Study theme 8: Network Operating Systems and Windows NT based Networking

1
Study theme 8 Network Operating Systems and
Windows NT based Networking
2
Study Theme Objectives

• Define the requirements and characteristics of a
  Windows NT network environment
• Describe how a Windows NT server fits into an
  enterprise-wide network
• Perform a simple Windows NT Server installation
• Manage users, groups, and rights under Windows NT
  Server
• Understand how Windows NT Server integrates with
  other network operating systems
• Discuss the elements of a network operating system

3
Introduction to Network Operating Systems

• Selecting a network operating system
• Is it compatible with existing infrastructure?
• Will it provide the security required by the
  networks resources?
• Can the technical staff manage it effectively?
• Will existing applications run smoothly on it?

4
Introduction to Network Operating Systems

• Selecting a network operating system (cont.)
• Will it accommodate future growth (that is, is it
  scalable)?
• Does it support additional services the networks
  users require?
• How much does it cost?
• What type of sort can be expected from the vendor?

5
Network Operating Systemsand Servers

• How many clients will connect to the server?
• What kind of applications will run on the server?
• How much storage space will each user need?
• How much down time is acceptable?
• What can the organization afford?

6
Multiprocessing

• Technique of splitting tasks among multiple
  processors to expedite the completion of any
  single instruction
• Symmetric multiprocessing
• Splits all operations equally among two
  processors
• Supported by Windows NT Server
• Asymmetric multiprocessing
• Assigns each subtask to a specific processor

7
Introduction to Windows NT Server

• Windows NT Server is a popular network operating
  system known for its intuitive graphical user
  interface(GUI)
• Pictorial representation of computer functions
  and elements that, in the case of network
  operating systems, enables administrators to more
  easily manage files, users, groups, security,
  printers, and other issues

8
Advantages to Windows NT Server

• Windows NT supports any type of topology or
  protocol normally run on a LAN
• Efficient operating system uses multiple
  processors and employs multitasking to allow
  processes on the server to share CPU resources
• Easy to manage and well supported

9
Drawbacks to Windows NT Server

• Does not natively provide support for remote
  administration
• Requires significant administrative effort to
  scale this operating system to a very large
  enterprise
• Requires a server restart after any significant
  system change

10
A Closer Look at the Windows NT Operating System

• Windows NT Servers Memory Model
• Physical memory
• Chips installed on the computers system board
  that provide dedicated memory to that computer
• Virtual memory
• Memory that is logically carved out of space on
  the hard disk

11
File Systems and CDFS

• File System
• An operating systems method of organizing,
  managing, and accessing its files through logical
  structures and software routines
• CDFS (CD-ROM File System)
• Read-only file system used to access resources on
  a CD-ROM disk

12
FAT(File Allocation Table)

• Original PC file system designed in the 1970s to
  support floppy disks and, later, hard disks
• FAT partition or file cannot exceed 4 GB
• FAT uses 16-bit fields to store file size
  information
• FAT supports only filenames with a maximum of
  eight characters in the name and three in the
  extension
• FAT categorizes files on a disk as Read, Write,
  System, or Hidden

13
FAT(File Allocation Table)

• Directories and files on a FAT drive cannot use
  Windows NTs security
• A FAT drive stores data in noncontiguous blocks
  and uses links between fragments to maintain data
  integrity
• You can convert a FAT drive into an NTFS drive on
  a Windows NT server, but you cannot convert an
  NTFS drive into a FAT drive
• Because of FATs low overhead, it can write data
  to a hard disk very quickly

14
FAT32 andHPFS

• FAT32
• Enhanced version of FAT that accommodates the use
  of long filenames and smaller allocations units
  on a disk
• HPFS (High-Performance File System)
• Designed for OS/2 operating system that offers
  greater efficiency and reliability than FAT
• Supports extended attributes
• Attributes beyond basic Read, Write, System, and
  Hidden attributes supported by FAT

15
NTFS(New Technology File System)

• Developed expressly for Windows NT Workstation
  and Windows NT Server
• Filename can be maximum of 256 characters long
• Stores file size information in 64-bit fields
• Files or partitions can be as large as 16
  exabytes
• Required for Macintosh connectivity
• Incorporates sophisticated, customizable
  compression routines
• Keeps a log of file system activity to facilitate
  recovery if a system crash occurs

