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Re: [ietf-smtp] Characteristics of Isolated (or mostly-isolated) industrial IP Networks

Dave Crocker <dhc@dcrocker.net> Mon, 06 January 2020 14:28 UTC

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To: John Levine <johnl@taugh.com>, ietf-smtp@ietf.org
References: <20200105171930.0054211FC46D@ary.qy>
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From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Mon, 06 Jan 2020 06:28:11 -0800
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Subject: Re: [ietf-smtp] Characteristics of Isolated (or mostly-isolated) industrial IP Networks
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On 1/5/2020 9:19 AM, John Levine wrote:
> In article <3c50a793-dd26-3254-f9e3-b642793918b7@dcrocker.net> you write:
>> What else is distinctive?
...
> If it sent mail to any other address, or if the message rate was much above
> one a minute, we'd know something was screwed up with its mail.


This sounds like a variant of blocking outbound port 25.


d/
-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net

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