You need more information about IPSEC.
You want ot know what IPSEC is.
IPSec stands for Internet Protocol Security.
IPSec is a secutrity protocol for the communication at IP-Networks. IPSec works directly on top of the network layer (OSI model layer 3) of the OSI model. IPSec can protect the communication between a pair of gateways (routers, firewalls, etc.), a pair of hosts (computer clients, severs, etc.) of between a gateway and a host.
About the Author
Wim Peeters is electronics engineer with an additional master in IT and over 30 years of experience including time spent in support, development, consulting, training and database administration. Wim has worked with SQL Server since version 6.5. He has developed in C/C++, Java and C# on Windows and Linux in different European countries and different European languages. He writes knowledge base articles to solve IT problems and publishes them on the Lubby Knowledge Platform where he is one of the most important contributors and the main developer.