In computing, Virtual Network Computing (VNC) is a graphical desktop sharing system that uses the Remote FrameBuffer protocol (RFB) 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. Without further ado, here are 8 free and some are open source VNC client/server.
VNC, the Remote FrameBuffer protocol (RFB) allows a desktop to be viewed and controlled remotely over the Internet. A VNC server must be run on the computer sharing the desktop, a VNC client must be run on the computer that will access the shared desktop.
TightVNC is a free remote control software package. With TightVNC, you can see the desktop of a remote machine and control it with your local mouse and keyboard, just like you would do it sitting in the front of that computer.
Remmina is a remote desktop client written in GTK+, aiming to be useful for system administrators and travellers, who need to work with lots of remote computers in front of either large monitors or tiny netbooks. Remmina supports multiple network protocols in an integrated and consistent user interface.
TigerVNC is a high-performance, platform-neutral implementation of VNC (Virtual Network Computing), a client/server application that allows users to launch and interact with graphical applications on remote machines. TigerVNC provides the levels of performance necessary to run 3D and video applications, and it attempts to maintain a common look and feel and re-use components, where possible, across the various platforms that it supports. TigerVNC also provides extensions for advanced authentication methods and TLS encryption.
X2Go is an open source remote desktop software for Linux that uses the NX technology protocol. X2Go can be used to access PC desktops, but its main use case is providing secure standalone remote sessions via ssh. The server package must be installed on a Linux host; client packages can be run on Linux, OS X, or Windows. Basic features of X2Go
Because the Guacamole client is an HTML5 web application, use of your computers is not tied to any one device or location. As long as you have access to a web browser, you have access to your machines.
Apache Guacamole is and will always be free and open source software. It is licensed under the Apache License, Version 2.0, and is actively maintained by a community of developers that use Guacamole to access their own development environments.
The original GPLed source code has fed into several other versions of VNC. Such forking has not led to compatibility problems because the RFB protocol is designed to be extensible. VNC clients and servers negotiate their capabilities with handshaking in order to use the most appropriate options supported at both ends.
The name Virtual Network Computer/Computing (VNC) originated with ORL's work on a thin client called the Videotile, which also used the RFB protocol. The Videotile had an LCD display with pen input and a fast ATM connection to the network. At the time, network computer was commonly used as a synonym for a thin client; VNC is essentially a software-only (i.e. virtual) network computer.
The server sends small rectangles of the framebuffer to the client. In its simplest form, the VNC protocol can use a lot of bandwidth, so various methods have been devised to reduce the communication overhead. For example, there are various encodings (methods to determine the most efficient way to transfer these rectangles). The VNC protocol allows the client and server to negotiate which encoding they will use. The simplest encoding, supported by all clients and servers, is raw encoding, which sends pixel data in left-to-right scanline order, and after the original full screen has been transmitted, transfers only rectangles that change. This encoding works very well if only a small portion of the screen changes from one frame to the next (as when a mouse pointer moves across a desktop, or when text is written at the cursor), but bandwidth demands get very high if a lot of pixels change at the same time (such as when scrolling a window or viewing full-screen video).
VNC by default uses TCP port 5900+N, where N is the display number (usually :0 for a physical display). Several implementations also start a basic HTTP server on port 5800+N to provide a VNC viewer as a Java applet, allowing easy connection through any Java-enabled web-browser. Different port assignments can be used as long as both client and server are configured accordingly. A HTML5 VNC client implementation for modern browsers (no plugins required) exists too.
Xvnc is the Unix VNC server, which is based on a standard X server. To applications, Xvnc appears as an X \"server\" (i.e., it displays client windows), and to remote VNC users it is a VNC server. Applications can display themselves on Xvnc as if it were a normal X display, but they will appear on any connected VNC viewers rather than on a physical screen. Alternatively, a machine (which may be a workstation or a network server) with screen, keyboard, and mouse can be set up to boot and run the VNC server as a service or daemon, then the screen, keyboard, and mouse can be removed and the machine stored in an out-of-the way location.
Remote Framebuffer, or RFB, is the protocol that governs the format of the data that passes between the client and server within the VNC system. This is what allows a client to view and control another computer remotely. It is applicable to all windowing applications and systems, which means that it works across platforms such as Windows, macOS, Linux, and other popular operating systems.
The place where the user sits, with the display, mouse, and keyboard capabilities, is called the RFB client or viewer. The place where the framebuffer changes originate (as in the windowing system) is called the RFB server. Remote Framebuffer is designed so that clients can run on the widest range of hardware and so that implementing a client is as simple as possible, with very few requirements needed from the client.
RFB started as a very simple protocol but has been enhanced to include features such as file transfer, more refined compression, and stronger security measures as it has developed. Seamless cross-compatibility between VNC clients and servers is made possible because they are able to negotiate a connection which uses the best RFB version, as well as security and compression options that are supported by both.
VNC stands for Virtual Network Computing - it is software that enables you to have a virtual desktop (server) on another computer. This virtual desktop can then be accessed using various clients (X11 interfaces, browsers, etc), giving you access to your virtual desktop from any location. For security reasons, the IRTF allows connections ONLY from RealVNC clients. Visit the VNC home page for more information.
The stand-alone vnc client software from RealVNC must be installed on the computer. The vnc client (vncviewer) should be downloaded from the vnc webpage and may be installed on Linux, Unix, Mac, and Windows computers. A ssh client is also required to tunnel your vncviewer connection if your site requires this. A three-button mouse is required as well as a monitor capable of displaying 1080p resolution.
The RealVNC clients can be downloaded by going to www.realvnc.com. Click \"Download\" for the version for your operating system and fill out the form. You may download as many versions as you will need and all the \"Viewer Only\" software is free. Only the Enterprise packages that include a server are not free.
Note that any combination and number of viewers may be used to view the desktop from a vnc server. For example, one observer could be running on a Mac using vncviewer, another a client running on a Windows pc, and a third observer using a client on a Linux computer.
All clients require a hostname and display number to which the client will connect. The hostname should be stefan.ifa.hawaii.edu or 188.8.131.52 and the display number is designated as n below and should have been provided to you by the telescope operator or IRTF staff member from whom you obtained the VNC password.
When you are finished using the vnc server that was made for you (not the instrument servers), request that the telescope operator (or IRTF staff member) kill the server. You will need to provide the display number and the program number for which the server was created. Please note that killing the server will disconnect all the client sessions and shut down the server. If you do not explicitly request the telescope operator to do this, it will be done at the end of every night/day anyway, so please make sure you have saved any work you are doing before closing down after your observing slot.
Once the ssh tunnel has been set up, you run the vnc client on the local machine from a second terminal or from the menus, and connect to the server localhost:59XX. It is very important that you not start the vnc client in the same terminal that is logged into stefan, as it will be extremely slow due to the fact that the vnc client is being exported from stefan to your local host.
You can use the Remote Desktop client for Mac to work with Windows apps, resources, and desktops from your Mac computer. Use the following information to get started - and check out the FAQ if you have questions. 1e1e36bf2d