Virtual network computing

presenation on virtual netwok computing

1. SUBMITTED BY:
ANKITA
3608106
CSE-1
ST
(3
rd
Year)

2. CONTENTSCONTENTS
Logo of VNC
Abstract
History
Virtual Network Computing
Types of VNC
How VNC Woks?
VNC Servers
VNC Viewers
Input

3. CONTINUEDCONTINUED………………
Connection Setup And Shutdown
Installation
Features
Limitations
Applications
Future Work
Conclusion
References

4. LOGO OF VNCLOGO OF VNC

5. ABSTRACT..ABSTRACT..
Have you ever found yourself away from home, wishing
you had your desktop machine with you? Have you
ever wished you could show someone, remotely, how
to do something instead of talking them through it over
the phone? These things and much more can be done
with a nifty little freeware utility called Virtual Network
Computing, or VNC
In contrast to many recent Internet applications, which
have focused on giving users access to resources
located anywhere in the world from their home
computing environments, VNC provides access to
home computing environments from anywhere in the
world.

6. HISTORYHISTORY
Created by the Olivetti & Oracle Research Lab (ORL),
which was then owned by Olivetti and Oracle
Corporation on Apr 20, 2004.
In 1999 AT&T acquired the lab, and in 2002 closed
down the lab's research efforts.
Developers who worked on VNC while still at the
AT&T Research Lab are:
Tristan Richardson(inventor)
AndyHarter(project leader)
Quentin Stafford-Fraser
James Wetherill

7. Virtual network computing (V.N.C) is a process of
controlling a computer by sitting kilometers away through
internet.
VNC, which stands for Virtual Network Computing, is a
client/server-based, stateless, platform-independent
protocol developed at ORL.
It is a graphical desktop sharing system that uses the RFB
protocol to remotely control another computer.
It transmits the keyboard and mouse events from one
computer to another, relaying the graphical screen updates
back in the other direction, over a network.
As the OS is a graphical user interface controlling is done by
mouse events.
The screen resolution of the server and the viewer must be
the same.
VIRTUAL NETWORK COMPUTING

8. A VNC system consists of a client, a server, and a
communication protocol.
The VNC server is the program on the machine that shares
its screen. The server passively allows the client to take control
of it.
The VNC client (or viewer) is the program that watches,
controls, and interacts with the server. The client controls the
server.
The VNC protocol (RFB) is very simple, based on one
graphic primitive from server to client ("Put a rectangle of pixel
data at the specified X,Y position") and event messages from
client to server.
CONTINUED………

9. TYPES OF VNCTYPES OF VNC
Real VNC - Runs on Windows, Mac OS x, Java
Platform and many UNIX like OS.
Tight VNC -Cross platform open source remote
desktop software. Provides µtight encoding¶ which
improves performance over low bandwidth
connections. Runs on Windows and Linux.
Ultra VNC -Open source and free application for
Windows. Similar to Real VNC free edition along
with
various features.

10. HOW VNC WORKS?
VNC VIEWER
VNC SERVER

11. 2).The interface for most VNCs can operate from any operating system,
such as Windows, Macintosh, or Unix. Because information is
transmitted over the Internet, the system eliminates many of the
traditional cross-platform problems. Just as a website can be viewed on
many different operating systems, so can VNC control operate from
many different computer types.
3). While "VNC" is a generic term for this type of software, many brands
of the software exist, with packages available for all major operating
systems.
4). The connection used to interface data is protected by a password.
This prevents unauthorized users from controlling a remote computer.
Once the connection is established, information begins to be exchanged.
Details on mouse location, keyboard entry, and screen updates are fed
over the secure connection, keeping the computers synchronized.
1).Most VNC systems are controlled from a simple
graphic user interface. Once the software has been
installed on a remote computer, it can be accessed
from any location. A server constantly monitors
inputs and outputs from one computer, and updates
them to the second location.

12. VNC SERVERSVNC SERVERS
It communicates interaction from the remote
machine to the local machine.
It exports the view of a remote environment to a local
machine
Multiple clients may connect to a VNC server at the
same time ‘desktop´ screen
Inputs keyboard and mouse inputs from local
machine to remote machine.

