 Describe characteristics common to all network operating systems (NOS)  Compare and evaluate NOSs to select the right one for your network  Define the requirements for and features of the Windows Server 2008 NOS  Define the requirements for and features of UNIX and Linux NOSs  Create users and groups and assign file permissions on systems running Windows Server 2008 and UNIX

 NOS – allows servers to share resources with clients  NOS characteristics  Manage network resources  Secure access to a network  Manage remote users  Allow users to connect to other networks  Backup and availability of data  Status and functionality  Update and patch management  Efficient server use  Fault tolerance

 To ensure that an administrator is effectively evaluating the particular situation for adding/installing a server, the following questions should be answered  What applications will be installed/ran on the server?  How many clients will be connected?  How much storage space?  How much down time is acceptable (if any)?  How much server can the organization afford?

 Client/server communication process is the same across all platforms  The user, at the client’s desktop enters credentials to gain access to the server (usually username and password)  A service on the client called a redirector intercepts the request and determines who is to handle the request  A redirector is a Presentation Layer service  Resides on both the client and server  If the redirector determines the request is for the client, it send the information to the client’s processor  If the redirector determines it is for the server or other network resource, it sends it to the network  This process is repeated anytime the client communicates with the server

 Clients  Macintosh  Windows  Linux  Middleware  Software necessary to translate request and responses between clients and server  Runs a separate service sometimes even on a different machine  Server

 User Account – An account that grants privileges based on the user and assigned group  Group – A collection of users that have the same restrictions/privileges  Administrator Account – An account that is created by default and grants all rights and privileges  Root – Name for the default administrator account created in UNIX or Linux  Hierarchically created groups (parent/child groups) will inherit the main group’s or top level group’s permissions

 Is a list that organizes resources and associates them with their characteristics  Lightweight Directory Access Protocol (LDAP) – used to access information stored in a directory  Object – a thing or person on the network  Attributes – properties associated to the object  Schema – the description of object types, or classes and their required and optional attributes  Classes (object classes) – type of object recognized by the NOS and defined by the schema; an example is printers and users  Organizational Units (OU) – logically defined receptacles that contain similar objects

 Directories and their contents form trees

 Shared applications are normally installed on a file server designed to run applications  Per User licensing – vendor sell only a fixed number of licenses that allows only that number of clients to use the application simultaneously  Per Seat – vendor sells a separate license for each potential user. This way the user is never denied access  Sharing Printers increases efficiency and reduces costs  Printers are connected via  Print server  Networked workstation  Direct network connection

 Memory  Physical Memory – refers to the RAM chips installed on the system  Virtual Memory – Space that is formed from hard drive and RAM memory  Page file  Swap file  If large hard drive using virtual memory is very efficient  May cost in terms of performance  Multitasking  The execution of multiple task at one time  Computers can only execute one task at a time because it has only one processor  The server allows one program to use the processor for a certain amount of time  Happens so quickly the user does not notice  Windows – Preemptive multitasking  UNIX – time sharing

 Multitasking  The execution of multiple task at one time  Computers can only execute one task at a time because it has only one processor  The server allows one program to use the processor for a certain amount of time  Happens so quickly the user does not notice  Windows – Preemptive multitasking  UNIX – time sharing

 The use of multiple processors from one machine (server)  Process – a routine of instructions that runs until it has achieved its goal  Thread – self-contained well-defined task within a process  Symmetric multiprocessing – splits all operations equally among 2 or more processors  Asymmetric multiprocessing – assigns each task to a specific processor

 Released Windows 2008 Server in February 2008  Replaced Windows Server 2003  Comes in several editions  Standard Edition – Provides basic resource and sharing features  Web Edition – Added services for web hosting, development, and application support  Enterprise Edition – Supports up to 8 processors for symmetric multiprocessing  Data Center Edition – Supports 64 processors, vitalization and is designed for high reliability and performance

 Supports multiple processors, multitasking and symmetric multiprocessing  Active Directory  Centralized management of multiple clients, resources, and services  Centralized management of all server functions through a single interface known as the Server Manager  Multiple, integrated web development and delivery services that support a high degree of security and an easy-to-use administrator interface  Supports modern protocols and security standards  Excellent integration with other NOSs and support from different client OSs  Integrated remote client services  Monitoring and improving server performance  Support for high-performance, large-scale storage devices

 Established by default  Expressly designed for the Windows NT platform  Secure, reliable compresses files for less storage space  Can handle massive files and fast access to data programs  Recommended for Windows Server 2008

