A distributed operating system is an extension of the network operating system that supports higher levels of communication and integration of the machines on the network. This system looks to its users like an ordinary centralized operating system but runs on multiple, independent central processing units (CPUs).

1. NADAR SARASWATHI COLLEGE OF ARTS&SCIENCE,THENI
V.VANMATHY
I MSC(CS)
DEPARTMENT OF COMPUTER SCIENCE AND
INFORMATION TECHOLOGY

2. DISTRIBUTED
OPERATING SYSTEM
TOPIC

3.  A distributed operating system I system
software over a collection of independent,
networked, communicating, and physically
separate computational nodes.
 They handle job which are serviced by multiple
CPU. each individual node hold a specific
software subet of the global aggregate
operating system

5. Types of Operating Systems
 An Operating System performs all the basic
tasks like managing files, processes, and
memory. Thus operating system acts as the
manager of all the resources, i.e. resource
manager. Thus, the operating system becomes
an interface between user and machine.

10. Two types of Real-Time Operating system
 Hard Real-Time Systems:
 Soft Real-Time Systems:

11.  Distributed system I collection of loosely
coupled processors interconnected by a
communications network.
 Processors are also called nodes, computers
machines, hosts etc.
 Site I location where the processor resides.
 Generally a server has a resource a client node
that a different site wants to use.

14.  Resource sharing
 Reliability
 Computation speedup
 Communication

15. Resource sharing:
 Sharing and printing files at remote sites
processing information in a distributed
database using remote specialized hardware
devices

16.  Transfer, reintegrate Detect and recover from
site failure, function transfer, reintegrate failed
site.

17.  Load sharing or job migration
 Reliability- detect and recover from site failure,
function transfer, reintegrate failed site

18.  Transfer of resources and computation among
processors.

19.  Network operating systems
 Distributed operating system

20.  Users are aware of multiplicity of machines
 Access to resources of various machines is
done explicitly by:
 Remote logging into the appropriate remote
machine(telnet ,ssh)
 Remote desktop(micro soft window)
 Transferring data from remote machine to local
machines, via the file transfer
protocol(FTP)mechanism

22.  Users not aware of multiplicity of machines
access to remote resources similar to access to
local resources.
 Data migration
 Computation migration

23.  Process migration execute an entire process, or
parts of it, at different sites by migrating it
prior to or during the process
 Load balancing
 Computation speedup
 Hardware preference
 Software preference
 Data access