Why does my SG3 keep using a different IPv6 address all the time?

banjo67xxx

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[SOLVED] Why does my SG3 keep using a different IPv6 address all the time?

Hi all,

As part of the IPv6 standards for neighbour discovery devices append a 64bit host address to the network supplied prefix, and the host address is normally based upon their mac address an a pre-defined way. However, the IPv6 addresses my SG3 has been using bear no relationship to its mac address, and in the 4 weeks I've owned it I've so far noticed its had atleast 4 different IPv6 host addresses on my network.

Why is this?

Has Samsung decided to protect our anonymity by ensuring the device's final 64 bits are random as we move from home to work to hotspot?

Regards,
Banjo

PS: My SG3's mainboard failed after only 30 days, so dont ask me to check any settings until Vodafone UK have replaced it under warranty :(
 
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Trees

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Is your network configured to provide or honor the last used address that your S3 had? I know this may not help with non-correlation between the S3's MAC address and the standards you've described, but may be one thing to look into.
 

banjo67xxx

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Is your network configured to provide or honor the last used address that your S3 had?

My network will accept any IPv6 address within the /64 subnet and provides the /64 prefix by nd, so yes it honours every address the SG3 uses. The only restriction is MAC address filtering by the Wifi AP.
 

Trees

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I see. I was thinking of IPv4 feature that typically returns the same last used IP address to a requestor. I don't have IPv6 enabled on my home network so unfortunately not able to test anything. It's an interesting situation. Perhaps some of the developers on XDA might have some thoughts?
 

MrDoh

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Did IPv6 just work for you on wireless (WiFi)? I have enabled IPv6 on my home network, and it works with everything except my S3 phone. Both my iPad and and my wife's iPhone are fine with IPv6, as are our desktop and laptop computers, but the IPv6 test says on my S3 returns:

"No IPv6 address detected"

so I gather than my S3 is not configuring itself for IPv6.

So I'm wondering if you had to do anything to get your phone to even configure itself for IPv6?

Thanks.
 
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banjo67xxx

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So I'm wondering if you had to do anything to get your phone to even configure itself for IPv6?
No - nothing special

My iPhones iPads laptops and servers all connect immediately without any problems to my IPv6 network. The only issues I have are
1) Solaris virtual machines needed to manually define a link-local address
2) I cant get the SG3 to use IPv6 over VPN even with use-ipv6 configured in the ppp profile on my router
3) about 25% of the time my SG3 fails all IPv6 tests on Test your IPv6. when directly on my home network
And ofc
4) this issue in that it keeps changing the last 64bits of its IPv6 address

Banjo
 
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Trees

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No - nothing special

My iPhones iPads laptops and servers all connect immediately without any problems to my IPv6 network. The only issues I have are
1) Solaris virtual machines needed to manually define a link-local address
2) I cant get the SG3 to use IPv6 over VPN even with use-ipv6 configured in the ppp profile on my router
3) about 25% of the time my SG3 fails all IPv6 tests on Test your IPv6. when directly on my home network
And ofc
4) this issue in that it keeps changing the last 64bits of its IPv6 address

Banjo

Not to dismiss or trivialize the problem, but is it possible to use IPv4 for your S3? May be the easiest option to get the S3 to reliably connect on WiFi.
 

banjo67xxx

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Not to dismiss or trivialize the problem, but is it possible to use IPv4 for your S3? May be the easiest option to get the S3 to reliably connect on WiFi.
I can see your point. Yes thanks, IPv4 works perfectly, and has done since day 1.

Since I've gone to the trouble of buying an IPv6 capable router and getting a 6to4 tunnel, it would be nice if all my devices used it consistently.
 

banjo67xxx

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I've since discovered what's happening, and it is working as designed.

The SG3 is simply implementing RFC4941 IPv6 Privacy Extensions to protect my anonymity when moving between home, work, and public hotspots. Without the use of RFC4941 then anyone could easily track my movements by following the SG3's 64-bit host address between networks.

If I want to I can still connect directly to the phone using its fixed (mac-address derived) ipv6 host address then I can. Its just that it wont use this address by default for outbound connections to protect my anonymity.
 

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