Local Network Protection for IPv6
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Since some people seem to think NAT on IPv6 is a good idea, I'm linking to this RFC to show why it's not. NAT was created to get around the IPv4 address shortage, but causes other problems. It should not be used on IPv6.
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Since some people seem to think NAT on IPv6 is a good idea, I'm linking to this RFC to show why it's not. NAT was created to get around the IPv4 address shortage, but causes other problems. It should not be used on IPv6.
There is a place for NAT with ipv6 and that's VPNs. My service provider NATs both the ipv4 and the ipv6 addresses. On top of that, the addresses are shared. If you don't NAT ipv4 and ipv6, you don't have privacy. Sharing addresses adds to privacy.
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Since some people seem to think NAT on IPv6 is a good idea, I'm linking to this RFC to show why it's not. NAT was created to get around the IPv4 address shortage, but causes other problems. It should not be used on IPv6.
There is a place for NAT with ipv6 and that's VPNs. My service provider NATs both the ipv4 and the ipv6 addresses. On top of that, the addresses are shared. If you don't NAT ipv4 and ipv6, you don't have privacy. Sharing addresses adds to privacy.
That's bizarre! Why would any ISP NAT IPv6? There's no address shortage with IPv6. In fact, there are enough /48 prefixes to give 5000 to every person on earth! I get a /56 or 256 /64s from my ISP. It's a simple matter to assign one of the /64s to a VPN.
One thing that provided privacy are the privacy addresses (wonder why they're called that?), where outgoing connections get a new address every day. Also, that RFC I linked to mentions that the sparse address space makes scanning attacks difficult. It said that with a 40 Gb connection, it would take 5000 years to ping an entire /64.
NAT is still a bad idea. While it was needed to get around the IPv4 address shortage, it also causes problems for some protocols and increases the work routers have to do. It has no place in IPv6.
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Since some people seem to think NAT on IPv6 is a good idea, I'm linking to this RFC to show why it's not. NAT was created to get around the IPv4 address shortage, but causes other problems. It should not be used on IPv6.
There is a place for NAT with ipv6 and that's VPNs. My service provider NATs both the ipv4 and the ipv6 addresses. On top of that, the addresses are shared. If you don't NAT ipv4 and ipv6, you don't have privacy. Sharing addresses adds to privacy.
That's bizarre! Why would any ISP NAT IPv6? There's no address shortage with IPv6. In fact, there are enough /48 prefixes to give 5000 to every person on earth! I get a /56 or 256 /64s from my ISP. It's a simple matter to assign one of the /64s to a VPN.
One thing that provided privacy are the privacy addresses (wonder why they're called that?), where outgoing connections get a new address every day. Also, that RFC I linked to mentions that the sparse address space makes scanning attacks difficult. It said that with a 40 Gb connection, it would take 5000 years to ping an entire /64.
NAT is still a bad idea. While it was needed to get around the IPv4 address shortage, it also causes problems for some protocols and increases the work routers have to do. It has no place in IPv6.
If you read what I said, I was referring to a VPN service provider, not my ISP. And irrespective of how many address supported by ipv6, if you are using the prefix allocated by your ISP, it's directly traceable to you, no different than your ipv4 address. VPN service providers that offer dual-stack service provide their own public ipv4 and ipv6 addresses to be exposed to the world. That way if you do "what is my ip address", it will show shared addresses belonging to the VPN service provider in whatever location their gateway is, not an address allocated using the prefix that was assigned to you by your ISP. Even privacy addresses do not accomplish this. They are also allocated using your dedicated prefix.
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I think the privacy address issue is causing confusion…
If the type of privacy you are looking for is preventing subnet scanning, it is already "built-in", because it would take forever to scan a /64, and a firewall would block it anyway. It really doesn't matter what address you assign to the host "privacy" or static, or DHCP6, or SLAAC.
