Re: rfc4941bis: On the use of multiple addresses

Fernando Gont <fgont@si6networks.com> Thu, 30 January 2020 23:35 UTC

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Subject: Re: rfc4941bis: On the use of multiple addresses
To: David Farmer <farmer@umn.edu>
Cc: "6man@ietf.org" <6man@ietf.org>
References: <4c7c16fd-ddef-eec0-d34e-29e91df6ce25@si6networks.com> <CAN-Dau0h-XtzgG9ex0mvqYejX_LOd+oKvBXx5065kaD5W_1mWA@mail.gmail.com>
From: Fernando Gont <fgont@si6networks.com>
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Date: Thu, 30 Jan 2020 20:34:41 -0300
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On 30/1/20 20:20, David Farmer wrote:
> 
> 
> On Thu, Jan 30, 2020 at 4:54 PM Fernando Gont <fgont@si6networks.com 
> <mailto:fgont@si6networks.com>> wrote:
> 
>     Folks,
> 
>     Based on the recent discussion regarding the possible impact of the use
>     of multiple addresses, I suggest we include the following text in
>     Section 4 of rfc4941bis:
> 
>     "Network deployments are currently recommended to provide multiple IPv6
>     addresses from each prefix to general-purpose hosts. However, in some
>     scenarios, use of a large number of IPv6 addresses may have negative
>     implications on some network devices (e.g. [RFC6583]), exacerbate other
>     operational problems (e.g. [draft-ietf-mboned-ieee802-mcast-problems])
>     and/or may lead to traffic employing these addresses being dropped by
>     devices that enforcing port security that may enforce a limit on the
>     maximum number of configured addresses per host (e.g. [RFC7039]). A
>     discussion on possible approaches to allow for unconstrained use of
>     IPv6
>     addresses can be found in [RFC7934]"
> 
> 
> maybe "...found in [RFC7934] and one of theseĀ approaches is defined in 
> [RFC8273]."

Certainly [RFC8273] sketches how to do "Unique Prefix Per Host with 
SLAAC". However, I wonder the state to which it is a spec: there are 
many things that are unspecified. Besides, in all fairness, one should 
also mention DHCPv6-PD. Not sure if I would go for that level of detail...

THoughts?

-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492