Re: IPv6 prefix lengths - how long?

Alexandre Petrescu <alexandre.petrescu@gmail.com> Sat, 15 June 2019 15:05 UTC

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Subject: Re: IPv6 prefix lengths - how long?
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From: Alexandre Petrescu <alexandre.petrescu@gmail.com>
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Date: Sat, 15 Jun 2019 17:05:34 +0200
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Le 07/06/2019 à 19:43, Templin (US), Fred L a écrit :
> Hi, we all know about the tussle regarding the /64 boundary for IPv6
>  prefixes but
> 
> assuming that we will one day want to allow longer prefixes the
> question is “how long”?
> 
> We all know about /127 for point to point links, but I am not talking
>  about those. I am
> 
> talking about prefixes that are assigned to nodes that might be
> acting either as routers
> 
> or as multi-addressed hosts.
> 
> Because of RFC7934, we see the value of Host Address Availability 
> Recommendations.
> 
> It makes the point that, due to the nature of multi-addressing
> supported by IPv6, it
> 
> would be useful for each node to be able to configure multiple
> (perhaps even many)
> 
> IPv6 addresses from an IPv6 prefix. But, “how many”?
> 
> My assertion is that a multi-addressed host (or, an End User Network
>  router) should
> 
> support numbering for at least 1K IPv6 addresses. This would imply
> that (assuming
> 
> at some point the /64 boundary is relaxed) the longest IPv6 prefix 
> should be a /118.
> 
> Thoughts?

I think the answer to the question 'how many' is related to the L2 
technology.

On WiFi we know it is about 100 or less laptops attached to an Access 
Point.  Some APs limit that to 4.  Some wifi chips in tethering 
smartphones also have a specified limit.

Alex

> 
> Fred
> 
> 
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