guessing values for an unknonwn network ?

Is there a tool that is able to guess gateway, dns, netmask and ip
address just by passively analyzing the network traffic ?

In some case it can be handy just to plug and go...

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++ "All great truths begin as blasphemies." -George Bernard Shaw
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Pietro wrote:

> Is there a tool that is able to guess gateway, dns, netmask and
> ip address just by passively analyzing the network traffic ?
>
> In some case it can be handy just to plug and go...

There's something even better: Let your system make the "network"
give it the parameters.

man DHCP.

Wolfgang Draxinger
--

On 2006-07-12, Wolfgang Draxinger <(E-Mail Removed)> wrote:
>> Is there a tool that is able to guess gateway, dns, netmask and
>> ip address just by passively analyzing the network traffic ?
>> In some case it can be handy just to plug and go...
> There's something even better: Let your system make the "network"
> give it the parameters.
> man DHCP.

The point of "guessing" is to plug your pc in an unknown network, with
no dhcp, or just a closed dhcp server (that requires your mac address to
match to give you an ip address) and get a random ip address that is not
used at the moment. I'm sure that, even in a switched netowrk, it would
be possible to make an educate guess about ip and gateway, just by
sniffing packets passing by. The first step would be to bring up you
interface with address 0.0.0.0, then passively sniffing traffic for a
while and guessing something. It certainly not a fool proof method, but
it can work in certain environment... An it matter of writing a number
of heuristics...

Do you know of any tools of this kind ?


p

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++ "All great truths begin as blasphemies." -George Bernard Shaw
++ Please avoid sending me Word or PowerPoint attachments.
See http://www.fsf.org/philosophy/no-word-attachments.html

On Wed, 12 Jul 2006, in the Usenet newsgroup comp.os.linux.networking, in
article <v6meo3-(E-Mail Removed)>, Wolfgang Draxinger wrote:

>Pietro wrote:
>
>> Is there a tool that is able to guess gateway, dns, netmask and
>> ip address just by passively analyzing the network traffic ?

Sure - it's called tcpdump (and some experience)

>> In some case it can be handy just to plug and go...

Then too, you can simply ask the network administrator.

>There's something even better: Let your system make the "network"
>give it the parameters.
>
>man DHCP.

You're making the assumption that there is a DHCP or BOOTP server on the
local network segment, or a boot-forwarder agent on a router. I've never
worked on a network that had either.

Old guy