Transcript Chapter 7 LAN Operating Systems

Chapter 7
LAN Operating Systems
• LAN Software
• Software Compatibility
• Network Operating System (NOP)
Architecture
• NOP Functions
• NOP Trends
LAN Software
• Network operating systems
– Interface between hardware and application
software
• Application software: client front ends and
server back ends or engines
– Productivity software: e-mail, groupware etc.
– Resource management software: security &
monitoring
Vertical Software Compatibility
• Common compatibility protocol
• Types
– Server: hardware drivers, OS, network
operating system, DBMS, application backends, e-mail, groupware, distributed processing
– Client: hardware drivers, OS, network
operating system, database front-end, query
tools, application tools, groupware, other
network applications, distributed processing
front-end, user interfaces
Horizontal Software Compatibility
• Transparency between similar software
layers between different client and servers
• Use middleware
–
–
–
–
Database middleware
Network operating system middleware
Operating system middleware
Distributed application middleware
NOP Architectures
• Peer-to-peer
• Client/server
• Current client/server
Peer-to-Peer NOSs
• Traditional NOSs: LANtastic or PowerLAN
• Printing & file sharing for less than 50 users
• Workstation as service requester (client)
and/or service provider (server
• Lacking interoperability and scalability
Client/server NOSs
• Client software and server software:
Netware3.12 and Microsoft LANManager
• Scalability, fast, reliability
• Lacking interoperability
Current Trend of NOSs
• Client NOSs: universal client
• Server NOSs have performance characteristics
– NetWare for file and printing servers
– Windows NT, OS/2, UNIX for application servers
• Small business NOSs
– High-quality file and printing sharing service
– DOS based, with minimal memory and disk
requirement
– Easy installation, configuration, and management
– Dedicated 32-bit server software
– Bundled workgroup software (chat, e-mail)
– Easy migration to server-based NOSs
Client NOS
• Windows 95, OS/2 Warp Connect,
Windows NT Workstation
• Functions
– Operating system capabilities
– Peer-to-peer networking capabilities
– Client software to communicate with different
server network operating systems
Client NOS - OS Capabilities
• Desired characteristics
–
–
–
–
–
32-bit OS
Preemptive multitasking
Protect memory space
Symmetrical multiprocessing (SMP)
Multithreading
• User interface: object-oriented, windows
Client NOS - OS Capabilities
• Application program support
– Backward compatibility or legacy applications
(16-bit)
– 32-bit applications
• Plug-n-play (PnP) features
– PnP devices
– PnP drivers
– Reconfiguration
Client NOS - Peer-to-Peer
Networking Capabilities
• File and printer sharing
• Workgroup application
Client NOS - Networking
Capabilities
•
•
•
•
Multiple servers
Transfer protocols
Remote access
Laptop synchronization (with desktop)
–
–
–
–
–
Copy by date option: date range
Bidirectional option
Cloning option
Refresh option: existing files
Delta file synchronization: changes
Client NOS -Analysis
• Hardware/platform
– Required-recommended memory
– 16 or 32 bit
– User interface
• Operating system capabilities
• Peer-to-peer networking capabilities
• Client networking capabilities
Sever NOSs - Types
•
•
•
•
•
UNIX
TCP/IP
NFS
NetWare
Windows NT
UNIX
• Portability
– Hardware platform
– Application programs
• Modularity
TCP/IP
• Internet suite of protocols
• De facto standard for communication
between heterogeneous network computers
NSF - Network File System
• Sun Microsystems
• Allows multiple different computing
platforms to share files
– Between NetWare and Windows NT
– Between UNIX workstations, minicomputers,
and mainframe
NetWare
• Applications
– File server
– Printing server
• Global directory service: NetWare Directory
Service (NDS)
– Distributed
– Replicated
Windows NT
• Applications
– Web server
– Database server
– Application server
• Primary domain controller (PDC)
– Domain directory service
Sever NOSs - Functions
• Directory service
– Directory interoperability
• X.500
• Light-weight directory access protocol (LDAP)
• Microsoft’s open directory services interface (ODSI)
• Application services
–
–
–
–
Preemptive multitasking
32-bit execution
Multithreaded application support
Program execution in protected memory space
Sever NOSs - Functions
• File service
–
–
–
–
System management
SQL
Mail & schedule
SNA gateway to IBM mainframe network
• Network clients services
–
–
–
–
–
DOS
Windows
Apple
OS/2
UNIX or NFS
Sever NOSs - Functions
• Network protocols supported
– Multiprotocol routing
• Remote access and gateway service
• Management and administration service
–
–
–
–
–
Installation, configuration and administration
Integration and migration
Security: authentication, access rights
Audit trail and event logs
RAID
Sever NOSs Analysis
•
•
•
•
Hardware/platform
Installation and configuration
Networking and connectivity
Management and administration
Hardware/platform
•
•
•
•
•
•
•
Min/max memory
Min/max disk space
CPUs
Symmetrical multiprocessing
Preemptive multitasking
Multithreaded application support
Program execution in protected memory
space
Installation and Configuration
• Auto configuration
• No. of NIC drivers
Networking and Connectivity
•
•
•
•
•
•
•
Clients supported
Protocols supported
Naming services
Remote access
E-mail gateway
Web browser
Messaging services
Management and Administration
•
•
•
•
•
Central management
SNMP for enterprise management
Audit trails and event logs
Security
RAID
Server NOS Trends
• Symmetrical multiprocessing
• Clustering and fault tolerance
Assignment
• Review chapters 5-7
• Read Palmer: chapters 1-9
• Prepare exam 2