reliably detecting the presence of a bridge?

Jared Mauch jared at
Tue Dec 15 13:04:36 UTC 2015

On Tue, Dec 15, 2015 at 10:48:50AM +0100, Dave Taht wrote:
> I am curious if there is some sort of igmp or other form of message
> that would reliably detect if a switch had a bridge on it. How could
> deviceA detect deviceC was a bridge in this case?
> deviceA  -> ethernet switch -> deviceB
>                     ethernet switch -> deviceC with bridged wifi and ethernet
> question came up in the context of:

	The best way I've seen is to measure latency to the devices and infer from there.
You can always make the latency longer, but making it shorter is much harder :)

	- Jared

Jared Mauch  | pgp key available via finger from jared at
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