What happens if two computers have the same IP address?

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We've just encountered this problem - but when you have a large site and a lot of PCs how do you find the rogue machine? It seems intermittent (may be a portable PC or even a PDA) so don't have much time to track it down... suggestions more than welcome!!

Ian (UK)

Hi, I have a router with two computers, a laptop, and two xboxes hooked up together. 1 computer and a laptop are on wifi, and the rest are hard wired. when i have both of the xboxes on at the same time, i get the same ip address on both of them. when i try to change them using static ip, they don't connect to the internet. i need help because this is very frustrating. thanks.

Hi, i have a wireless router for 2 pc. Each PC has own ip address. But when i create eMule in Virtual Server List, only 1 ip address allow to key the eMule port (TCP and UDP). What should i do?
Thanks

hi, my mate and i want to play together on the same poker tables except when we try and sit down on the same table, we get the same message, ''you cannot sit down at this table because somebosy is already sat down with the same ip address as you'' now, we live 3 miles apart, so how do we get around this strange problem, any ideas welcome, thanks

CAN TWO DIFFERENT COMPUTERS HAVE THE SAME IP ADDRESS.I HAVE RECIEVED HARASSING EMAILS AND THE IP ADDRESS FOR THESE MATCH MY FRIENDS IP ADDRESS. COULD THESE OR ARE THESE COMING FROM HER COMPUTER? I THINK THEY ARE!

Hey!
I'm sitting on a very special modem (special in my country). It uses satellite power to download, but regular 56k-technology to upload.

Don't know if this makes any difference, but every other time i try to download something from rapidshare it says that im already downloading something from rapidshare-servers..

The problem here is...IM NOT DOWNLOADING ANYTHING!

There is only one computer in my house and it is mine, so why is it that someone can use my IP while I'm using it?

Hi, I have two computers running from the same broadband modem. One is connected wireless the other by a cable connection. Both machines connect fine together to the net. Their is NO NETWORKING connection between the two pc's.
My question is - is it possible for someone to use either pc out of the two and be able to track or 'see' where the other computer user has been???

Also is it possible for the master pc user to 'see' or 'divert' email going to the 2nd pc?
Both pc's use the same log on name and password as they both have to connect to the same network but both the pcs work independently of each other with seperate email accounts - basically from this scenario is it possible for one user to hack or see what the other is doing via the other computer? And if so how far regarding this can they go?

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1) I'm not sure what you mean by "no networking connection" between the
two. Obviously they are joinced to the same broadband modem, and that,
therefore provides some type of physical networking connection between
them. *Depending on the modem* it may be possible for either computer to
see or "sniff" the network traffic happening on the other. This is the
case if the modem acts as a simple hub. More commonly it does not,
acting more like a router, in which case they should not see each
other's traffic.

Unfortunately it's not really all that easy to tell or confirm exactly
hwo your modem is operating.

2) It's just as possible as with any computer elsewhere on the internet.
Accounts do get hacked, but I don't see anything here that makes it more
likely because of your network setup, UNLESS the traffic can be sniffed,
which depends on the answer to your first question. If the traffic can
be sniffed, then absolutely the account could quite easily be hacked.

Leo
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Referring back to the 2 computers 1 ip address.
I would like to elaborate on this.

Two computers and one modem.
Both computers connect to the same router modem.
Both computers are usually connected at the same time. Can this situation be regarded, treated like or become a network situation like you would find in an office environment?

Unlike an office both computers run independently from each other and only use the same router for internet access.
Is it possible for one computer to 'spy' on the other computer when both are connected to the net?
as if in a networking scenario?.

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It depends entirely on the functionality provided by that modem. If it's
acting like a full NAT router (which it might be), then I'd expect that
to be very similar to a standard home network.

Leo
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