Re: [v6ops] [EXTERNAL] Re: Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)

Ted Lemon <> Tue, 16 February 2021 18:32 UTC

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From: Ted Lemon <>
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Subject: Re: [v6ops] [EXTERNAL] Re: Scope of Unique Local IPv6 Unicast Addresses (Fwd: New Version Notification for draft-gont-6man-ipv6-ula-scope-00.txt)
Date: Tue, 16 Feb 2021 13:32:31 -0500
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Cc: IPv6 Operations <>, "" <>
To: Philip Homburg <>
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On Feb 16, 2021, at 1:28 PM, Philip Homburg <> wrote:
>> The true greatness of dual-prefix multihoming, in my opinion, is
>> "hosts get to decide which ISP to use", so a given host can decide
>> "I want to use ISP A for my web traffic, and ISP B for my voice traffic"
>> (by picking the corresponding source address).
> We see that hosts don't even implement the basics, so this seems
> to be a bit of a pipe dream,

Indeed, I have no idea how a host would know.

It might be nice to be able to somehow configure the network to treat one link as preferred over another, e.g. if one connection is expensive. Of course, since the user isn’t likely to know to configure that, it needs to be automatic, and I don’t think an automatic mechanism has been specified.