SUBMITTED BY:

ANKITA

3608106

CSE-1ST(3rd Year)

CONTENTSCONTENTS

Logo of VNC Abstract History Virtual Network Computing Types of VNC How VNC Woks? VNC Servers VNC Viewers Input

CONTINUEDCONTINUED………………

Connection Setup And Shutdown Installation Features Limitations Applications Future Work Conclusion References

LOGO OF VNCLOGO OF VNC

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.

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

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

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………

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.

HOW VNC WORKS?

VNC VIEWER

VNC SERVER

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.

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.

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

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.

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.

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]> 

VNC VIEWERSVNC VIEWERS

Open [Start] -> [Programs] -> [VNC] and click [VNC viewer]

Type server address and display number and click [OK].

Example Address Display No VNC server field 192.168.0.1 0 192.168.0.1:0 Hoge-server 1 hoge-

server:1

TYPE SERVER PASSWORD AND CLICK [OK].

NOW THE VIEWER CAN VIEW THE DISPLAY.

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

FEATURESFEATURES

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

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.

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.

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.

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.

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/xvnc.html. Retrieved 2007-03-24.