Re: Help?

From: Dave Pimlott (newsgroups@SPAMFILTERdavepimlott.info)
Date: 05/24/02 

Date: Fri, 24 May 2002 16:21:49 +0000
From: Dave Pimlott <newsgroups@SPAMFILTERdavepimlott.info>

NeO wrote:
> E-mail does not go directly to the address your sending it to, right?
> It can travel through many computers to get to its destenation, right?
> So, ive got a regular (actually crappy) isp....dial-up connection, are
> you saying i wouldnt be able to read any email that is going from
> computer to computer? I'm kinda confused, if its not to much trouble,
> can you please explain this much better? Thanx

try this dodgy ascii art:

userA@domain1->some_intermediate_computer->userB@domain2
                  ^
                  |
               Dial_up_user

for sake of keeping things simple the path from domain1 to domain2
requires only one intermediate machine.

for Dial_up_user to read the mail (or any other traffic) going from
domain1 to domain2 you will need two things:
- be able to log onto the intermediate machine
- have access to packet sniffing software [1]

OR

- have someone start the packet sniffer for you
- be able to copy sniffed packets to somewhere else (e.g. dial_up_user)

You *will* be able to sniff traffic going to or from *your* machine to
anywhere else.

I think if you read a tutorial about how TCP/IP works then you will
understand a lot better about what packet sniffing is, and how it works.

[1] Packet sniffer - generic term for any software that puts one or more
network interfaces into "promiscuous mode" [2] and parses the raw data
on the (network) wire(s) into something that can be displayed on a
screen.
[2] promiscuous mode - in this context, a network interface that passes
all packets seen on the network to the operating system regardless of
the intended destination, contrast this to the normal mode of operation
where the network interface (or the interface software) discards packets
that are not being sent to it.

If this still doesn't help, then I am afraid you will have to RTFM.

Dave Pimlott

Relevant Pages

  • Re: Help?
    ... for sake of keeping things simple the path from domain1 to domain2 ... - have someone start the packet sniffer for you ... network interfaces into "promiscuous mode" and parses the raw data ... where the network interface discards packets ...
    (comp.security.misc)
  • ethX interface rx errors
    ... Spontaneous system crash with heavy generic load or high packet traffic. ... SIOCGMIIPHY on 'eth1' failed: Operation not supported ... Basic mode control register 0x3000: ... device eth0 entered promiscuous mode ...
    (Linux-Kernel)
  • Re: Packet Sniffer
    ... Netlog does not put an adapter into promiscuous mode. ... normally set the packet filter to promiscuous. ... I think that you would need to write your own NDIS protocol driver to ...
    (microsoft.public.pocketpc.developer.networking)
  • Network problem with TCP packets
    ... Network Interface. ... I'm developing an application that sends packet at 5Hz over a TCP ... then the 256, and so on until there are no more free clusters, and the ... socket closes itself. ...
    (comp.os.vxworks)
  • Re: Promiscuous Mode
    ... of an incoming packet to its own and passes it onto the operating system ... Otherwise, the packet is dropped. ... However, when put into promiscuous mode of operation, the NIC stops this ... comparison and just grabs ALL the incoming packets and passes them to ...
    (Pen-Test)