Have you ever used any application for remote access, especially for remote desktop? Do you want to know how does the whole system work and which protocols are used for successful connection? Thanks to the wide range of remote desktop applications it´s not easy to choose the right one. But as you know, used technologies aren't so different from each other. In this article we will explain some basic remote desktop terminology.
Remote desktop across classic platforms
We start the description with classic solution based on Microsoft and Apple platforms without cloud computing in the middle.
We bet that everybody knows “Remote desktop connection” that OS Windows use or “Remote Desktop” used by MAC OS. This feature allows to connect computers directly together and work with the remote desktop as with your own. If you want to know which technology is used for graphic rendering, read this short description on Microsoft technet page: “On the server, RDP uses its own video driver to render display output by constructing the rendering information into network packets by using RDP protocol and sending them over the network to the client. On the client, RDP receives rendering data and interprets the packets into corresponding Microsoft Windows graphics device interface (GDI) API calls. For the input path, client mouse and keyboard events are redirected from the client to the server. On the server, RDP uses its own on-screen keyboard and mouse driver to receive these keyboard and mouse events.”
Apple has its own solution called ARD - Apple Remote Desktop. The first version was based on UDP protocol using port 3283 which allowed to restart or turn off computers, lock the computer desktop and wake up computer from sleep remotely. This application was released in 2002. Current version 3.4 is compatible with VNC SW and supports 128b AES cryptography. Apple Remote Desktop application is based - without ARD 1.0 - on ARD protocol and UDP protocol is only a history now.
Above we have mentioned two major competitors to show you a basic functionality of Remote desktop connection between two computers which are connected directly with each other. Let´s have a look on Remote connection between computers with the 3rd party in the middle.
Remote desktop based on Cloud Computing
The major difference compared to the direct connection is that between client’s browser and company´s (provider´s service) host is server (or datacenter) which compresses the transmitted data and finally enables faster transfer from the client to the host and in the opposite way. All remote access products use a proprietary protocol that is transmitted via SSL/TLS where SSL certificates for each remote desktop connection are created.
In next article we will describe graphic solution of remote desktop services and we will compare them with / without cloud servers solution in the middle.