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Re: bridge detection
From: Aaron Berg <aaron () voyageurweb com>
Date: Tue, 28 Dec 2004 12:41:30 -0600

One way of detecting a router, switch, bridge etc is to count the ttl from one location to another and compare it to the number of hops you see. For instance say your going from a main router to an ISP main router. There may be many different devices in between. Do a ping and set the time to live to 1. If the ping makes it there and back then you know there is nothing in between. If not set the ttl to 2, 3, 4 etc until you get a return ping. There are a few applications out there that will do this for you. Look for tcp based ping utilities such as TCPping. If any of the information I have provided is slightly off feel free to correct me.

G.P.M wrote:

  I was wondering are there any programs which can detect switches/routers, based as well on linux.
  The problem is that one company is setting up large LAN, with internet access, based on static ip/mac address, for 
paying reasons. Many clients seperate their connection, often giving mac of the bridge not the PC.
  i had many ideas about that, eg. checking the vendor for the mac, signal replays from the source.
i worry also about 'clear' switches, non programmable ones.

 Could please someone give me some advise?

sorry for my bad english.

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Aaron Berg
VoyageurWeb Engineering

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