Re: Informed regulator about the shorter-than-64 necessity on 3G/4G/5G

Fernando Gont <> Tue, 19 January 2021 00:02 UTC

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Subject: Re: Informed regulator about the shorter-than-64 necessity on 3G/4G/5G
To: Alexandre Petrescu <>, IPv6 <>
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From: Fernando Gont <>
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Date: Mon, 18 Jan 2021 19:04:12 -0300
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Hi, Alex,

On 18/1/21 05:45, Alexandre Petrescu wrote:
> Hi, 6MANners,
> Today I formulated a brief personal email to some person(s) at the
> regulator agency suggesting the allocation of shorter-than-64 prefixes
> (e.g. /56) to end users.
> I explained that the current situation where each of the mobile
> operators deliver a /64 and not shorter to smartphones is not usable for
> networks such as mobile hotspots or in-car multi-subnet networks.
> I informed that there are some I-D proposals of Variable SLAAC that is
> relatively refused at IETF because of the IETF necessity of 64bit (and
> not shorter) IIDs.

This seems to be confusing things.

Proposals for "classless IPv6" (e.g.: 
draft-bourbaki-6man-classless-ipv6) are meant to allow SLAAC to work 
with *longer* prefixes (i.e., shorter IIDs)

Shorter prefixes (i.e., bigger address blocks leased to users) are 
already supported by DHCPv6-PD, without the need of any additional 
protocol action.

Fernando Gont
SI6 Networks
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492