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Questions tagged [nat]

Network Address Translation, a technology used to translate a private IP address into a public IP.

Network Address Translation (NAT) is a method of connecting multiple computers to the Internet (or any other IP network) using one IP address.

NAT is also known as IP masquerading.

RFC 2663 - IP Network Address Translator (NAT) Terminology and Considerations

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How to do networking between virtual machines in VirtualBox?

I have two virtual machines in VirtualBox. I would like to do networking between them. For the moment I have the default configuration on both, but they seem to have the same IP-address 10.0.2.15. I would also like to be able to use Internet with…
Jonas
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SSH access to office host behind NAT router

I would like to access the ssh port of my office linux host from home. Unfortunately the host is located behind a NAT router. So, the IP address is not publicly available. There is however access to another internet host (Server) which is…
ritter
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How does a NAT server forward ping ICMP echo reply packets to users?

NAT uses an IP address port number combination to hash the outgoing requests. Since ping requests consist of ICMP echo request packets, they do not have any associated port number. How does a NAT server forward the replies to the hosts inside the…
Rohit Banga
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Safely adding insecure devices to my home network

I have a few Internet-connected devices which I don't trust to be secure, but that I would like to use anyway (a smart TV and some off-the-shelf home automation devices). I don't want them on the same network as my computers. My current solution is…
Chris B
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No internet connection in Virtual Machine on selecting NAT in VMWare workstation

I'm facing this strange problem from yesterday where if I select NAT as the network adapter in VMWare, I'm not getting any internet connection in the VM. I have a requirement where I have to have the network adapter as NAT. Internet is working…
Amogh Natu
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How will a router with NAT disabled behave?

I noticed that my home router has the option to disable NAT. How will the router behave with NAT turned off? Will it simply broadcast all incoming traffic to the subnet?
BSmith
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4 answers

Does mailx send mail using an SMTP relay or does it directly connect to the target SMTP server?

Suppose i send a mail using the following the following command: mailx person@x.com then does mailx first try to find out the SMTP server of my ISP for relaying the mail or does it connect directly. Does it depend on whether my PC has a public IP…
Rohit Banga
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Is it possible to host a web server from behind a NAT

My PC is behind a NAT router that has a public IP address. If I want to host a website then I believe I need a domain name which I can purchase from some site which would pledge to resolve all DNS requests for that domain name and send the IP…
Rohit Banga
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How is double NAT bad practically?

As the ISP-provided modem was generating pretty weak WiFi signal I've disabled its WiFi function, bought an Apple AirPort Extreme and connected it's WAN port to the modem. Now everything works just perfectly, but the AirPort configuration utility…
Ivan
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NAT vs. port forwarding

Possible Duplicate: What is port forwarding and what is it used for? What is the difference between NAT and port forwarding? Are they two different names for the same thing? What would be a short practical example?
Bunkai.Satori
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Set up a web server behind a Carrier Grade NAT

I was trying to set up a small home server. I use dynamic IP adress. My router's wan adress is like this 100.70.81.xxx and my public ip is 81.213.177.xx I made port forwarding in my router. www, smtp and pop3 ports are open. But still my server is…
user779261
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6 answers

Is it possible to see my external IP address without making an outbound web request?

If your connection is NAT'ed, is it possible to see your external IP address without making an outbound web request? Any OS (Windows, Linux, etc.) is fine.
Axel Persinger
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NAT and UDP replies

Sanity check please. If I send UDP packets from Machine A behind a NAT to Machine B's port N, where Machine B is outside the NAT (elsewhere on the Internet), can I reasonably expect that NAT to pass UDP packets received from Machine B on port N back…
tomfanning
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ssh through a router without port forwarding

I have a linux server, and I want to put it in a home network behind a router. I need to ssh to this server sometime from outside, but I don't want to set up port forwarding because I don't have access to the router, and I don't know the ip of the…
Jiechao Li
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How does the router know which device to send packets to?

my question does not concern how it moves through the internet, but how it moves through the router to a certain device. All devices connected to a router in a home network have the same external IP. Say device A is loading a page and packets are…
Dan Webster
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