Since the privacy address changes from time-to-time, you're not really getting privacy because any website can easily track you using cookies, beacons, etc instead to figure out who you are anyway, so the address is really irrelevant. Facebook, Google and their advertising machines have this technique pretty well in the bag.
On the flip-side, due to the huge IPv6 address space, anti-hacking blocking techniques are turning to tracking prefixes, for instance they would block the /64 of a host doing bad stuff, and then work up to bigger and bigger subnets if the problem persists, because there isn't enough machine resources to keep track of individual IPs.If you are concerned about privacy to the point that you are using PIA (VPN) services, then you must ensure that you never have, nor ever will access anything without the VPN active, as a single dropped cookie will allow correlation between your "real" prefix and whatever prefix the PIA service is giving out to you. Besides, the NSA et al. have already figured out how to do that.
In fact, just don't deploy IPv6 if a tin-foil hat is part of your wardrobe!
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I think the privacy address issue is causing confusion…
If the type of privacy you are looking for is preventing subnet scanning, it is already "built-in", because it would take forever to scan a /64, and a firewall would block it anyway. It really doesn't matter what address you assign to the host "privacy" or static, or DHCP6, or SLAAC.
Since the privacy address changes from time-to-time, you're not really getting privacy because any website can easily track you using cookies, beacons, etc instead to figure out who you are anyway, so the address is really irrelevant. Facebook, Google and their advertising machines have this technique pretty well in the bag.
On the flip-side, due to the huge IPv6 address space, anti-hacking blocking techniques are turning to tracking prefixes, for instance they would block the /64 of a host doing bad stuff, and then work up to bigger and bigger subnets if the problem persists, because there isn't enough machine resources to keep track of individual IPs.If you are concerned about privacy to the point that you are using PIA (VPN) services, then you must ensure that you never have, nor ever will access anything without the VPN active, as a single dropped cookie will allow correlation between your "real" prefix and whatever prefix the PIA service is giving out to you. Besides, the NSA et al. have already figured out how to do that.
In fact, just don't deploy IPv6 if a tin-foil hat is part of your wardrobe!
Not sure who your "tin-foil hat" comment is directed at. In case it wasn't clear, my point is that an ipv6 privacy address will be allocated from within the same prefix as the UGA, so it's directly traceable to a subscriber in exactly the same manner as an ipv4 address and the location will be associated accordingly. If you're using a dual-stack vpn for whatever reason, be it "privacy" or geolocation, you want both addresses to be associated with the physical location you chose for the exit point. That way, you will see content for the chosen location, not for your home location, and if you're downloading a torrent over ipv6 (which may happen if you have a dual-stack vpn connection), the apparent address will be the public address of the exit point, not your own UGA or privacy address. A VPN is a very handy way to get around the silly "this content is not available in your location" message for this reason. While a VPN may not fool the NSA, it certainly works for geolocation. It would completely defeat the purpose of using a VPN to not "NAT" both the ipv4 and ipv6 addresses. Some day, when people no longer use ipv4, there will still be VPNs and they will still NAT the ipv6 address, otherwise, what's the point?
Anyone really concerned about privacy from the NSA should be using tor.
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If you read what I said, I was referring to a VPN service provider, not my ISP.
I guess I misread "My service provider NATs both the ipv4 and the ipv6 addresses." because you didn't say you got a VPN from a service provider. I have set up several VPNs in my time and never used a service provider.
Regardless, where does NAT fit in with your description? You could use Unique Local Addresses for the VPN, just as you'd use RFC 1918 addresses on IPv4. Neither requires NAT. What address range does the VPN service supply? They could have a public /48 or other suitable prefix and assign a /64 on a temporary basis to users. I believe that was also mentioned in that RFC.
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as a single dropped cookie
Yeah, you don't want to toss your cookies! ;)
In fact, just don't deploy IPv6 if a tin-foil hat is part of your wardrobe!
Or IPv4 for that matter.