16
Windows NT Domains

• Domain
• Group of users, servers, and other resources that
  share account and security information
• A Primary domain controller (PDC)
• Centrally manages account information and
  security
• A Backup domain controller (BDC)
• Backs up the PDC

17
Windows NT Domains

• Promote
• Microsoft term
• To grant a higher authority to a server
• Member server (MS)
• Takes no responsibility for managing accounts or
  security
• Dedicated to running a particular application
  that requires dedicated processing resources

18
Trust Relationships

• Relationship between domains that make it
  possible for users in one domain to access
  resources in another domain
• One-way domain trust relationship
• Established when one domain allows users in
  another to access its resources

FIGURE 8-3 One-way domain trust relationship
19
Trust Relationships
FIGURE 8-4 Multiple one-way domain trust
relationships
20
Trust Relationships

• Two-way domain trust relationship
• Two domains allow each other access to their
  resources

FIGURE 8-5 Two-way domain trust relationship
21
Domain Models

• Single domain model
• Simplest Windows NT domain model
• One domain that services every user and resource

FIGURE 8-6 Single domain model
22
Domain Models

• Master domain model
• Uses a single domain to exert control over user
  account information
• Separate resource domains manage resources such
  as networked printers

FIGURE 8-7 Master domain model
23
Domain Models

• Multiple master domain model
• Uses two or master domains that are joined in
  two-way trusts to manage many resource domains

FIGURE 8-8 Multiple master domain model
24
Domain Models

• Complete trust domain model
• Administration is completely decentralized
• Each domain manages its own user

FIGURE 8-9 Complete trust domain model
25
Coordinating Multiple Servers

• Browser
• Network computer that tracks location,
  availability, and identity of shared resources
• A domain master browser tracks resources for a
  group of domains
• A master browser maintains a databasecalled a
  browse listof shared resources for its domain
• A backup browser keeps a copy of the master
  browsers browse list in case the master browser
  goes down

26
Coordinating Multiple Servers
FIGURE 8-10 Browser in a master domain model
network
27
Synchronization

• Process undertaken by a PDC and its BDCs to keep
  identical user account information in both of
  their user databases
• Partial synchronization
• Only modifications to user account information
  are transmitted between domain controllers in a
  domain
• Full synchronization
• Entire user account database is relayed from the
  PDC to its BDCs

28
Elections

• Browser election
• Vote between computers to determine which one
  will take over responsibility for maintaining the
  master browse list

29
Installing and Configuring a Windows NT Server

• Planning for installation
• Will the server be a PDC, BDC, or member
  (standalone) server?
• To which domain will the server belong?
• What will the servers name be?
• How many and what kinds of network adapter cards
  will the server use?

30
Planning for Installation

• Which protocols and networks services should the
  server use?
• What kind of disk controllers does the server
  have?
• How many, how large, and what kind of partitions
  will the server require?
• Will the server support additional services?
• In an express setup, the most popular
  installation options are chosen for you
• In a custom setup, its possible to determine
  which services and programs are installed

31
Planning for Installation

• Which licensing mode should be chosen?
• The per server licensing mode allows a limited
  number of clients to access the server
  simultaneously
• The per seat mode requires licenses for every
  client capable of connecting to the Windows NT
  server
• How can all this information be remembered?
• Emergency repair disk
• Disk used to restore a Windows NT server to its
  previous, working hardware configuration if its
  configuration becomes irreparably botched

32
Establishing Users, Groups, and Rights

• Users with similar needs and restrictions can be
  combined into groups to more easily manage their
  access

TABLE 8-2 Providing security through groups
33
Groups

• Global group
• Group of users and resources that belong to
  multiple domains
• Local group
• Group of users and resources that belong to one
  domain

FIGURE 8-13 New Global group window
34
Internetworking with Other Network Operating
Systems

• Client redirector
• Software required for a client to access a server
  over the network
• Gateway Services for NetWare (GSNW)
• Acts as a translator between the different client
  redirector services