Homework 3.2

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Homework 3.2
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Clients
Hub
Using 100TX
Hub
Clients
Hub
Hub
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Client and Server Systems

• Operating Systems
• Windows 95/98
• Windows NT Workstation
• Windows NT Server
• Centralized Security and system policies
• Telecommunications
• Fax, mail, web

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Network Servers

• Network Operating Systems
• Timesharing splitting time between jobs
• Multitasking processing more that one job at a
  time
• Parallel Processing more than one cpu processing
  jobs
• Load Balancing sending jobs to different servers

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Multitasking

• Preemptive
• OS can take over a task without cooperation of
  the task.
• Nonpreemptive
• The task decides if it will give up the
  processor.

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Dedicated vs. Nondedicated

• Dedicated Server
• Server does server tasks only, it does not
  execute local programs (Novell)
• CPU time is dedicated to server operations
• Non Dedicated Server
• The user has an interface to the OS on the server
  and can execute programs locally (Linux,
  Microsoft)

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Software Components

• Client
• File access, Printing, Database access
• Server
• Disks, Printers, Programs
• Redirectors
• Handles client requests
• Forwards a local request to LPT1 to print server
• Accesses non local drive letters F\gt, G\gt, etc

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Server Software

• Resource Sharing
• File access remote access to servers disks
• Printer access remote requests to local printer
• Security and control
• Which users can access the disk or printer?
• Which users can write to the disk?
• File locking when 2 users want to write to the
  same file.
• Account for disk usage and printer paper

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Server Administration

• Managing Users
• Privileges
• Access to resources
• Passwords
• Location of users (address, email, etc.)
• Time limits (800 AM to 500 PM)
• Station limits (specific MAC address)
• Resource load balancing

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Novell Operating Systems

• NetWare
• NDS (Novell Directory Services)
• Disk caching and distribution among servers
• NDPS (Novell Distributed Printing Services)
• Web Servers
• Mail Services
• Calendaring/Scheduling
• Messenger service
• Routing

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Novell File Services

• Logon Security
• Authentication
• Trustee Rights
• Who can access what file/directory and what can
  they do with the file
• Directory attributes
• The types of operations on a file (read, write,
  shareable, copyable)

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Novell Distributed Printing Services

• Print spooling and control
• Access by users to specific printers
• Print load is transferred from client to server
• Printer messages (out of paper, change form) are
  displayed on the server console.
• Server handles multivendor printing protocols so
  client doesnt need to.
• Clients can share their printer through the server

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Microsoft Network Operating Systems

• Windows NT (includes Win2000, XP)
• Single domain, single server, small workgroup
• Single master, single server, multiple workgroups
• Multiple master, multiple servers, several
  workgroups, accounts on multiple servers
• Complete Trust
• Several domains no master (workgroups trust each
  other)

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Windows NT Services

• File services
• Similar to Novell, access, control, rights
• Security, server maintains access lists
• Printing
• Clients or servers can share their local printers
• Routing and Remote access
• Other services
• Messenger, Alerter, Browser

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Interoperability

• Gateway Services for NetWare
• Handles NetWare requests for a domain
• Client Services for NetWare
• Handles NetWare requests for a workstation
• File and Print Services for NetWare
• Protocol converter
• Directory Service Manager for NetWare
• Allows Windows clients to access NDS
• Services for Macintosh
• Allows Appletalk service on the NT server

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Appletalk Networks

• Appleshare
• Apple disk and printer sharing (Apple has its
  own file formats)
• Zones (Apples workgroups/domains)
• Security (each client maintains its own lists)
• Appletalk servers can handle multiple protocols
  (TCP/IP, Appletalk, Microsoft)

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UNIX (and Linux) Networks

• Simple Client only to Server transformation
• Can handle multiple protocols and services
  (Apple, Microsoft SMB, NFS)
• Can be configured as a router/firewall
• Well adapted to remote access

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Peer to Peer

• Simple to set up (almost all OSs have built in
  peer to peer support)
• Access lists are kept on each computer, there is
  no master server.
• Useful for small (10 or less) workstations
• Somewhat insecure

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Interoperability

• Multivendor environments
• Servers can support different OS clients
• Files transferred from different server types go
  through the client
• Files transferred from different client OSs go
  through the server
• File formats may be different on each vendors
  operating system. File type conversion can be
  done on the server or client.
• Authentication is almost always different between
  vendors.
• Network Protocols may also be different between
  vendors

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Server Security

• Warnings
• When a server is placed on the network it is now
  wide open for attack.
• All Network Operating Systems have bugs and
  security holes.
• Always upgrade to the latest revisions of the OS
• Limit the number of services provided by the
  server to the minimum needed for your particular
  application
• Use firewalls as needed in the local area network

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Network Types

• What Protocol to use?
• IPX
• TCP/IP
• Netbeui
• Which Name Service?
• DNS
• WINS
• LMHOSTS

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Windows NT/95/98/2K Client

• Pick a name (15 characters NetBios limit)
• Or use WINS
• Pick a workgroup or domain
• Get networking working
• Add appropriate protocols
• Edit LMHOSTS (for TCP/IP)
• Use Network Neighborhood or Find Computer to find
  the server

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Workgroup/Domain

• Workgroup
• Login is on each client
• Simple, minimal security
• No dedicated server
• Domain
• Login is to the server over the network
• Requires an NT Domain Server
• High security, centralized usernames/passwords

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Accessing Server Resources

• Nbtstat to check netbios connectivity
• UNC
• universal naming convention
• \\ntserver\users
• \\ntserver\laser_office
• net use
• net use j \\opie\bobw
• net use lpt1 \\ntserver\laser_office

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Web Services

• Web Server (IIS on NT based systems)
• Security Issues
• File access
• Database access
• CGI programs
• Counters
• Data Entry

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Mail Services

• SMTP Support
• POP and IMAP mail support
• Novell Groupwise
• Calendaring
• Scheduling
• Microsoft Exchange
• Calendaring
• Scheduling

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Other Services

• DATABASE Support
• Microsoft SQL Support
• Oracle Support
• MySQL Support
• Distributed License Service
• Accounting of server and resource use
• Disk space
• Pages printed