Re: [Webpush] Spencer Dawkins' Yes on draft-ietf-webpush-encryption-08: (with COMMENT)

Martin Thomson <> Wed, 16 August 2017 00:04 UTC

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From: Martin Thomson <>
Date: Wed, 16 Aug 2017 10:03:50 +1000
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To: Spencer Dawkins <>
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Subject: Re: [Webpush] Spencer Dawkins' Yes on draft-ietf-webpush-encryption-08: (with COMMENT)
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On 16 August 2017 at 02:15, Spencer Dawkins
<> wrote:
> I found “for efficiency reasons” in this text
>   For efficiency reasons, multiple users of Web Push often share a
>    central agent that aggregates push functionality.
> To be so broad that I wasn’t sure what you were telling the reader. Are there
> any specific efficiencies that you could call out, so that we’d better
> understand why central agents are used? And if that’s already written down
> someplace, adding a pointer would be even better.

It's engineering efficiency more than anything else.  On mobile
platforms, this is the platform; on browsers, the browser.  If I
remove the "for efficiency reasons" clause, I don't think we lose

> I’m curious about algorithm agility, but I’m not the person to ask that
> question ...

It's a common question.  Common enough that I'll add some text and
avoid future occurrences.

We have deployment experience with this already.  We deployed an
earlier version, then had to change it a few times.  So we know how to
do this.  The User Agent tells the application what content codings it
likes.  The W3C spec has a supportedContentEncodings parameter on the
PushManager interface that does this

For you: