Many businesses and organizations nowadays use a VPN to communicate or transport voice, video, or data over a public network in a secure manner.
So, what is VPN?
A Virtual Private Network (VPN) is a technology that allows a private network to be extended over a less secure network. It gives remote users secure access to their company’s network, allowing them to securely send and receive data. As a result, it delivers security, expanded functionality, and private network administration policies.
Let’s take a look at how it works now.
It’s a fantastic way for remote workers and companies with foreign offices and partners to securely share information.
Common Types of VPN:
VPNs are divided into two categories:
VPDN (Virtual Private Dial-up Network)
A VPDN is a user-to-LAN link that connects remote users to the enterprise LAN. The employer must supply the software to the users in order for them to be able to access the Network Access Server (a service provider configuration) from their desktop, laptop, computer, mobile phone, or tablet. A third-party service provider provides this form of safe and encrypted connection between remote users and the company’s network.
In this diagram, NAS offers customers with access via the PSTN/ISDN, which are public network dial-up services. The L2TP network server, or LNS, is a device that acts as an L2TP server in the PPP system, allowing tunnel transmission using the VPDN tunneling protocol.
The LAC that sits between the LNS and a remote system (remote users and remote branches) communicates by:
encapsulating packets from a remote system and transmitting them to the LNS using L2TP
packets from the LNS are decapsulated and sent to a remote system
A PPP link or a local connection can be established between the LAC and the distant system, however in VPDN applications, a PPP link is always used.
A site-to-site VPN is another sort of VPN. For this, the corporation purchases dedicated gear that allows various locations to connect to the LAN over a public network, usually the internet. They are either intranet-based (available only by approved employees, organization members, or others) or extranet-based (open to permitted outsiders in part).
It is made up of two or more Site-to-Site VPN Gateways that can communicate bi-directionally with each other. These interconnected networks work together to form a single network. This type of VPN can be used to connect all of your company’s locations into a single network.
Features of VPN:
1. Secure channel
A VPN is a secure tunnel between a remote user and the organization’s network that allows data to be transmitted. The sent information cannot be seen by anybody else, ensuring confidentiality.
VPN security consists of a number of components that protect both the company’s private network and the outside network, which is usually the internet, through which the remote user connects. A firewall site between the client (remote users) and the host server, as well as a connection point with the private network, is the first step toward security. The remote user must connect to the firewall using an authenticated connection.
AAA authentication allows the provider to keep track of users in the “user@domain” format. If two VPNs share the same username, the WebVPN gateway domain is automatically added to the username, resulting in a user@domain. It’s similar to IPsec’s Group Lock functionality. As a result, the VPN is more secure and manageable because the @domain is always present until and unless another user produces or uses the same password.
It’s also a crucial component of a secure VPN. Encryption works by encrypting all records transferred from one laptop or computer in such a way that only the computer to which the data is being sent may decrypt it. Encryption types include:
Public-key encryption is a mechanism that uses a public key that is known by everyone and a private key that is only known by the message receiver.
The sender and receiver share a shared key that is used to decrypt and encrypt the message in symmetric-key encryption.
When using a VPN, tunneling is required to establish a network connection. Tunneling can be divided into two types:
In voluntary tunneling, the client establishes a connection with the service provider before creating a tunnel to the VPN server.
Compulsory tunneling: The service provider oversees the VPN connection between a VPN server and the client in this sort of tunneling.
VPN Tunnel Network Protocols
There are three basic network protocols that can be used with VPN tunnels, all of which are incompatible. These are some of them:
IPSec is a set of protocols that enable secure packet exchange at the IP layer using two encryption modes: transport and tunnel.
PPTP stands for Point-to-Point Tunneling Protocol, a novel technique that ensures secure message transfer between VPN nodes. Users can connect to their workplace network via the Internet using PPTP.
L2TP stands for Layer Two (2) Tunneling Protocol, and it allows ISPs to run VPNs. Cisco Systems L2F and Microsoft PPTP are two more tunneling techniques that are combined in L2TP.
You’ll need various components to establish your VPN, depending on whether you’re using a remote access or site-to-site VPN. A program for each remote workstation, dedicated hardware, such as the Cisco VPN Concentrator or a firewall, a VPN server, and a Network Access Server are all standard components (NAS).
Finally, while VPN has numerous advantages, including:
Control from afar
Unblock websites and get around filters
The ability to change your IP address
However, there are some downsides to it as well. Let’s look at some of the benefits and drawbacks of using this form of communication technology: