Guide to Networking Essentials Fifth Edition

1
Guide to Networking EssentialsFifth Edition

• Chapter 8
• Simple Network Operations

2
Objectives

• Explain the operation fundamentals of network
  operating systems
• Describe networking software components
• Describe the basic steps of network operating
  system installation
• Configure network services
• Explain network application installation and
  configuration concepts

3
Network Operating Systems

• Network operating system (NOS) OS with functions
  that facilitate network communication, allow
  computer resources sharing on a network, and
  provide access control to those resources
• Interface for users and applications to access
  the network and its resources
• Introduced during the mid-1980s
• Handle standalone computer activities as well as
  communication over the network
• E.g., Novell NetWare, Windows Server 2000/2003,
  UNIX, and Linux

4
Basic Functions of an Operating System

• OS coordinates interaction between software
  applications and computer hardware
• Most applications are written so that they can be
  used only with a particular OS family
• Two features necessary in a NOS
• Multitasking capability to support numerous
  processes at one time
• Time slicing occurs when the CPUs computing
  cycles are divided between more than one task
• Human inability to distinguish instances of this
  brief time period creates the illusion of
  multitasking
• Every contemporary OS includes these functions

5
Basic Functions of an Operating System (continued)

• Two types of multitasking
• Preemptive multitasking
• Cooperative multitasking
• A true high-performance NOS must be a preemptive
  multitasking system
• All contemporary operating systems are designed
  to use preemptive multitasking
• OSs include many NOS features
• Some of these features are still reserved for OSs
  designed to be installed on a server computer

6
Software Components of Networking

• NOS manages computers activities and provides a
  network environment
• Organizes hardware into an interactive whole
• Coordinates/controls functions of
  machines/peripherals
• Supports security and privacy (network and users)
• Controls access to resources (user
  authentication)
• Advertises/manages resources (centralized
  directory)
• Provide access to shared resources
• NOS components naming services, directory
  services, and client and server software

7
Naming Services

• On most networks, a name is necessary to identify
  and access resources of all kinds
• Humans recognize symbolic names more easily than
  numeric names
• Naming services translate symbolic names into
  corresponding network addresses
• This chapter explains the relationship between
  how Microsoft uses NetBIOS names and how the
  TCP/IP-based Domain Name System uses domain names

8
NetBIOS Names

• Names can be no longer than 15 characters
• Ending a name with prevents it from appearing
  in the NetBIOS browse list

9
NetBIOS Names (continued)
10
Universal Naming Convention

• Drive mapping process of associating a network
  storage resource with a local drive letter
• Windows and Linux (running Samba) OSs and most
  other modern NOSs recognize Universal Naming
  Convention (UNC) paths, a standard method for
  specifying network resources
• \\servername\sharename
• In UNC-aware applications and many command-line
  activities, a UNC path can be used instead of a
  drive letter to access a network resource

11
Domain Names and DNS

• DNS translates symbolic domain names into numeric
  IP addresses
• Permits users to access resources and services by
  using symbolic domain names on the Internet
• DNS server maintains a DB of computer name and IP
  address pairs
• At least one DNS server is maintained for a
  domain
• Domain named logical grouping of network
  resources
• E.g., course.com
• When a network request for www.course.com is
  made, the request is sent to the DNS server
  responsible for the course.com domain

12
Directory Services

• Directory service manages information about
  network services, resources, users, groups, and
  objects so that users can access resources and
  services by browsing or asking for them by type
• Manages and controls access to network resources
• Access control (stores info and performs checks)
• E.g., Windows Active Directory, Novells
  eDirectory
• Uses tree and forest metaphor to organize
  contents
• Patterned after X.500 directory service
• LDAP is far easier to implement
• Most Linux versions include NIS

13
Client Network Software

• Client network SW part of NOS installed on PCs
  that access network services or network resources
• Most important component is a redirector
• SW component operating at the OSI models layer 6
  that is found on both client and server NOSs
• Hides from users the complicated tasks involved
  in accessing network resources
• Designator aids in network resource interaction
• Keeps track of the drive letters assigned locally
  to remote or shared drives
• A shared drive is known as a share
• Client SW can refer to Internet access
  applications

14
Server Network Software

• Server SW can restrict access to resources by
  using access controls
• Also user/group management, logon
  authentication, network administration, fault
  tolerance

15
Server Network Software (continued)
16
Client and Server Capabilities

• Many NOSs (e.g., Windows Server 2003, XP, Vista)
  include client and server capabilities in both
  the server and desktop versions
• Generally, the desktop version of the NOS is not
  as powerful or robust as the server version
• Novell NetWare is strictly a server NOS, so
  theres no desktop version of NetWare
• In Linux, the choice between a desktop or server
  installation is usually made during installation

17
Installing a Network Operating System

• Installing an NOS is not much different than
  installing a standard desktop OS
• Requires only a few additional steps focused on
  configuring the network and the server services
• Before installation of an NOS can begin, however,
  you must complete a few preparatory steps

