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Ylli F
Posted 2014-03-18T19:32:26.357
Reputation: 121
Why am I seeing multiple different IP addresses reported as my public IP?
Answers
10
You don't seem to have a public IPv4 address at all. Your ISP has several public addresses that it uses to NAT outbound connections from its users. In such a situation a user (i.e. you) doesn't get a public address and can therefore not accept any inbound connections for e.g. you camera. Your internet connection is outbound-only.
This is something people will have to get used to. The world is running out of unassigned IPv4 addresses, so sharing IPv4 addresses amongst multiple customers will become the norm. Technologies such as Carrier Grade NAT (NAT at the ISP level) and DS-Lite (NAT at the ISP level where IPv4 traffic is tunnelled over IPv6) will be outbound-only. Running your own service (web, camera, mail) will be impossible on such connections. If MAP is used (no NAT at the ISP level, IPv4 addresses are shared and a user gets a number of UDP and TCP ports) the user can use the given ports for NAT and inbound services.
The only way to keep the internet 'open' so that everybody has full connectivity, for inbound and outbound connections using whatever protocol they want, is to use IPv6. The world is slowly moving in that direction. If you look at Google's IPv6 statistics you can see that IPv6 adoption is growing exponentially.
If you run into problems such as described in this question the best thing you can do is to push for IPv6 adoption everywhere: your home ISP, your mobile provider, your office etc. Otherwise we'll end up in a situation where e.g. having a home camera reachable from the internet will become technically impossible.
Sander Steffann
Posted 2014-03-18T19:32:26.357
Reputation: 4 169
Thank you very much for this great explanation. I guess I don't have any other alternative but to look for another ISP, or wait for IPv6, which I think will take at least a decade to get here(based on that Google's IPv6 stats for Europe)! – Ylli F – 2014-03-19T09:16:34.487
4Don't wait for IPv6: push and complain to get IPv6. ISPs need to see that their customers want and need IPv6 to make them act. – Sander Steffann – 2014-03-19T11:16:08.213
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You could be behind a carrier-grade NAT (CGN) with an "IP address pooling" behavior of "Arbitrary", rather than the recommended behavior of "Paired". See http://tools.ietf.org/html/rfc4787#section-4.1 .
Or you could be behind a transparent HTTP proxy that causes similar problems, but only for HTTP.
Spiff
Posted 2014-03-18T19:32:26.357
Reputation: 84 656
1Hmmm I'm not that familiar with those terms so thanks for the link. PS: Could this also be the cause why I'm not being able to remotely connect to my IP camera? – Ylli F – 2014-03-18T20:14:52.083
1Yes, @YlliF, apart from other problems like modem NAT settings: if your IP address changes that rapidly, then many other subscribers are using the same set of IP addresses. So, trying to connect to your computer will then actually try to connect to someone else most of the time. (If the provider doesn't actually somehow block it to start with.) – Arjan – 2014-03-18T20:20:31.700
1@Arjan I think it blocks it at the beginning because I could never remotely connect to my computer from another device, nor check my IP camera. Thanks. – Ylli F – 2014-03-18T20:31:24.003
YlliF - Check out a service called dynamic DNS if you want to be able to connect back to your computer remotely or connect to your camera no matter what IP address you are showing up as having publicly. You will have to download a client to your computer (your camera might support Dynamic DNS as well, i'd check the config) and it keeps track of whatever public IP you are assigned and will map it to a much easier to remember hostname. – Richie086 – 2014-03-18T22:23:42.963
2@Richie086 You see howrapidly the IP addresses change? How do you think that would work? – glglgl – 2014-03-19T08:05:26.920
@Richie086 Yeah you're right, camera has Dynamic DNS, but it loads nothing, even after forwarding camera port on router! This situation has made my camera useless! Thanks. – Ylli F – 2014-03-19T08:11:09.047
1@YlliF Right. The NAT that's being performed by your ISP is actually rather similar to the NAT that your router performs. A request can't really come into you, without going out first. So if you forward at the router level, it's still happening at the ISP level. – Cruncher – 2014-03-19T14:47:08.267
Do they show that at the same time or over a longer period? – TheUser1024 – 2014-03-18T19:37:01.143
3At the same time. – Ylli F – 2014-03-18T19:38:38.657
What is your setup (device, network)? Is there a router and do you have access to it? Consider editing your question instead of commenting. – TheUser1024 – 2014-03-18T19:43:44.687
It's Motorola Cable Modem - Netgear Wireless Router. Thanks. – Ylli F – 2014-03-18T19:46:16.957
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Take a look at this post.
– None – 2014-03-18T19:46:27.8801Ylli F, What is your ISP (internet provider)? "KujtesaNET"? Looks like they have NAT with several global IP addesses and all requests from you are dynamically balanced between several public IPs. – osgx – 2014-03-18T19:54:00.180
Note that refreshing one of those might show a different address too. (Though it might take some time to see that.) – Arjan – 2014-03-18T19:54:55.820
@osgx Yeah, you're right, that's my ISP, "KujtesaNET". – Ylli F – 2014-03-18T19:56:46.697
@Arjan Well, yeah I remember two days ago, it was 46.19.227.249 – Ylli F – 2014-03-18T19:58:31.133
As an aside: if the addresses change rapidly, that might get you unexpected problems.
– Arjan – 2014-03-18T20:02:55.373@Arjan Yeah and the most I hate, is that I can never use most of the sites to download things because it shows msgs like your IP is blacklisted or made too many server requests from your IP and so on... While in fact it was the first time being there! – Ylli F – 2014-03-18T20:13:54.210
Use http://icanhazip.com/.
– evamvid – 2014-03-19T00:21:13.380@evamvid Now's 46.19.227.255 – Ylli F – 2014-03-19T08:05:46.813