Operating system is developed to ease people daily life. For user benefits and needs the operating system may be single user or distributed. In distributed systems, many computers connected to each other and share their resources with each other. There are some advantages and disadvantages of distributed operating system that we will discuss.
Advantages of distributed operating systems:-
- Give more performance than single system
- If one pc in distributed system malfunction or corrupts then other node or pc will take care of
- More resources can be added easily
- Resources like printers can be shared on multiple pc’s
Disadvantages of distributed operating systems:-
- Security problem due to sharing
- Some messages can be lost in the network system
- Bandwidth is another problem if there is large data then all network wires to be replaced which tends to become expensive
- Overloading is another problem in distributed operating systems
- If there is a database connected on local system and many users accessing that database through remote or distributed way then performance become slow
- The databases in network operating is difficult to administrate then single user system
Examples of distributed operating systems:-
- Windows server 2003
- Windows server 2008
- Windows server 2012
- Ubuntu
- Linux (Apache Server)
Overview:
These types of systems appear to the user as they are single user systems. These systems share their memory, disk and user feel no difficulty in navigating through data. There seem to be one processor with many computers attach to it. User store something in his pc and the file is stored in multiple locations i.e. in attached computers so losing of data is recovered.
If any PC is loading higher i.e. if many requests are exchanging between single PC so load balancing occurs. In that case requests are shared to neighbor attached PC. If there become more load on the network then it can be expandable by attaching more systems to the network.
In the network file and folders are synchronized and naming conventions are used so that no error occurs during retrieving of data. Caching is also used in data manipulation. For naming files single namespace is used on all the computers. But the file system acts different for each computer.
If there become updates in the file then it is written on one computer and changes are transferred to all the computers so the file seem same. There occurs locking of files during read/write action so no deadlock occurs between different computers.
There also occurs sessions like you can read, write files in one session and session closes and then other user can do the same and so on.