Transcript Introduction to Windows NT/2000

Introduction to
Windows NT/2000
The operating System Zoo
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Mainframe Operating Systems –
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High-End Servers
Processes routine jobs without any interactive
user present
OS/390 for example
Server Operating Systems
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Run on Large PC or even on Mainframes
Print , file or web services
Unix , Windows 2000 , Linux
The operating System Zoo(2)
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Multiprocessor Operating Systems
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PC Operating Systems
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Windows 2000 (up to 32 CPUs) , SunOS
Running users applications
Multimedia support
Windows 98/Me/Xp
Real-Time Operating Systems
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Time as a key parameter (hard dead line)
VxWorks , QNX
The operating System Zoo(3)
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Embedded Operating Systems
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Run on a computer not generally thought of as
computer, like TV ,microwave etc.
Have some characteristics of real-time systems
PalmOS , Windows CE
Smart Card Operating Systems
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Very small - run on a credit card sized device
Some are Java Oriented (based on JVM)
History
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DOS 1 – 1980
Windows 3 – 1990
Windows NT – 1993
Windows 95 / 98 / Me
Windows 2000 Pro / Server / Advanced /DC
Windows XP Home/Pro - 2001
Windows.Net - 2003
Windows Family Roadmap
Home
PCs
Client
Windows
95 / 98
NTWS
Business
PCs
32 and 64 bit
Windows .Net Servers
NTServer
Servers
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Datacenter
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Advanced
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Small Business
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Standard
Windows 2000 Product Family
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Windows 2000 Professional
Windows 2000 Server
Windows 2000 Advanced Server
Windows 2000 Datacenter Server
Windows 2000 Professional
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Client version of the Windows 2000 product family
Designed to provide a stable, reliable, and fast
platform for end users to run their applications
A high-performance, secure-network client computer
and corporate desktop operating system that
incorporates the best business features of Microsoft
Windows 98 and builds on the traditional strengths
of Microsoft Windows NT Workstation
Windows 2000 Professional
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4 GB Memory
2 Processors
Windows 2000 Server
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A file, print, and application server, as well as a
Web-server platform, that contains all the features of
Windows 2000 Professional plus many new serverspecific functions
Terminal Services
For small- to medium-sized organizations
4 GB Memory
4 Processors
More Services and connectivity options
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Active Directory
Network Storage Management
Windows 2000 Advanced Server
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A more powerful departmental and application
server operating system that includes the full feature
set of Windows 2000 Server and adds the advanced
high availability and improved scalability required for
enterprise and larger departmental solutions
High end enterprise networks
2-node Clustering
Load Balancing
8 GB memory
8 Processors
Windows 2000 Datacenter Server
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A specialized high-end version of Windows 2000
Server designed for large-scale enterprise solutions
and optimized for large data warehouses,
econometric analysis, large-scale simulations in
science and engineering, online transaction
processing, and server consolidation projects
Large Database applications
64 GB memory
32 Processors
4-node - Clustering
Characteristics of Modern Operating
Systems
1. Microkernel architecture
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Assigns only a few essential functions to the
kernel
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address space
interprocess communication (IPC)
basic scheduling
Other functions run in user mode and treated like
any other application
Characteristics of Modern Operating
Systems
Multithreading
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process is divided into threads that can run
simultaneously
Thread
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dispatchable unit of work
executes sequentially and is interruptable
Process is a collection of one or more threads
Useful when there is no need to serialize, e.g.,
database that deals with several clients
Characteristics of Modern Operating
Systems
Symmetric multiprocessing
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there are multiple processors transparent to the user
these processors share same main memory and I/O facilities
All processors can perform the same functions
Better performance (speed), availability (fault tolerance), growth,
scaling (wide price range)
Multiprogramming vs. multiprocessing
Operating Systems Concepts
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Process
Memory management
Information protection & security
Scheduling and resource management
Network support
The Shell
2000 / NT Architecture
System Components — Kernel
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Foundation for the executive and the subsystems.
Never paged out of memory; execution is never preempted.
Four main responsibilities:
 thread scheduling
 interrupt and exception handling
 low-level processor synchronization
 recovery after a power failure
Kernel is object-oriented, uses two sets of objects.
 dispatcher objects control dispatching and synchronization
(events, mutants, mutexes, semaphores, threads and timers).
 control objects (asynchronous procedure calls, interrupts, power
notify, power status, process and profile objects.)
Kernel — Process and Threads
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The process has a virtual memory address
space, information (such as a base priority),
and an affinity for one or more processors.
Threads are the unit of execution scheduled
by the kernel’s dispatcher.
Each thread has its own state, including a
priority, processor affinity, and accounting
information.
A thread has a state: ready, running, waiting
etc.
Kernel — Scheduling
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The dispatcher uses a 32-level priority scheme to
determine the order of thread execution. Priorities
are divided into two classes..
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The real-time class contains threads with priorities ranging
from 16 to 31.
The variable class contains threads having priorities from 0
to 15.
Characteristics of NT priority strategy.
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Trends to give very good response times to interactive
threads that are using the mouse and windows.
Enables I/O-bound threads to keep the I/O devices busy.
Complete-bound threads soak up the spare CPU cycles in
the background.
Kernel — Scheduling (Cont.)
