Questions on public IP and the router

[cydz]

Hello!

I am hoping someone can answer a question I have about computer networking regarding the public IP and the router.

I ran an nmap -A of my home network and found that it identified my linux machine as the OS. Why is this? Why didn't it simply state what ports were open and what services are running? After all, there are 3 different machines on my network all running different OS.

Is there a way of pulling the router's IP from the public IP? Or are they both one in the same? How would I access my router from an outside network?

I hope someone can answer my questions!

 

[Emerald]

if you don't have a Static Public IP the easiest way to access your router from outside is to use DDNS

 

[cydz]

I'm using a static public IP.

 

[Emerald]

then by using you public IP you should be able to access you router if you enabled remote management on the router.

if you need to access a computer behind the router, you will need to setup port forwards in the router directing it to the computer to be accessed.

 

[cydz]

I see, so is this also why when I do an nmap scan it keeps saying the host is down? There are currently 3 machines active on the network. By scanning it from the outside it will keep saying it's down unless the router has been configured to allow outside access?

 

[john-b691]

That is correct. This feature is referred to as port forwarding in many routers. To really make a machine visible to something like nmap you would have to use the DMZ option many routers have.

I would not recommend you do either unless you have a very good reason. Nmap when it told you it was linux was scanning the router itself. Many routers software is a unix variant so it may get identified that way.

 

[Emerald]

if you want to access the LAN from the outside, setup a VPN