Re: [ietf-smtp] Endless debate on IP literals

"John Levine" <johnl@taugh.com> Wed, 01 January 2020 20:02 UTC

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Date: Wed, 01 Jan 2020 15:02:39 -0500
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From: John Levine <johnl@taugh.com>
To: ietf-smtp@ietf.org
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Subject: Re: [ietf-smtp] Endless debate on IP literals
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In article <20200101193816.GP73491@straasha.imrryr.org> you write:
>> More broadly there's a widespread misconception that isolated networks
>> are not subject to security threats or that perimeter defenses are
>> sufficient to protect them, even when such networks are used to manage
>> critical infrastructure or equipment that can create hazards if not
>> properly managed.
>
>It is not always a misconception, rather it can be a realistic
>assessment that the cost of managing authentication may not be worth the
>effort, and the barriers to get it working on specialized appliances are
>quite high.

More than that, more complex authentication doesn't solve the problem,
since compromised devices can send authenticated spam.

If you're concerned about threats to and from IoT devices,
isn't that more what MUD addresses?