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If you read what I said, I was referring to a VPN service provider, not my ISP.
I guess I misread "My service provider NATs both the ipv4 and the ipv6 addresses." because you didn't say you got a VPN from a service provider. I have set up several VPNs in my time and never used a service provider.
Regardless, where does NAT fit in with your description? You could use Unique Local Addresses for the VPN, just as you'd use RFC 1918 addresses on IPv4. Neither requires NAT. What address range does the VPN service supply? They could have a public /48 or other suitable prefix and assign a /64 on a temporary basis to users. I believe that was also mentioned in that RFC.
If I pay a company to provide a service, it is a service provider, IMO. An ISP is a service provider, but not all service providers are ISPs.
When I'm connected "through" Telus (i.e., without the VPN connected), my public ipv4 and ipv6 addresses are the assigned ipv4 and a UGA allocated using the assigned ipv6 prefix. They are "traceable" to me, subject to how well Telus maintains logs. When I connect to the VPN service, I can choose from their list of servers which are located around the world. Each server provides different ipv4 and ipv6 addresses, both of which are shared. Depending on the location of the server a different "service provider" is used. I don't choose the addresses. They are assigned when the client connects to the server. The computer sees private ipv4 and ipv6 addresses, but when you use a website like ipv6-test.com, only the public addresses are visible. When I'm connected, I get ads in the local language. It's as if I'm in the location connected using the particular local service provider. The addresses are NATed between private and public by the VPN server. This is how typical VPN services such as PIA or whatever work. If you set up your own VPN server, it's going to be using your ipv4 address and ipv6 prefix. Such a VPN isn't very useful if you are trying to spoof your location or have addresses that aren't traceable to you.
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Hiding behind a vpn providers IP range has ZERO to do with natting the ipv6 address they give your client.. With the almost infinite address space that ipv6 provides there is zero reason for them to NAT this ipv6 address they give the vpn client..
They would use a tunnel network just like you do in ipv4. The only reason the tunnel network in ipv4 is normally rfc1918 is the vpn provider doesn't have a shitton of ipv4 public space to use ;)
There would be ZERO reason for a ipv6 vpn provider to NAT this address space to hide their users real IPv6 address.. To the public the IPv6 address these users come from would still be registered to the VPN provider.. The ipv6 address your traffic presents to the world would be theirs, and not registered to you or your ISP in anyway.
The only reason you share IPs in the IPv4 world is their is lack of them!!!
As to the vpn tracking which user tunnel IP is what public IP would be to the vpn provider logging.
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As to the vpn tracking which user tunnel IP is what public IP would be to the vpn provider logging.
And via tossed cookies. :P
Not sure who your "tin-foil hat" comment is directed at.
Not directed at anyone in particular, but generally to people that think that casually using a PIA offers them anonymity.
I get it, people just want to use torrents and not receive threatening legal letters, but my point is that if you are serious about achieving a true level of anonymity, you first need to ensure that your anonymous environment cannot ever connect to anything without going through a VPN. You need to select PIA providers that don't keep logs and you need to change your ISP and PIA providers from time-to-time. You need to setup machines that will be accessing the Internet anonymous from scratch and from trusted sources, and you need rebuild them from time-to-time, or use a read-only machine VM instance. And you better be aggressively blocking Google, Facebook, Twitter and all other social media services. You must use all new accounts anonymously. You need to study movies like "Enemy of the state", and "The Conversation", and on and on and on….The required effort is huge, and you must never make a mistake. :-X
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As to the vpn tracking which user tunnel IP is what public IP would be to the vpn provider logging.
And via tossed cookies. :P
Not sure who your "tin-foil hat" comment is directed at.
Not directed at anyone in particular, but generally to people that think that casually using a PIA offers them anonymity.
