Re: [manet] [Technical Errata Reported] RFC7466 (7477)

[Henning Rogge <[e-mail]>]

On Mon, May 1, 2023 at 2:55 PM Christopher Dearlove
<[e-mail]> wrote:
>
> If you know that the kink is cut off you would use the link quality mechanism to stop that link being considered symmetric, and thus would stop reporting it in TC messages (among other changes). Using link quality as a binary good/bad state is a perfectly reasonable approach.

But a little bit harsh for a link that might just have missed one/two
Hellos... it might be the only link between two parts of the network.

> You can’t adjust the link metric value in TC messages, because (a) you don’t know what it should be, and (b) you will create inconsistencies that could lead to looping. Just stopping reporting (updating sequence number) is the best you can do. And using link quality does that.

I can adjust the content of the TC my local router is producing... at
the moment I am experimenting with a mechanism that will (as soon as a
link is overdue based on Hello-Interval) use a similar "penalty" to
the outgoing link metric in the local database than the metric
algorithm (slightly modified DAT at the moment) does on the incoming
one based on the time interval... which means this penalty will be
instantly gone a new PacketBB packet arrives from the neighbor.

It works quite well if both ends of the link run the same metric algorithm.

Henning