[IPv6]Re: New draft: "The IPv6 Loopback Address Prefix"

[Brian E Carpenter <[e-mail]>]

On 03-Dec-25 19:04, Sebastian Moeller wrote:
> Respectfully,
> 
> You seem to be arguing for even more operational differences between 4 and 6 here. 

I don't think so. I think Bob's argument is just another version of "almost any address range would work for this purpose; it doesn't have to be special."

The main difference from IPv4 is that we have plenty of address ranges we could choose. And of course in both cases we can invent as many virtual interfaces as we need.

> No matter how backward we consider v4 to be, this would introduce additional friction for uses having the pleasure having to deal with both v4 and v6, is that really worth it?

What's the friction? Once you picked (say) a /96 to use, the algorithm would be identical, wouldn't it, apart from a longer prefix?

    Brian

> 
> 
> On December 2, 2025 6:52:01 PM GMT+01:00, Bob Hinden <[e-mail]> wrote:
> 
>     Warren,
> 
>     Two thoughts.
> 
>     Chair hat on: I agree that this should belong to 6MAN.
> 
>     Individual hat on: The question I have is about using loopback addresses for virtual host addresses. What was done with in IPv4 always seems to me like a “hack”. Probably because of IPv4 limitations. We don’t have these limitations in IPv6 and I wonder if that is the right to replicate what was done in IPv4 in IPv6.
> 
>     We could leave the IPv6 loop back address alone (that is, use it for loopback), and define a new set of IPv6 virtual host addresses. It doesn’t seem to me that it has anything to do with a loopback function.
> 
>     Further, there are a lot of possibilities for what to use for this, especially given the trend to allocate a prefix to a host. Even without that an IPv6 node can have many addresses.
> 
>     Bob
> 
> 
> 
>         On Dec 1, 2025, at 12:02 PM, Warren Kumari <[e-mail]> wrote:
> 
>         [ - V6OPS, +6MAN Chairs ]
> 
>         Dear 6MAN chairs,
> 
>         The authors would like to request adoption of this document.
> 
>         It is clear that there is still work needed before the document is ready
>         for publication, but it's also clear that there is significant interest in
>         the topic.
> 
>         It would be helpful for the document to have a designated home - I had
>         originally CCed V6OPS, and there has been significant discussion there too.
> 
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