18
Installation Preparation

• Before you begin an NOS installation, you need to
  understand the following network aspects
• Size of the network
• Job requirements of the server
• Organization of storage devices
• File systems to be used
• Identification or naming convention
• Network adapter configuration
• Protocol selection
• Hardware compatibility

19
Size of the Network

• The size of a network can affect which services
  you decide to configure, how many servers you
  need, and the number of connection licenses you
  require
• A small LAN with fewer than 10 users who require
  only file and printer sharing can probably
  function fine with a peer-to-peer network
• Windows XP or Vista could serve as the OS
• With more users or more advanced networking
  service requirements, a dedicated server with an
  NOS designed for servers is definitely in order

20
Server Job Requirements

• The services and resources hosted by a server
  determine what components are installed
• E.g., DNS, DHCP, Web services, remote access,
  etc.
• Other server responsibilities
• Domain controller authenticates users and
  maintains directory services and the security DB
  for a domain
• For fault tolerance, install at least two per
  domain
• Member server hosts a service or resource and
  doesnt maintain the directory and security DB
• In NetWare, use existing tree or create new one
• In Linux, decide individual services to install

21
Storage Device Organization

• Crucial to networks success when accessibility,
  performance, and fault tolerance are essential
• Partition logical organization of disk space
  each partition appears as a separate logical
  drive
• Ways to organize NOS host drive
• Multiple-boot good for testing not good for
  security
• Single-partition, single-NOS most secure
• Multiple-partition, single-NOS useful for
  separating data from OS files increases drive
  activity
• Fault-tolerant storage e.g., disk mirroring, RAID

22
File Systems

• File system method used to store, organize, and
  manage access to files on a mass storage device
• File systems differ in how they allocate space,
  how files are located on disk, the level of fault
  tolerance, and how access to files is secured
• Fault-tolerant features include backup copies of
  FAT, journaling
• Folder- and/or file- level security are important
• E.g., as provided by NTFS or ext3
• Its best to use the most secure file system
  available for the OS youre installing

23
Naming Conventions

• Naming convention method of creating names
• Should have scheme for user accounts, computers,
  directories, network shares, printers, and
  servers
• Common naming schemes
• Construct user names from the users first and
  last names, plus a code identifying job title or
  department
• Construct group names from resource types,
  department names, location names, project names
• Construct computer names for servers and clients
  from their department, location, and an ID number
• Must be consistent, easy to use and understand,
  and must enable clear object identification

24
Network Adapter Configuration

• The NIC is the primary communication device
  between a computer and the rest of the network
• A computer purchased as a server already has an
  NIC installed
• Must verify manufacturer and model number to
  ensure compatibility and update device drivers as
  necessary
• Most NICs are plug-and-play-compatible with the
  OS, so NIC configuration isnt usually necessary
• Verify compatibility with the OS version you are
  using, and have a driver disk ready in case the
  OS doesnt recognize the NIC

25
Protocol Selection

• Protocol and configuration options must be
  compatible for computers to communicate
• For example, TCP/IP requires the following pieces
  of information before NOS installation begins
• IP address
• Subnet mask
• Default gateway
• DNS
• WINS
• DHCP

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Hardware Compatibility

• HW components of the computer on which its
  installed must be compatible with the NOS
• If you use incompatible hardware, the vendor
  might not provide technical support
• Double-check that your computers HW components
  are fully compatible with the NOS
• Microsoft publishes the Windows Catalog
• Formerly called the Hardware Compatibility List
  (HCL)
• Linux distributors publish a similar list for the
  various Linux versions
• Novell typically certifies whole systems as
  NetWare compatible

27
Installing Microsoft Windows Servers

• Windows server versions are not much more
  difficult to install than Windows XP or Vista
• With the proper preparation, the Setup Wizard
  makes the installation process as simple as
  entering a few key data items
• The major steps or sections of the installation
  included here give you insight into the
  architecture and simplicity of the Windows server
  line of operating systems

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Beginning the Installation
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Text-Based Phase
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GUI Phase

• In the GUI phase, you use a mouse or keyboard to
  enter items or make selections
• You define computer and domain names, enter the
  identification key from installation CD, select
  the server type (domain controller or member
  server), assign a password to Administrator
  account, select environment and desktop
  components
• Setup copies some files from the temporary folder
  to the destination folder and then moves into the
  network setup phase

31
Network Setup Phase

• You install drivers for the NIC, select and
  configure protocols, and review bindings
• Upon completion, files are copied to the system
  folder and temporary folder is deleted
• Next, you define time zone and display settings
• Then, the computer restarts, the Administrator
  logs on, and the Configure Server Wizard starts
• Allows the server to be configured as a domain
  controller, member server, or standalone server
• If server is to act as a domain controller,
  Active Directory is installed and configured

32
Installing Novell NetWare 6.5

• Install NetWare by using one of two methods
• Over the network
• From a CD
• The primary install utility is INSTALL.NLM
• Two phases
• Text mode
• Create partitions, accept license agreement, copy
  files, install storage device drivers, and select
  NIC drivers
• GUI mode
• Assign server name, set up protocols, and install
  eDirectory

33
Installing Linux
34
Installing Linux (continued)
35
Installing Linux (continued)
36
Configuring Network Services

• Network services, the basic resources on all
  networks, are the foundation of network
  applications
• The two most basic shared network resources
  (network services) are printers and file folders
• You can add numerous capabilities, resources, and
  delivery methods to a default NOS installation
• Groupware applications, e-mail packages, shared
  whiteboard applications, Web servers, etc.