I get it, people just want to use torrents and not receive threatening legal letters, but my point is that if you are serious about achieving a true level of anonymity, you first need to ensure that your anonymous environment cannot ever connect to anything without going through a VPN. You need to select PIA providers that don't keep logs and you need to change your ISP and PIA providers from time-to-time. You need to setup machines that will be accessing the Internet anonymous from scratch and from trusted sources, and you need rebuild them from time-to-time, or use a read-only machine VM instance. And you better be aggressively blocking Google, Facebook, Twitter and all other social media services. You must use all new accounts anonymously. You need to study movies like "Enemy of the state", and "The Conversation", and on and on and on….The required effort is huge, and you must never make a mistake. :-X
I think I was pretty clear that I'm not trying to achieve privacy from NSA or I would be using tor and resorting to the other measures you mentioned. I use a VPN for two purposes. First is geolocation. Second is for torrenting. For these purposes, it works as advertised. My vpn service provider does not log. I'm happy.
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When you get an IPv6 VPN, what address range is it in? If it starts with 2, then it's a public address that's given to you to use and does not need NAT. If it starts with fd, then it's a Unique Local Address that requires NAT.
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Hiding behind a vpn providers IP range has ZERO to do with natting the ipv6 address they give your client.. With the almost infinite address space that ipv6 provides there is zero reason for them to NAT this ipv6 address they give the vpn client..
They would use a tunnel network just like you do in ipv4. The only reason the tunnel network in ipv4 is normally rfc1918 is the vpn provider doesn't have a shitton of ipv4 public space to use ;)
There would be ZERO reason for a ipv6 vpn provider to NAT this address space to hide their users real IPv6 address.. To the public the IPv6 address these users come from would still be registered to the VPN provider.. The ipv6 address your traffic presents to the world would be theirs, and not registered to you or your ISP in anyway.
The only reason you share IPs in the IPv4 world is their is lack of them!!!
As to the vpn tracking which user tunnel IP is what public IP would be to the vpn provider logging.
When I go to ipv6-test.com while the vpn is not connected, it shows both addresses are from my isp. When I go to ipv6-test.com while the vpn is connected, it shows both addresses are from the local service provider where the vpn server is located. These addresses are shared. When my pc is connected to the vpn, it has private ipv4 (10…) and ipv6 (fdda::...) addresses according to ipconfig. The vpn connection is NATing the private addresses to the shared public addresses. Maybe they could or should have set it up differently, but as far as I'm concerned, it works, so that's good enough for me.
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When my pc is connected to the vpn, it has private ipv4 (10…) and ipv6 (fdda::...) addresses according to ipconfig. The vpn connection is NATing the private addresses to the shared public addresses. Maybe they could or should have set it up differently, but as far as I'm concerned, it works, so that's good enough for me.
Yes they should have done IPv6 differently. By using a Unique Local Address, they're forcing NAT to be used, with all it's problems. With all the IPv6 addresses available, they could have used a public address and avoided NAT. I don't know how many addresses they give you, but a single /64 has 2^64 addresses available. That's the entire IPv4 address space squared!
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When my pc is connected to the vpn, it has private ipv4 (10…) and ipv6 (fdda::...) addresses according to ipconfig. The vpn connection is NATing the private addresses to the shared public addresses. Maybe they could or should have set it up differently, but as far as I'm concerned, it works, so that's good enough for me.
Yes they should have done IPv6 differently. By using a Unique Local Address, they're forcing NAT to be used, with all it's problems. With all the IPv6 addresses available, they could have used a public address and avoided NAT. I don't know how many addresses they give you, but a single /64 has 2^64 addresses available. That's the entire IPv4 address space squared!
No one is questioning that there are 2^64 addresses available in a /64 prefix. However, shared public addresses are considered a feature, because they further obscure individual users. There's no way to share public addresses without translating the individual private addresses to the shared public address. NAT or not, the vpn works. I can max out my available bandwidth and it does exactly what I want.
