Flip a bit in the Ethernet FCS as it egresses deviceA. If the frame
arrives with a correct checksum at deviceB, then there's a switch in the
middle. Most modern switches recalculate FCS at egress port.
If the frame never arrives, most likely there is a switch in between. If
the frame arrives with the broken FCS, there is no intermediate switch.
--Andrew
On 12/15/15 4:48 AM, 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:
http://lists.alioth.debian.org/pipermail/babel-users/2015-December/002231.html
--
Dave Täht
Let's go make home routers and wifi faster! With better software!
https://www.gofundme.com/savewifi
