reliably detecting the presence of a bridge?

William Herrin bill at
Tue Dec 15 15:19:37 UTC 2015

On Tue, Dec 15, 2015 at 4:48 AM, Dave Taht <dave.taht at> 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?

Hi Dave,

Start with precision in language. An ethernet switch is one form of
ethernet bridge although the reverse is not necessarily true. So, a
switch is always a bridge by definition. Q.E.D.

>From what you've posted, you don't want to detect the difference
between a switch and a bridge, you want to detect the difference
between a wired and wireless segment segment in the network. Is that
correct? Any wireless link or just radio? Any radio link or just
802.11 wifi? Are you just trying to detect stations behind wireless or
do you want to identify segments that are carried over wireless?

Bill Herrin

William Herrin ................ herrin at  bill at
Owner, Dirtside Systems ......... Web: <>

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