10-09-2014, 09:55 AM
WebOS
WebOS.ppt (Size: 1.26 MB / Downloads: 84)
Introduction
Operating System: provide common services to applications: IO, communication, storage.
With multiprogramming: include abstracting shared resource.
Local Area Network: birth of Network OS to provide access to network resources.
We need similar services for Wide Area Network distributed applications.
World Wide Web is the most widely used applications on the Internet.
Web made geographically distributed read-only data easy to use, but geographically distributed computing resources are not.
The result is that wide area applications that require access to remote CPU cycles, memory, or disk must be programmed in an ad hoc and application-specific manner.
=>Increase complexity!
WebOS Overview
Process Control:
In WebOS, executing a process on a remote node should be as simple as the corresponding local operation.
The underlying system is responsible for authenticating the identity of the requester and determining if the proper access rights are held.
Global Namespace
Many applications share state and transfer control using network communication
Parallel applications use shared memory or message passing
Using frameworks: global cache coherent file systems for communication and synchronization
Requirements: authentication, security and fault tolerance
Conclusion
Extending server functionality onto client machines allows for more flexible implementation of name resolution, load balancing, and fault tolerance.
Simplifying the implementation of a number of wide area applications.
Demonstrating how Rent-AServer, an application developed in framework