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Scheduling can occur when a thread enters
the ready or wait state, when a thread
terminates, or when an application changes a
thread’s priority or processor affinity.
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Real-time threads are given preferential
access to the CPU; but 2000 does not
guarantee that a real-time thread will start to
execute within any particular time limit. (This
is known as soft realtime.)
Executive
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Object Manager
Naming Objects
Virtual Memory Manager
Process Manager
Local Procedure Call Facility
I/O Manager
Plug-and-Play Manager
Virtual Memory Manager
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The design of the VM manager assumes that the
underlying hardware supports virtual to physical
mapping a paging mechanism, transparent cache
coherence on multiprocessor systems, and virtual
addressing aliasing.
The VM manager in NT uses a page-based
management scheme with a page size of 4 KB.
The NT VM manager uses a two step process to
allocate memory.
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The first step reserves a portion of the process’s address
space.
The second step commits the allocation by assigning space
in the NT paging file.
Volume and File Structure
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Sector , Track , Cylinder
Cluster
Partition - Volume - RAID
File System
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FAT16 – DOS , Windows95 , NT
FAT32 – Windows32/Me/2000/Xp
NTFS – WindowsNT/2000/Xp
File System
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File-Allocation Table
FAT
File System
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The fundamental structure of the NT file system (NTFS) is a
volume.
 Created by the NT disk administrator utility.
 Based on a logical disk partition.
 May occupy a portions of a disk, an entire disk, or span across
several disks.
All metadata, such as information about the volume, is stored in
a regular file.
NTFS uses clusters as the underlying unit of disk allocation.
 A cluster is a number of disk sectors that is a power of two.
 Because the cluster size is smaller than for the 16-bit FAT file
system, the amount of internal fragmentation is reduced.
File System — Internal Layout
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NTFS uses logical cluster numbers (LCNs) as disk addresses.
A file in NTFS is not a simple byte stream, as in MS-DOS or
UNIX, rather, it is a structured object consisting of attributes.
Every file in NTFS is described by one or more records in an
array stored in a special file called the Master File Table (MFT).
Each file on an NTFS volume has a unique ID called a file
reference.
 64-bit quantity that consists of a 48-bit file number and a 16-bit
sequence number.
 Can be used to perform internal consistency checks.
The NTFS name space is organized by a hierarchy of directories;
the index root contains the top level of the B+ tree.
File System — Recovery
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All file system data structure updates are performed
inside transactions that are logged.
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Before a data structure is altered, the transaction writes a
log record that contains redo and undo information.
After the data structure has been changed, a commit
record is written to the log to signify that the transaction
succeeded.
After a crash, the file system data structures can be
restored to a consistent state by processing the log
records.
File System — Security
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Security of an NTFS volume is derived from the
2000 object model.
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Each file object has a security descriptor attribute
stored in this MFT record.
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This attribute contains the access token of the
owner of the file, and an access control list that
states the access privileges that are granted to each
user that has access to the file.
Windows NT (2000) -NTFS
Networking
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Stand Alone
Domain – PDC , BDC
Network Environment
Microsoft
Networks
Netware
Windows NT
Macintosh
UNIX
Systems
Remote
Access
NDIS
NETBEUI
NWLink
TCP/IP
Network Device Interface Specification
Ethernet
Token Ring
FDDI
Protocols
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TCP/IP: Routable organization protocol to
connect Internet world
NWLink: IPX/SPX-compatible protocol to
connect Netware Server
AppleTalk: Service for Macintosh clients
DLC: Used to connect printer or SNA
mainframes
DHCP Service (1)
DHCP Database
IP Address 1
IP Address 2
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DHCP Server
IP Address 1
DHCP
Client
IP Address 2
DHCP Client
Non-DHCP Client
DHCP Service (2)
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Dynamic Host Configuration Protocol
Assigning IP to DHCP client Automatically
Centralize and Manage the allocation of
TCP/IP configuration information
The client receives a valid IP address
WINS Service (1)
WINS Server
WINS Client
Registration Request
USER3=210.65.182.24
USER3
IP inquire for
USER3
USER3=210.65.182.25
USER1
WINS Database
USER1 210.65.182.22
USER2 210.65.182.23
USER3 210.65.182.24
WINS Service (2)
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Windows Internet Name Service
Resolve the computer name to IP
address
Update the WINS database dynamically
DNS Service
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Domain Name Service
Distributed database providing a hierarchical
naming system for identifying hosts on the
Internet
Connect to Internet system using Internet
naming conventions
Maintain a consistent hierarchical naming
scheme across an organization
IIS Service
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Internet and Intranet
Internet Information Server
Publish resources and services on the
Internet on private intranet
Use HTTP, Gopher, FTP to provide
information
CSNW (1)
Shared
Resources
NT workstation
with CSNW
Netware Server
NT workstation
with CSNW
CSNW (2)
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Client Service for Netware
Connect to file and print resources
directly
Support Netware 2.x or later
GSNW (1)
Netware
Server
Windows Client
NT Server
with GSNW
Windows Client
GSNW (2)
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Gateway Service for Netware
Create non-dedicated gateway to Netware
resources
Avoid the license problem
Manage a simple network envirenment
Component Base
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DLL
COM
DCOM – COM+
.NET