VPN is an abbreviation for Virtual Private Network. It allows a person to safely and discreetly connect to a private network over the Web. VPN establishes a secure channel known as a VPN tunnel, through which all Internet traffic and conversation is routed.
A Remote Access VPN allows people to connect to a private network and remotely access all of its resources and services. The person's connection to the private network is made over the Internet, and the connectivity is safe and confidential. Remote Access VPN is beneficial to both residential and business users.
While away from the office, a corporate employee utilizes a VPN to connect to his or her employer's private network and remotely access files and resources on the private network. Private VPN users or home VPN users typically utilize VPN services to circumvent regional Internet censorship and access restricted websites.
A Site-to-Site VPN, also known as a Router-to-Router VPN, is widely employed in big corporations. Site-to-site VPN is used by businesses and organizations with branches offices in different places to link the network of one office location to the network of another office location.
Intranet-based VPN − This form of VPN is used when many offices of the same organization are linked using Site-to-Site VPN technology.
Extranet-based VPN − Extranet-based VPN is used when a firm uses a Site-to-site VPN type to connect to the office of another organization.
Site-to-site VPN, in essence, creates an artificial link between networks at geographically separated workplaces and connects them over the Web to maintain a safe and private connection between the networks. Because Site-to-Site VPN relies on Router-to-Router communication, one router serves as a VPN Client and another as a VPN Server. Communication can commence only when the two routers' authenticity has been validated. Only once the authentication between the two routers is verified then communication begins.
IPsec, or Internet Protocol Security, is a protocol used to secure Online communication over an IP network. IPsec protects Internet Protocol communication by validating the session and encrypting each datagram transmitted throughout the connection.
IPsec operates in two modes −
The transit mode encrypts data within the datagram, whereas the tunnelling mode encrypts the whole datagram. IPsec may also be used in conjunction with other security practices to strengthen the safety system.
L2TP, or Layer 2 Tunnelling Protocol, is a tunnelling protocol that is frequently used in conjunction with another VPN security protocol, such as IPsec, to build a highly secure VPN connection. L2TP creates a tunnel between two L2TP connection points, and the IPsec protocol encrypting data and ensures secure connections over the tunnel.
The Point–to–Point Tunnelling Protocol (PPTP) creates a tunnel and restricts the data stream. To encrypt data between connections, the Point-to-Point Protocol (PPP) is utilized. PPTP is a popular VPN protocol that has been used since the early years of Windows.
Using SSL/TLS, a VPN connection is established between the user's web browser and the VPN server, with access restricted to just specific apps rather than being available to everyone on the network. SSL and TLS protocols are frequently used by online purchasing websites.
As web browsers are integrated with SSL and TLS, switching to SSL is simple and requires practically no action from the user. The URL for SSL connections begins with "https" rather than "http."
OpenVPN is a free and open-source VPN protocol that is frequently used to establish point-to-point and site-to-site connections. It employs a conventional security mechanism based on SSL and TLS.
Secure Shell (SSH) creates the VPN connection that allows data to be sent while also ensuring that the tunnel is secured. An SSH client creates SSH connections, and data is transmitted from a local port to the distant server over the encrypted channel.