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ISP Deployed NAT


I am new here and have really been struggling the past few days with figuring this out. I'll just cut right to it

My internet connection is supplied from a small ISP that uses wireless technology to distribute internet to the rural area where Telus and Shaw do not accommodate. I live in a remote area in British Columbia, Canada.

There is a CAT5 cable that runs from the dish/receiver thing to a POE adapter then another CAT5 cable that leaves the adapter and runs to my Linksys EA2700 router. On my router I have configured ports to be forwarded for things like PSN, Steam, XboxLive, and a small VB6 game server that I run as a hobby for my friends and I. Recently these ports quit forwarding, and I did not know why. I think it is important to know that these ports were working before, without issue.

After some research I discovered that my WAN IP on my router is an IPv4 address ( which is also a private address. I am not sure what the IP was before the ports stopped forwarding, the first thing I did was reset the router, perhaps a new IP was assigned? So I decided that my ISP has me behind some sort of NAT. So with this information I called my ISP and had a quick discussion. He told me I am behind a very complicated double NAT'd network and when I asked about his NAT he said it is in bridge mode. But from what I have read, if that were true, I wouldn't be having these issues and would not be assigned a private IP address.

The next thing I found out about is CGNAT/NAT444/LSN.

My question to you guys, is what can I do? He seems very understanding and offered to give me a static IP but didn't say anything about a public IP. Is there something I can go to him with, some better information, or questions? Some way of describing what I need to have happen or want him to do? Is it possible to have in assign me a static IP address and push me through as demilitarized?

I am basically just looking for advice and the ISP owner seems to be willing to help me out.



Find out what the static range is. It's possible that it is an external range.

I worked for an ISP awhile back and for a segment of our customers (which we inherited from a regional cable provider) we had them NAT'd, but we did have an external static range we could assign them.


Cortland, NY
reply to MrAnthony

Double NAT breaks a lot of things. I can't VPN over most double NAT'd network.

Montreal, QC
reply to MrAnthony

Double nat doesn't break much if properly configured. I've used double NAT, and as long as you forward the port on both routers, it works fine. Including VPNs. In fact, excepting wierd protocols like GRE, I can't think of why anything would work with regular NAT but not with double NAT...
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Kansas City, MO
reply to MrAnthony

said by MrAnthony :

and offered to give me a static IP but didn't say anything about a public IP.

I think the static IP will be a real routable IP address... he woulndn't mention it otherwise (that is a static internal IP would still be an internal IP).

Another trick you can use is to get a VPN internet service provider and punch out that way... then you will have a real IP at the end of the VPN tunnel.



Thanks a lot for all the replies

I have attempted to use a VPN service before, albeit a free one, and never had much luck... I've written the ISP owner an email to see if he will be willing to give me a static IP address and see what happens from there. Hopefully this will work!


reply to Guspaz

There isn't much point in doing port forwarding on a router with a private IP address, unless you can somehow convince your ISP to forward some ports to you in the first place.

Montreal, QC

Right, I was disputing the claim that double NAT breaks things, not the claim that ISP NAT breaks things.



said by Guspaz:

Right, I was disputing the claim that double NAT breaks things, not the claim that ISP NAT breaks things.

And your reply was based on assuming a particular environment where the user has control of both NAT devices which won't be the case and in most cases isn't the case when there is double NAT. The claim is still true.


Ottawa, ON
reply to MrAnthony

Your isp doesn't give you a public ip because they most likely don't have any and are reselling consumer internet. You can check your external ip here »ifconfig.me/ then you can usually see the isp in the remote host string, or you can see who owns the ip range here »whois.arin.net/ui . A VPN can fix your problem but it's a complicated to setup and would most likely increase latency and lower speed a bit.


reply to MrAnthony

Most likely, you're using Motorola Canopy equipment, which is, by design, NAT'd. Most things are firewalled, as a result. This gives ISP's the chance to sell a value-added product to you - a static IP. To allow the IP to work, the modem will have to be bridged, which the ISP can do. Often, its scripted into the management software they use. They sell you a static IP, bridge the modem, and you get your routable public IP. I am pretty convinced that it'll work for you.