 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
|
Islam and Internet
ALAM Maritime
MISC Malaysia
What is Internet
American People
Rotterdam
50 States
Provinces of Canada
Palm Tree
TCP IP
Concept of Network
Specialized Servers
Workstaion Vs Server
Quraan in English
Dr Israr Ahmad
Poetry
Introducing NT
NT Protocols
Win NT Services
The Islands
Cool Links
Islamabad
|
|
| INTRODUCING NT |
 |
| Microsoft Series of Operating Systems |
| ||||||
| For Testpapers and Other Cources: http://www.ittutor.com http://www.cit.ac.nz/smac/cscourse.htm ____________________________________________________________ Chapter 1: One of the requirements for the Microsoft exam is to understand when to implement NT Workstation, NT Server or Windows 95. The key features of each operating system appears below. Windows 95/98 would be considered the best operating system for users of portable computers, in particular, support for plug and play and low system requirements make it ideal for this environment. For the home market once again 95/98 allow most legacy software programs to work on the system even if this involves booting in DOS mode. ____________________________________________________________ Chapter 2: Windows NT workstation offers platform stability. The operating system runs on two rings of the Intel chip called Kernel mode and User mode. In Kernel mode only the operating system itself is allowed to run. In this mode direct access to the hardware is allowed, and the failure of a software component in Kernel mode can cause the system to crash. Clearly the less code there is running in Kernel mode more robust the operating system is going to be to failure. Operating systems with the minimum amount of code running in the Kernel are called micro kernel operating systems. Whilst these are very robust they are also very slow. Every change from User mode to Kernel mode requires a processor switch which is CPU intensive. ____________________________________________________________ Chapter 3: Microsoft NT uses a modified micro kernel, or macro kernel. This means some parts of the operating system run in the kernel to benefit from the speed improvements gained from running in ring 0, whilst accepting the risks involved if these components fail. One of the big changes from NT 3.51 to NT 4.0 was the decision to allow the graphics subsystem to run in the Kernel. This meant the display runs a lot faster, fast enough even for games, yet the drivers for the screen, if badly written can crash NT. It has been argued that if the screen crashes is their any advantage to having the subsystem continue to run unaffected, in the case of a desktop, probably not. But in the case of NT server it may have been considered acceptable to allow network users to continue using the OS until the end of the day even thought the display had crashed. It is worth noting that drivers for other devices such as network cards have always run in the Kernel, so there are key components of the operating system running in privileged mode that were not written by Microsoft. In the case of crashes on you NT machine try removing these third party drivers. ____________________________________________________________ Chapter 4: NT Workstation also offers user level security. A database of accounts information is stored on the machine with user and password information for all clients. This database is implemented through a mandatory logon which means you cannot gain access to NT without supplying a good username and password. Another great design feature of NT from its conception was the implementation of a hardware abstraction layer. The HAL allows the operating system to make low level calls without reference to the underlying hardware. In practice this means a hardware manufacturer could modify the HAL to allow NT to work on a modified system. ____________________________________________________________ Windows 95: Low hardware requirements 4MB Ram minimum Maximum compatibility with legacy hardware Maximum compatibility with legacy software Share level security, security implemented on the use of a resource. ____________________________________________________________ Windows NT Workstation Higher hardware requirements 12 MB Ram Operating system more reliable, does not allow direct access to hardware for software or device drivers. Less compatibility with older software and hardware Ideal for small workgroups No centralised administration of accounts resources User level security as well as share level 10 user connections maximum ____________________________________________________________ Windows NT Server Higher hardware requirements 16MB Ram Operating system more reliable, does not allow direct access to hardware for software or device drivers. Less compatibility with older software and hardware Allows centralised administration of accounts databases through domain structures Very scalable supporting hundreds of users connections Accounts databases of around 40,000 users per domain More robust through RAID support Platform supports Microsoft Backoffice family ____________________________________________________________ |
| Islamabad, Pakistan |
|
. |
| Visitors: 01092 |