How to know third party's IP.

There's no way for you to know the IP address. It's different every time that machine logs onto the ISP. Since the machine won't be registered with any DNS servers there is no way to resolve the IP address. Not even RARP will work because there has to be a RARP server in place to receive the MAC address broadcast from the host machine.

There is no way for you to find the IP address of another computer from your computer.

The method used by gamers to let each other know their IP addresses is to find their own IP address using winipcfg or similar and then use MSN Messenger or ICQ or other chat client to let each other know what the IP address is.

It is possible to do this using RARP, but you will need to install RARP-server on the machine, connected to ISP. Moreover - you'll need some kind of utility that will change RARP-server configaration. And you'll need to use RARP-client on other PC.
There is other way - if you both have connection to Internet - you can get IP address using Dynamic DNS service.
www.dtdns.net or www.dotster.com or www.dyndns.org etc.

And third - if you both are in same network and have file sharing: you canhave some utility to place a file with IP on disk and second PC will read it. Sometimes people use this on web too - they publish IP address on site for other people.
It is possible to use custom client and server, if your first PC knows IP addressof second PC. It will notify second PC itself, but this is custom software. It can even modify "hosts" file on second PC, so it will know address immidiately.

Sincerely, Sergey
Brainbench MVP for Win98 Administration

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