Re: [6tisch] Extending CoJP (minimal-security) for non-6TiSCH 802.15.4 networks

Christian Amsüss <> Mon, 20 September 2021 09:13 UTC

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Date: Mon, 20 Sep 2021 11:13:11 +0200
From: Christian =?iso-8859-1?Q?Ams=FCss?= <>
To: Michael Richardson <>
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Subject: Re: [6tisch] Extending CoJP (minimal-security) for non-6TiSCH 802.15.4 networks
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Hello Michael,

On Sun, Sep 19, 2021 at 03:48:44PM -0400, Michael Richardson wrote:
> > have the discussions in the development of CoJP ever sidetracked to its
> > applicability for non-TSCH setups?
> not really.

thanks, that's good to know too.

> I think that the CoJP worked very very hard to keep it at one round trip.
> This is due to congestion concerns further up the RPL tree.
> I don't perceive that these other technologies have this problem to the same
> degree.

Running 6LoWPAN in other modes could still be RPL-based. The nodes close
to the BR would still see much traffic, though they might deal with it
differently than 6TiSCH. (Especially with the simpler modes, I expect
congestion to even have worse effects than with 6TiSCH).

Anyhow, there don't appear to be any parts that are particularly hard to
implement that could be dropped with a less strict one-roundtrip rule,
so overall it's still a good property.

I'll explore this further as time permits, and hope to at some point
come back asking for opinions on a concrete proposal.


To use raw power is to make yourself infinitely vulnerable to greater powers.
  -- Bene Gesserit axiom