The authentication process for a Windows operating system at the server level can also be configured to validate the identity of the person logging in at the Windows domain and Microsoft Active Directory Service levels as well. Certificates can be assigned to specific applications, databases and processes within a Windows sever-based architecture and operating system configuration (Vellalacheruvu, Kumar, 2011). Another significant difference between UNIX and Windows security is the definition of the security model itself. UNIX defines permissions to the file level using user name and password, and can also assign security levels of a given process as well (Takeuchi, Nakayama, 2006). In many UNIX operating system versions a UID and GID-based session will be started when a user logs in and attempts a specific application or system-level process. It is possible to add on additional security layers to these UID and GID sessions using Kerberos login authentication technologies and processes, in addition to investing in secured file system architectures as well (Takeuchi, Nakayama, 2006). All of these functional improvements to UNIX however come at a high price and tend to increase the low Total Cost of Ownership (TCO) this operating system provides. The UNIX security model is not as adept at managing security on objects, complex, multi-threaded processes and interlinked TCP/IP commands as well (Vellalacheruvu, Kumar, 2011). Like the many variations of UNIX, the Windows operating system architecture is continually going through a series of modifications and enhancements to become more secure. The Windows Active Directory architecture is designed to eliminate the need for inter-domain trust controllers and the complexities of security on the previous generation...

Instead the Active Directory uses authentication layering technologies and Kerberos algorithm to increase security resiliency, making the operating system more difficult to hack into.
Process Management

Both UNIX and Windows operating system architectures are multiprocessing, multi-threaded in that both support multiple processes or threads at the same time. Both are also designed to support multitasking, multiuser commands and environments, and multithreading of applications. The Windows architecture continues to promote Win32 and Win64 multithreading of applications for greater performance.

Configuring process management within each operating system is often done with utilities and on occasion with shell scripting. In Windows the majority of these functions are driven by graphical user interfaces (GUI). In UNIX however process management is often handled through shell scripts. As the UNIX architecture in general is not as flexible as the Microsoft one at integration, it is common to find shell scripts that are used for File Transfer Protocol (FTP) and TELNET sessions from one system to another. A shell script is shown below for transferring file.txt to a computer center via FTP command. These types of shell scripts are so pervasive enterprise software vendors use them for moving files from one location to another on UNIX-based servers their software runs on (Iyer, Lee, Venkatramen, Vesset, 2007).

Shell script for transferring a file to a computer center

#!/bin/sh

HOST='ftp.users.computingcenter.edu'

USER='yourid'

PASSWD='yourpw'

FILE='file.txt' ftp -n $HOST