Now let's start talking about IPsec VPN. IPsec VPN is the only solution available at this point when it comes to securing VPN tunnels between site offices at a distance. We can protect these VPN tunnels using IPsec. IPsec is a protocol. And this will protect data voice and video transmissions between the sites. Now, how does IPsec protects the VPN tunnels?

That's always the question, of course by encrypting the packets. Remember IPsec is a layer three protocol that authenticates and encrypts data packets over IP network. The four features are number one, it's transparent to applications Because it operates at layer three. It provides peer authentication. It provides data integrity, and it maintains it through advanced algorithms. It provides data confidentiality during the transmission.

So in this slide, I'm just showing you a central office connected to branch offices. And in the dotted red lines between these branch offices, you can see there is a VPN connection between the sides. And that's basically a typical corporate environment with multiple sites across different geographical locations. Yeah, so let's move on to our next topic.