Internet between different gateway

---

I am trying to understand the concept for routing/Nat/Gateway.. Lets say i have a different net that have his firewall,router,switches and them i have another separated network with different net ,firewall, router,switch... If one of the net has internet service how could i pass this service to the other network if both have firewall...???? Any help to understand the process or the logic to do this.

@Yihad-Fadlallah-0,

Each network would have a (LAN) would need a router between itself and the rest of the world. This can come in the form of a router or a firewall, depending on the need. On the LAN, they would use Private IP Addresses that would use NAT to reach Public IP addresses on the internet. The LAN would connect to one port of router; the ISP connection to another port. The router or firewall would allow this translation to reach across the internet.

If both networks need to be connected directly to each other, they would probably create a Virtual Private Network (VPN) establishing a "tunnel" through the ISPs and across the internet to each other. Logically, the Internet Service Providers (ISPs) between your two networks would be "transparent".

So i will need to make a NAT from the second network in the first firewall that resides with the ISP connection,right???

@Yihad-Fadlallah-0,

If both networks are connected to an ISP, you will need to nat your internal IP addresses to your public IP(s) on both ends.

@Ronnie-Wong said in Internet between different gateway:

@Yihad-Fadlallah-0,

If both networks are connected to an ISP, you will need to nat your internal IP addresses to your public IP(s) on both ends.

Hi, the networks are different only one is connected to an isp and the other is not. The one that is connected is in another building and the other firewall doesn't have any isp connected. I want to make that network reach the isp that has the building.

@Yihad-Fadlallah-0,

if they both LANs need access to the internet. They will both need to have NAT.

@Ronnie-Wong
So the nat rule that will be configure on the second firewall should be the public ip address from the isp or the private ip address from the 1st firewall that has the isp connection direclty connected?

@Yihad-Fadlallah-0,

I'm not exactly visualizing how this works. So apologies for my ignorance here. Here' is what I am visualizing:

• On the Firewall connected to the ISP. I would setup NAT outside
  • For link connecting to the ISP
• Then setup NAT inside
  • For link connecting to the LAN directly attached here
  • for the link connecting to the 2nd Firewall.

You shouldn't need to configure NAT on the second firewall.

If this isn't what you're trying to do, you'll have to clarify for me.