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"There's no way to share public addresses without translating the individual private addresses to the shared public address"
Not really true - you could quite easy use a proxy to have multiple users traffic be coming from the same public IP without any actual nat.
Also with ipv6 done how its designed, outbound traffic from a client would use multiple IPs all the time.. These Temporary Addresses would expire and new ones created all the time. So the odds of someone tracking a users actions based upon their IPv6 would be quite difficult because they would use different address all the time for their different connections, and one session might use address X while traffic to some other place would come from address Y.
Really the whole point of NAT as a feature to hide someones behavior is gone with the privacy extensions that are built into ipv6. So while someone would be able to track your IPv6 address to the ISP providing you said address, unless the isp is giving away your info there would normally be no way for someone to know who that IPv6 address is actually registered too. So you trust the vpn provider more than the isp in giving away said info. Or your wanting to use the vpn to hide your behavior from your ISP.
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These Temporary Addresses would expire and new ones created all the time.
Quite so. On my Linux system, I get a new privacy address every 24 hours and they have a lifetime of only 5 or 6 days. Compare that to the 5000 years it would take to scan a single /64, with a 40 Gb connection, according to the RFC I referenced for this thread.
Getting back to the VPN, if a service provider simply provided temporary use of a single address in a /64 for the VPN, then the user would be just as hidden as behind NAT.
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You're both missing the point and getting hung up on semantics. Irrespective of whether "NAT" or a proxy server or some other mechanism is used, a reasonable expectation from a vpn service provider is for to provide public addresses that are not associated with the isp-provided addresses or prefix. The mechanism used to achieve that is immaterial. According to my vpn service provider, "NAT" is being used in their openvpn configuration. They could use magic, as long as they accomplish the same result. It makes no difference.
I attached three screen captures.
The first is the result of ipv6-test.com when the vpn is not connected. It's possible to determine my isp and my approximate location. The address is the privacy address, not the dhcpv6 address. Both the ipv4 address and the ipv6 prefix are directly associated with me.
The second is output from ipconfig /all with the vpn connected. You can see the private addresses used by the vpn, as well as the public addresses used when the vpn is not connected. (This screen capture was taken at a different time so the privacy address is not the same as above.)
The third is the result of ipv6-test.com when the vpn is connected to a server in sweden. It shows the isp the vpn server is connected to and it shows the location in sweden. If I browse to a website, I see local ads in the swedish language. I get local ads for whatever server I connect to. I can view regional content that would otherwise be "not available in my location".
This is exactly what I would expect a vpn to do. It completely defeats the purpose of a vpn if the public ipv6 address uses my isp-provided prefix.
The issue of whether I trust my vpn service provider more than my isp is somewhat moot, because my isp cannot / will not offer public ip addresses in another geographic location. However, since you bring up trust, my vpn service provider keeps no logs and they have no record of my name or my email address. My isp clearly has that info and more. I completely trust my isp to act in its self-interest. They have my contact info and I don't doubt they would provide it if they were compelled. My vpn service provider has nothing to give, even if it's compelled. For me, this is a big deal, but not nearly as big a deal for me as it is for a person who lives in a country where there is censorship, such as China or Iran.
In the (distant) future when isps stop handing out ipv4 addresses, people will still be using vpns for a variety of reasons. A vpn that uses a privacy address allocated using the subscriber's isp-provided prefix is an oxymoron and would serve no purpose. It's neither virtual, nor private. I don't get why you're beating on this dead horse. A privacy address has a valid purpose, but it's not equivalent to a vpn.
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You're both missing the point and getting hung up on semantics. Irrespective of whether "NAT" or a proxy server or some other mechanism is used, a reasonable expectation from a vpn service provider is for to provide public addresses that are not associated with the isp-provided addresses or prefix.
And once again, there is no need to use NAT to do that. Any VPN provider can get a block of global addresses and hand them out as needed, on a temporary basis to their users. That address will be one of theirs, not yours and can be different every time you connect or even changed periodically.
