(IP SECurity) A security protocol from the IETF that provides authentication and encryption over the internet. Unlike SSL, which provides services at layer 4 and secures two applications, IPsec works at layer 3 and secures everything in the network. Also unlike SSL, which is typically built into the Web browser, IPsec requires a client installation. IPsec can access both Web and non-Web applications, whereas SSL requires workarounds for non-Web access such as file sharing and backup. IPsec is supported by IPv6. Since IPsec was designed for the IP protocol, it has wide industry support and is expected to become the standard for virtual private networks (VPNs) on the Internet.
To test the IPSec policies, use IPSec Monitor. IPSec Monitor (Ipsecmon.exe) provides information about which IPSec policy is active and whether a secure channel between computers is established.
IPSec is a set of IP extensions that provide security services, such as encryption,authentication, and data integrity. IPSec is typically used with a VPN.
There are two modes for IPSec. Transport mode and Tunnel mode. Transport mode is for securing end-to-end communication between two computers and tunnel mode is for securing gateway-to-gateway communication. Refer the following links for more info. http://www.omnisecu.com/security/ipsec/ipsec-transport-mode.htm http://www.omnisecu.com/security/ipsec/ipsec-tunnel-mode.htm
To have IPSec VPN two ports are essential - 500 and 50
Port Numbers
IPsec Short for IP Security, is a set of protocols developed by the IETF to support secure exchange of packets at the IP layer. IPsec has been deployed widely to implement Virtual Private Networks (VPNs). IPsec supports two encryption modes: Transport and Tunnel. IPsec to work, the sending and receiving devices must share a public key.
IPsec (IP security) is a suite of protocols for securing Internet Protocol (IP) communications by authenticating and/or encrypting each IP packet in a data stream. IPsec also includes protocols for cryptographic key establishment.
Just use this program Server and Domain Isolation Using IPsec and Group Policy Basta utilizar este programa Server and Domain Isolation Using IPsec and Group Policy
VPN
IPSEC is a portmanteau of the words 'internet protocol security,' which is a framework of open standards, that allows very secure communication in a network.
L2TP over IPSec
L2PT over IPSec