This has been migrated from Basecamp 2 at https://basecamp.com/2341283/projects/12196005/todos/286523067#comment_613610709

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We left off at there being an issue where the last 4 blocks of digits in an IPv6 address seem to change over time.

As an example, we tested Morgan's address of 2001:569:7bb6:f200:e19c:e3cc:16df:29d7 which then changed to 2001:569:7bb6:f200:3560:77b7:4420:d316.

Note that the bolded blocks above remained the same. We should investigate if these values never change per network.

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Carbon60 had provided us with some additional information about IPv6:

"Although it is tailored to Apple’s platforms, it has a good overview of how IPv6 networking is interacting with traditional IPv4, which might be helpful.
 
From our discussion it sounds like what might be happening with the final two blocks of the addresses is that the IPv6 addresses may not be as static as the IPv4 on the network, possibly at the ISP level.
Although a user connecting to the app might have a static IPv4 address from their ISP, the IPv6 address is likely generated by being translated through a NAT64 gateway. (See Figure 10-2 in the above linked document)
In essence, the IPv4 might be static but their IPv6 is actually being generated programmatically from a gateway and the final two blocks change depending on what the gateway has available when the connection is established.
 
Does this make sense? We may be able to help some more if we had more details."

Thanks Ryan .

Anil , as you can from the above, we still don't have an handle on how to properly deal with IPv6 ranges. Please review, and let us know if you have any suggestions on next steps.

Morgan 

Hi Anil and Morgan

I was working in Google Analytics today and noticed how they handle IPv6 addresses.

See https://support.google.com/analytics/answer/1034840

Below is their example for entering IPv6:

Screen Shot 2018-05-02 at 4.13.00 PM.png 11.5 KB • Download

Hi Ryan ,

I didn't see the example used for your screenshot in the link. Could you clarify what's these page explain via IPv6? Does it mean there is a way to identity a static IPv6 addresses for white listing purpose? Also, can we identify ranges?

Thanks,

Morgan

Hi Ryan ,

Now that we're starting to get near the end of the maintenance to-do list, could we plan on discussing IPv6 again tomorrow. Perhaps we could start by explaining the GA article you posted above. I wasn't able to find anything that clarified how we can consistently identify an IPv6 addresses for the purposes of IP authentication.

Thanks,

Morgan 

We've decided to leave the functionality as is and will revisit if clients request access.