 Support long-character file names (255 characters)  Stores file size information in 64 bit fields  Partitions can be up to 16 Exabyte’s  Required for Macintosh connectivity  Utilizes customizable compression routines  Maintains log files used for disaster recovery  Required for encryption, and advanced access security for files, user accounts, and processes  Improved fault tolerance through RAID and file redundancy

 The method of organizing and managing objects associated with the network in the Windows 2008 Server NOS  Can be setup 2 different ways  Workgroups Model  Group of interconnected computers that share each other’s resources without relying on a central server  Type of Peer-to-Peer network  Domain Model (Show domain graphic)  Type of client/server network that relies on domains instead of work groups  The databases that are used by domains to record their object and attributes are contained in the Active Directory  Domains are established to make it easier to manage resources and security on networks  The directory containing information in a domain reside on domain controllers  Member servers do not store directory information

 Domain tree – Organizes domains hierarchically  Base of the tree is considered the root  Child domains branch out from the root domain  Underneath the child domains organizational units branch out further and are called leaves  A collection of one or more domains is called forest  All domain trees in a forest share a common schema and can communicate with other domains, but only domains in the same tree share a common Active Directory database

 A trust relationship is where one domain allows another domain to authenticate its users  Active Directory supports 2 types of trust relationships  Two-way transitive trust (Use graphic fig 9-11 p 375)  Explicit one-way trust

 Naming conventions in Active Directory are based on LDAP naming conventions  Namespace is the complete database of hierarchical names used to map IP addresses to their host names  Each object on a Windows Server 2008 network can have 3 different names  Distinguished Name (DN) – long name that includes location within a tree’s containers and domains. The DN includes the:  Domain component (DC) – the names of the domains to which the objects belongs  Common name (CN) – name of the object  Relative Distinguished Name (RDN) – uniquely identifies an object inside a container normally same as the CN  User Principal Name (UPN) – the naming convention used in and othe Internet services. Example:  Logon name is phughes  UPN suffix

 Created by Ken Thompson and Dennis Ritchie from Bell Labs in the late 1960s  Was created to replace the cumbersome system that was in place  During the 1970s, antitrust laws made it possible for the UNIX system to be bought for a nominal licensing fee. The UNIX system from Bell Labs was named System V  Researchers at the University of Berkley at California enhance the UNIX software by adding useful tools such as TCP/IP subsystem and was known as BSD  Has several versions called flavors or distributions

 The ability to support multiple, simultaneously logged-on users  The ability to coordinate multiple, simultaneously running tasks  The ability to mount or make available on- demand disk partitions  The ability to apply permissions for file and directory access and modifications  Uniform method of delivering or receiving data from hardware devices, files, and running programs  The ability to start a program without interfering with a currently running program  Hundreds of subsystems  Source code portability  Window interfaces that the user can configure – most popular is X Windows system

 Proprietary UNIX – An implementation of UNIX source code that is not available or only available by purchase  Apple Computer – Mac OS X Server  Sun Microsystems – Solaris  IBM – AIX  Open Source UNIX – Freely distributed software not owned by any one company  GNU  Linux  Red Hat  Fedora  SUSE  Ubuntu  BSD

Solaris Hardware Requirements Linux Hardware Requirements

 Memory Model  Current UNIX and Linux systems use a 32-bit addressing scheme that allows programs to access 4GB of memory  These systems also run on CPUs that employ 64-bit addresses that allows programs to access 18 Exabyte’s of memory  Kernel  The core of a UNIX or Linux system  Kernel module is a file that contains instructions for performing a specific task such as reading or writing data to a hard drive  Solaris kernel is derived from the original AT&T UNIX software from Bell Labs  Linux kernel is derived from the software that Linus Torvalds wrote and released in 1991

 UNIX was the first system to use hierarchical file system  /boot – contains the kernel and other system initialization files  /bin and /sbin – applications and services are stored here  /var – holds variable data such as  Log files  Unread s  Print jobs  /home – holds user accounts

 Two categories  Disk File System  Used to organize, manage, and accessing files through local structures and software routines  Linux native system file is ext3  Solaris native system file is UNIX File System (UFS)  Network File Systems  Allows you to attach shared files from Windows or UNIX servers and share files with users on the other computers  Sun Microsystems use Network File System (NFS)  Samba – Included in most Solaris and Linux systems

◦ Command interpreter takes commands inputted through the keyboard and executes them ◦ Every UNIX and Linux system contains full documentation of UNIX commands  Named man pages (manual pages)  Describes each command’s function  Normally is in 9 sections

For more information on this lesson, See Chapter 9 in the text book or the Professor **All Slides and graphics were produced by Professor Patrick Hughes**