A virtual private network (VPN) is a network that uses a public telecommunication infrastructure, like the Internet, to provide remote access between two or more offices/individual users with secure access to their organizational network. In simple there are millions and millions of internet users all over the world, so while an person is traferring the data, it may be leaked out to others by some unsecure means. So inorder to share the information between two individuals alone, private network would be built, which gives access only to the 2 or a group defined users out of those millions and millions of unknown users. VPN - Virtual Private Network is nothing but building a tunnel, in a big mountain. A virtual private network can be contrasted with an expensive system of owned or leased lines that can only be used by a particular organization. The goal of a VPN is to provide access and security to the organizations at a lower cost, also with an additional level of security which involves encrypting not only the data, but also the originating and receiving network/IP addresses.
An SSL VPN (Secure Sockets Layer virtual private network) is a form of VPN that can be used with a standard Web browser as in we use the SSL certificates. These SSL VPN's help in securing organisational or individuals database or information, which they want to share between themselves. The SSL VPN can be a good choice for Government databases, schools, companies which manage huge databases, libraries and other public information which needs to be transmitted online via internet, but where trust would be an issue, though easy access and low cost is also important. Such kind of applications include Web-based e-mail, online forms, business directories, government directories, educational institutions database, file sharing, remote backup, remote desktop support, Remote system management, consumer-level e-commerce, Solid banking databases etc.
(An extract for better understanding) SSL is a protocol for managing the security of message transmission on the Internet. SSL is included as part of both the Microsoft and Netscape browsers and most Web server products. It employs the public-and-private key encryption system from RSA. As TLS (Transport Layer Security), a refinement of SSL, replaces the earlier protocol, an SSL VPN is sometimes referred to as a TLS VPN.
What is the difference between SSL VPN & VPN?
This has been a question for a long time. Many people keep asking what is the difference between SSL VPN and VPN, is that SSL VPN more secure than an IP Security VPN? and so on. In Simple terms, SSL VPN (secure sockets Layer VPN) uses private keys to encrypt data over an SSL connection. Which are used in conjunction with Internet browsers for clientless remotes, Where You can see HTTPS instead of the HTTP in the browser if that website/login is a secured one.And whereas VPN IPSEC is an Internet Protocol Security the Tunnel and Transport mode, where Transport mode only encrypts the data portion of the packet and Tunnel mode encrypts the whole packet. So that its not in the cluthes of all the internet users, though secure.
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