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From: Marek Lindner <lindner_marek@yahoo.de>
Date: Sat, 26 Mar 2011 16:31:42 +0100
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Subject: Re: [B.A.T.M.A.N.] TTL yes, TTL no
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Hi,

> In these days I was wondering whether the TTL field in the OGM packet is
> really useful or not...Due to hop_penalty an OGM will be discarded as
> soon as the TQ will reach 0 (which is a sort of TTL mechanism itself).
> At this point why is the TTL field needed?

uhm.., you probably are right. As long as there is a hop penalty it also 
functions as a TTL. Keep in mind that it is possible to set the hop penalty to 
zero. With the current default hop penalty of 10 the maximum number of hops is 
limited to 25.


> Someone could probably say that a node far at least TTL hops will never
> be reached by a unicast packet, then it is meaningless to let it know
> about me. But then it could be possible to recalibrate the TTL such that
> it has to be equal to the maximum length in number of hops of the longest
> path the OGM can traverse.

Not quite sure what you are proposing. A TTL of TQ_MAX / hop penalty ?

Cheers,
Marek