13. VNC VIEWERSVNC VIEWERS
It provides the local half of the remote controlled
system.
Communicates interactions between the local machine
to the remote machine.
Imports the view of the remote desktop screen
environment to the local machine.
Exports keyboards and mouse inputs from local
machine
to remote machine.
VNC works at Frame Buffer level i.e. it uses the RFB
(Remote Frame Buffer) Protocol.
It is a simple protocol for remote access to graphical
user interfaces.
It is a Thin-Client System

14. INPUTINPUT
The client sends input events to the server
whenever the user presses a key or
pointer button, or moves the pointing device.
Input events can also be synthesized from
other nonstandard I/O devices.

15. CONNECTION SETUP & SHUTDOWNCONNECTION SETUP & SHUTDOWN
The server first requests authentication from the client,
using a challenge response VNC server VNC viewer
(client) VNC protocol scheme.
The client typically requires the user to
enter a password at this point.
Exchange of messages for details takes
place.
Because of the stateless nature of the client, either side
can close the connection at any time without an
adverse consequences.

16. INSTALLATIONINSTALLATION
Download vnc-3.3.3r7_x86_win32.zip from the
Internet
Extract the file.
Open WinVNC directory and run Setup.exe
Open [Start] -> [Programs] -> [VNC] ->
[Administrative Tools] and click [Install WinVNC
Service]
Open [Services] window, select VNC server and start
the service.
After opening [Property Page], type password and click
[OK]> 

18. VNC VIEWERSVNC VIEWERS
Open [Start] -> [Programs] -> [VNC] and click [VNC
viewer]
Type server address and display number and click
[OK].
Example Address Display NoVNC server field
192.168.0.1 0 192.168.0.1:0
Hoge-server 1 hoge-
server:1

19. TYPE SERVER PASSWORD AND CLICK [OK].
NOW THE VIEWER CAN VIEW THE DISPLAY.

21. VIEW FROM BROWSERVIEW FROM BROWSER
Open your browser and type address.
Example Address Address
192.168.0.1 http://192.168.0.1:5800
hoge-server http://hoge-server:5801

23. FEATURESFEATURES
It is small and simple. No installation is
required.
It is truly platform-independent.
It is sharable.
It is free.
It is stateless.

24. LIMITATIONSLIMITATIONS
Doesn't have modem access features.
Display can be a bit slow, jerky and/or
incomplete.
It requires good bandwidth for it to function
properly.
File systems are still separate between
different OS.

25. APPLICATIONSAPPLICATIONS
Access important information.
Check-up emails and download.
Use a modem to dial a telephone answering machine
and reprogram it through a graphical interface.
Start/stop any processing or computation.

26. FUTURE WORKFUTURE WORK
Hardware such as this, if made in quantity,
could be very cheap and could allow for
mobility of much more than just a
conventional ‘desktop.´
If built into television sets, VNC viewers
could allow them to act as displays for a
very wide range of devices²including, of
course, the PC at the office.

27. CONCLUSIONCONCLUSION
VNC is a very impressive product, especially
considering that it's free.
its main advantage over its commercial competitors is
that it is open source, so anyone with programming
skills can contribute towards it and so make it an even
better, more flexible product.
Even in its current form, its remote control applications
are almost limitless, and it wills no doubt find many uses
and supporters in a typical support environment
VNC means Really here. Virtually there.

28. REFERENCESREFERENCES
en.wikipedia.org/wiki/Virtual_Network_Computing

www.cl.cam.ac.uk/research/dtg/attarchive/pub/docs/att/tr.98.1.pdf
 ^ The VNC family of Remote Control Applications: a
list of VNC variants
 ^ "RealVNC - Frequently asked questions".
http://www.realvnc.com/support/faq.html.
 ^ "UltraVnc Configuration".
http://uvnc.com/install/configuration.html.
 ^” AT&T Laboratories Cambridge (1999). "X-based
VNC server". Virtual Network Computing.
http://www.cl.cam.ac.uk/research/dtg/attarchive/vnc/xvn
c.html. Retrieved 2007-03-24.