...In a previous paper [1], I compared DOS from Microsoft and CP/M from Digital Research Inc. (DRI) to determine whether the original DOS source code had been copied from CP/M source code as had been rumored for many years [2] [3]. At the time, the source code for CP/M was publicly available but the source code for DOS was not. My comparison was limited to the comparison of the DOS 1.11 binary code and the source code for CP/M 2.0 from 1981. Since that time, the Computer History Museum in Mountain View, California received the source code for DOS 2.0 from Microsoft and was given permission to make it public. The museum also received the source code for DOS 1.1 from Tim Paterson, the developer who was originally contracted by Microsoft to write DOS. In this paper, I perform a further analysis using the newly accessible source code and determine that no code was copied. I further conclude that the commands were not copied but that a substantial number of the system calls were copied.展开更多
文摘在 APPLE 机上应用 BASIC 语言编写程序,有时会遇到一些问题,如更改程序的部分或全部行号;把两个程序合并成一个程序;为解决 APPLE 机内存小的问题而把一个程序分成几块程序链接运行等。以上问题只要充分开发利用 DOS 3.3盘中的RENUMBER 及 CHAIN 程序,就可迎刃而解。下面将分别详细介绍这两个程序的使用方法。
文摘软件定义网络(software defined networking,SDN)已经迅速成为一种新的网络通信管理模式,极大地改变了传统网络架构.SDN可以通过将控制层与数据层分离来实现更细粒度的网络控制与管理.但是,转控分离的SDN架构也使得控制器极易成为DoS攻击的目标.为解决这一问题,现对SDN中的DoS攻击进行全面的研究,并提出一种轻量有效的MinDoS防御机制,该机制主要由简化的DoS攻击探测模块和优先级管理模块这2个核心模块实现.该机制可以根据用户信任值将流请求分类并将其划分到具有不同优先级的多个缓冲队列,然后使用SDN控制器以双轮询机制来调度处理这些流请求,从而在DoS攻击下更好地保护控制器.另外,MinDoS还结合了多控制器动态调度策略来降低全局响应时间,提高用户服务质量.最后,分别在SDN单控制器和多控制器实验环境中对MinDoS防御性能进行综合评估,实验结果表明:MinDoS防御效果良好,系统设计满足预期目标.
文摘For years, rumors have circulated that the code for the original DOS operating system created by Microsoft for the IBM personal computer is actually copied from the CP/M operating system developed by Digital Research Incorporated. In this paper, scientifically tested and accepted forensic analysis mathematical techniques, step-by-step processes, and advanced software code comparison tools are used to compare early versions of the two code bases. The conclusion is reached that no copying of code takes place1.
文摘In a previous paper [1], I compared DOS from Microsoft and CP/M from Digital Research Inc. (DRI) to determine whether the original DOS source code had been copied from CP/M source code as had been rumored for many years [2] [3]. At the time, the source code for CP/M was publicly available but the source code for DOS was not. My comparison was limited to the comparison of the DOS 1.11 binary code and the source code for CP/M 2.0 from 1981. Since that time, the Computer History Museum in Mountain View, California received the source code for DOS 2.0 from Microsoft and was given permission to make it public. The museum also received the source code for DOS 1.1 from Tim Paterson, the developer who was originally contracted by Microsoft to write DOS. In this paper, I perform a further analysis using the newly accessible source code and determine that no code was copied. I further conclude that the commands were not copied but that a substantial number of the system calls were copied.