A website that is using the proprietary Microsoft technologies can choose a web hosting company that uses a Windows NT server to host the website. To expand its web technology presence in 1993, Microsoft started to roll out its operating system support for web hosting. These families of 32-bit operating systems fall under the umbrella name Windows NT for New Technology. The Windows NT that is marketed for desktop edition is called Windows NT and the one that is used for web hosting web servers is called Windows NT Server. Just like its competitor's web hosting operating systems which is usually a Unix, the Microsoft designed Windows NT to have the following advanced features:
• a robust and self-healing file system called NTFS
• supports RISC CPUs aside from the traditional CISC
• the Windows NT kernel can work up to 32 CPUs
• a Hardware abstraction layer separates the hardware from software
• an Object Manager that arbitrates software communication inside the OS
• a Process Manager that coordinates several processes simultaneously
• a Virtual Memory Manager that expands the actual amount of RAM
• a process communication support called Local Procedure Call
• a better I/O Manager for data read and write to pheripherals
• a Security Reference monitor (SRM) for data integrity
• a Preemptive Multitasking behavior that takes the highest priority task first
• a better networking communication Interprocess Communication (IPC) using DCOM
As a server operating system, the Windows NT NTFS file system has been designed to be tolerant and robust and has security built from the beginning. This is unlike the older FAT file system of the MS-DOS. However, Windows NT is also backward compatible and works with the older FAT file system.
Windows NT also supports the HPFS file system. This is a fast file system, because it keeps several information in RAM memory in a form of a cache and only does a write to the physical disk at certain times when the cache is almost full or when there's an explicit flush. The speed of thes particular file system is compensated by its decrease in reliability for example during a sudden power failure and the information that is still in the cache is forever lost.
Nevertheless, Windows NT has the best of both worlds in terms of its support for HPFS and FAT. In contrast to HPFS, FAT is a slower but a more reliable file system during sudden power failure as it writes the information to the disk right away. Caching is also a feature of NTFS and in addition it also keeps a log that can be used to restore the file system to a working state in case of a power failure.
Microsoft also provided a Windows NT to run on RISC processors (MIPS, PowerPC, DEC Alpha) in addition to its traditional support on CISC processor in the intel x86 architectures.
Windows NT for the desktop is not exactly the same as the Windows NT server. The latter can run on 32 processors and this is a significantly faster system since multiple processes are delegated to a separate CPUs.
The Windows NT kernel interacts with a software layer called the HAL. The HAL is the layer that directly communicats to the processors. The HAL layer makes the Windows NT run on many different processors.
The object manager in Windows NT is the subsystem that arbitrates proper channel and communication to different various resources which are abstracted as objects.
Windows NT can run several processes at a time and the process manager is the subsystem that protects threads and process addresses. This makes several applications and services available.
Windows NT can actually support more memory than it actually has throught the Virtual Memory Manager. The portions of memory in RAM that are not currently used is written into the hard disk to free up some RAM needed for other programs to be able to run. When this memory is needed back, the data is read from hard disk and gets loaded into RAM by the Virtual Memory Manager.
Several processes within the Windows NT can communicate to each other using message-based messaging which results to procedure calls invoked locally (LPC).
The Windows NT's I/O manager is used to manage I/O data communications between thet operating system kernel to the peripheral devices such as the physical disk, network cards etc, through the device drivers of these devices.
Windows NT also has a fine-grained object-based security via SRM. The operating system intervenes each object accessed operations and ensures proper security authentications.
Preemptive Multitasking in Windows NT guarantees that processes with the highest priority gets the CPU's attention by suspending current processes with lower priorities. When the high priority process completes, the lower priority processes continues to run.
Windows NT supports client/server network communication model as its interprocess communication. Important events happening within the system sents out a windows message to processes for notification. One such high-level implementation of this IPC communication is through Distributed Component Objcet Model (DCOM) which is used to communicate with other computers.
