LAN file sharing and internet browsing

LAN file sharing and internet browsing-Linux Enterprise Application-Linux server application information. For more information, see the following. Prawns:
Younger brother just transferred fedora5, with KDE3.5.1-2.3 Red hat version, want to be a file server.
Specifically, there is a Windows XP Machine sharing the adsl connection in the network. The local machine uses its Internet connection to access the Internet and share folders in the local machine.
In network configuration setup-the network address in the Ethernet device is set to automatically obtain the IP address. When dhcp is used, the Internet can be accessed, but the sharing created with samba cannot be used, and other machines cannot find the local machine; you cannot access the Internet when using a fixed IP address. However, by searching for the address of the local machine on the winxp machine's network, you can find the shared folder and use it properly. Can someone help you with the analysis? Thank you!
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