37
Installing, Removing, and Configuring Network
Services
38
Network Bindings

• Binding process of linking network components
  from various levels of the network architecture
  to enable communication between those components
• Associate upper-layer services and protocols to
  lower-layer network adapter drivers
• Many NOSs enable all valid bindings by default
• Often results in some performance degradation
• Binding order should enhance the computers use
  of the network
• Bind the most frequently used protocol, service,
  or adapter first to speed network connections

39
Network Printing

• It is one of the two essential network services
• Redirector intercepts print requests and forwards
  them to the right print servers or network
  printers
• Three components the print server, the print
  queue, and the printer
• First, installing a printer on a server or as a
  direct network-connected device
• Next, share printers logical representation in
  NOS
• Print queue is a storage location that accepts
  print jobs from network clients and stores the
  print job until the printer is available to print
  it

40
Network Printing (continued)
41
Printer Management

• On most networks, you manage printers from local
  direct access or through the network printer
  share
• Sometimes you may use a Web browser (e.g., IPP)
• Must have right level of access granted to user
• Printer management covers wide range of
  activities
• Granting and restricting user access to printers
• Monitoring the print queue for proper functioning
• Limiting access (time frame, department, or
  priority)
• Updating local and remote printer drivers
• Maintaining printers
• Managing printers remotely

42
Sharing Fax Modems

• This feature is not often a default component in
  an NOS many third-party vendors offer add-on
  products to share a fax modem over a network
• With these add-on products, clients can fax
  documents from the desktop
• You can manage and administer fax shares just
  like printer shares
• Usually, additional client-installed software is
  needed to connect to a fax share
• After drivers are installed, theres no major
  difference between using a printer share and a
  fax share

43
File Shares
44
Network Applications

• Network applications designed for multiple
  simultaneous users on computers on a network
• Three types of essential network applications
  messaging, scheduling, and groupware
• Pros
• Much easier to administer (e.g., on large
  networks)
• Save money
• Cons
• Poor network performance degrades performance
• If network is down, application is often unusable

45
Network Applications (continued)

• At least three types of architectures for network
  applications
• Centralized
• File-system sharing
• True client/server

46
E-Mail or Messaging

• Most popular network application
• E-mail is fast and asynchronous
• Based on a common protocol and standards for
  communication
• Post Office Protocol version 3 (POP3)
• Simple Mail Transport Protocol (SMTP)
• Internet Message Access Protocol (IMAP)
• X.400
• X.500
• Message Handling System (MHS)

47
Scheduling or Calendaring

• A network scheduler is an electronic form of an
  appointment book and to-do lists
• Most offer private and public calendars,
  appointment books, task lists, and
  contact/address books
• They can also notify about upcoming meetings,
  warn about overlapped schedules, and offer
  reminders of special events or the need to
  contact someone
• Most offer integration into e-mail programs and
  office-productivity suites
• To supplement or replace a paper-based personal
  information manager, schedules can be printed

48
Groupware

• Groupware enables multiple users to interact with
  a single file, document, or project
• E.g., an entire department can contribute to a
  documents production and watch as the groupware
  combines everyones input into a single document
• Examples multiuser multimedia authoring tools,
  Lotus Notes, Novell Virtual Office, and HPs
  TeamLinks
• Some make it possible to collaborate across the
  Internet
• The biggest explosion in groupware products is
  integrating PDAs with corporate networks

49
Summary

• Network operating system (NOS) controls the
  operations of a computer, including local
  hardware activity as well as communication over
  network media
• Enables sharing resources, managing peripherals,
  maintaining security, and controlling user access
• Client network software on workstations allows
  users to take advantage of network resources
• Doesnt always mean redirectors and designators
• Server network software is designed to host
  resources so that multiple clients can access them

50
Summary (continued)

• Installing an NOS is similar to installing any OS
• Issues you must be aware of include size of the
  network, job requirements of the server, storage
  device organization, naming conventions, NIC and
  protocol selection and configuration, and
  hardware compatibility
• The steps for installing Windows Server
  2000/2003, Novell NetWare, and Linux are similar
• Two fundamental network services sharing
  printers and sharing files
• Some standalone applications have been revised to
  function as cross-network applications