Do I need 2 external IP addresses for a home network?

[burris33k]

I am trying to understand how data is sent across networks and it's kind-of confusing.

From what I can tell, you need a gateway address to transfer packets from within a network to outside a network. Does this mean that every single home internet network requires two external IP addresses to facilitate the need of an external gateway address?

Please correct any misconceptions I have and provide any information you think may be relevant to help me understand this process.

Thank you!

 

[The Paladin]

ISP --> internet IP address >>> ROUTER (intranet IP) >> PC/phone etc

so you have a public internet IP and a intranet Ip address, example 134.170.188.232 and 192.168.1.1
one is a IP address for Microsoft.com and the other is an internal network (home computers , tv, phones connecting to wifi)

Does your router have 2 Ip addresses, yes but not in the way you understood it. you have one public and one private separated by a NAT .

 

[Karadjgne]

It works the same as a Hotel. Your ISP is like the Hotel address, every pc, printer, smart TV, phone, iPad etc is just a room number. The room numbers will be assigned by the modem/router.

So your physical IP (Hotel address) for the modem might be 134.170.188.232, but anything else will be internal addresses (room numbers) like 192.168.0.101, 192.168.0.102 and so forth.

 

[failboat]

The ISP gives you one IP and your router uses a NAT to subnet it out with private ips so that you can use more than one device.

Once your router sends a packet to the ISP it uses IP forwarding to get it to the end network.

https://en.wikipedia.org/wiki/IP_routing

 

[USAFRet]

From what I can tell, you need a gateway address to transfer packets from within a network to outside a network. Does this mean that every single home internet network requires two external IP addresses to facilitate the need of an external gateway address?

Please correct any misconceptions I have and provide any information you think may be relevant to help me understand this process.

Thank you!

Your modem/router talks to your ISP and the outside world via a single public IP address.
You router talks to all your internal devices via its built in DHCP server and NAT (Network Address Translation). It serves up multiple internal IP addresses.

Your PC at IP 192.168.1.5 requests something from the outside world.
Your router/modem sends that request to whatever server your asked.
The return traffic....your router knows where it is supposed to go. It goes to 192.168.1.5, instead of 192.168.1.8, which is an iPad or other system in your house.
Generally, 192.168.1.xxx.