Re: [Trans] Gossiping in CT

Ben Laurie <> Mon, 29 September 2014 13:19 UTC

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Date: Mon, 29 Sep 2014 14:19:48 +0100
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From: Ben Laurie <>
To: Gervase Markham <>
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Cc: "" <>, Linus Nordberg <>
Subject: Re: [Trans] Gossiping in CT
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On 29 September 2014 14:03, Gervase Markham <> wrote:
> On 27/09/14 14:36, Linus Nordberg wrote:
>> This gossiping that people is talking about, what is it? Here's a
>> summary of what I think some people mean when they say gossip and what
>> problem this thing tries to solve. It's based on a few IETF-related
>> documents and not the full picture. I'd be interested to hear what other
>> people read into the concept of gossiping in CT
> It seems that your summary might have one misapprehension. As I
> understand it, gossiping is not something that clients (in the web
> browser sense) do. After all, one point of CT is to avoid extra network
> requests at connection time. Gossiping is a log-to-log concept, where a
> group of logs can determine that a particular log is rogue because of
> what they hear about what it's saying, and any inconsistencies in that.

We imagine _all_ participants in the protocol gossiping. Yes,
gossiping STHs in the current plan does introduce a small amount of
extra overhead into the connection, but it really is small.