VPN – Virtual Private Network is a revolutionary technology designed in order to help in remote connection to the private network so that one can get 'virtually' connected to that network as though they are on-site and plugged into the LAN.
This technology is very popular among remote workers who are trying to connect to office resources without having to be physically present in the office. There are several types and uses of VPNs. You can also visit this site to get the best VPN remote access services.
There are a variety of VPN routers available. The most popular is LAN-to-LAN, which connects multiple networks together. Typically, corporate offices want to connect to their many branches for internal communication and access to various resources.
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This allows the border firewall to block any external resources trying to connect to the protected resource, but remote access VPN connections are still allowed because they are "internal" i.e. already exists as a trustworthy side of the firewall.
IPSec, a security protocol suite primarily used for LAN-to-LAN VPNs, provides the most stable and reliable suite of encryption and authentication products.
The remote worker is actually connecting to the remote VPN and it's just a temporary or "dial-up" connection. Microsoft currently has PPTP (Point-to-Point Tunneling Protocol) built-in which is an easy method to implement.
There's no denying that PPTP is based on a weak encryption protocol called MS-CHAP, which in turn makes it a less affordable option, but remote access VPS is constantly evolving!