What is a VPN
VPN stands for Virtual Private Network. VPN is a private network which is constructed within a public network infrastructure (such as global internet). In this private network, access is controlled to permit peer connections only within a defined field of interest and is constructed.
A VPN network creates a secure connection over a public network i.e. the internet being one of the most important requirements of daily lives. The encryption for such a connection is provided by using algorithms for having security and the establishment of a reliable connection which is not possible in the case of a proxy server.
There are several different types of Virtual Private Networks. These VPN’s are available depending on the functional requirements and several different methods of constructing them. While selecting a VPN the problem which is to be solved should be considered and risk analysis should be done for that particular implementation. Some issues arise in growing the size of VPN and complexity in both implementing the VPN as well as in maintenance and trouble shooting, all must be considered before going for a particular VPN.
The different types of VPN are:
Network Layer VPN Link Layer VPN Application Layer VPN Transport Layer VPN
The purpose of VPN is to maintain the security of data transmission in and out of the intranet while keeping certain factors in consideration such as maintaining cost effectiveness. This connection is facilitated by a process called tunneling.
For establishing a VPN, the technologies such as Internet Protocol Security (IPsec), Secure Sockets Layer (SSL) and Transport Layer Security (TLS) can be utilized to encrypt the data packets and establish the secure tunnel through which they pass. SSL VPN is useful when IPsec has problems with IP Address translation.
A VPN client allows tunneling all the traffic over an encrypted, authenticated link which terminates at the VPN server. The VPN server decrypts the traffic and forwards it to whatever its original destination was by changing the source address of the traffic from the ISP assigned address. By this way all of the traffic appears to be coming from a single place and may not be limited by internal Internet firewall rules.
Thus VPN provides an encrypted and secure connection tunnel path from a user’s machine to its destination through the public Internet.