Summary

Here’s what you know about Web sharing, FTP access, and remote login after reading this Chapter:

• Every computer on a network or the Internet has an IP address. With Mac OS X, a computer can have a different IP address for Ethernet, modem, AirPort, and other network ports.

• If you have a public IP address, then computers on the Internet can use your computer’s network services. If you have a private IP address, then Internet computers must go through a gateway on your network to use your computer’s network services.

• A dynamic IP address may change each time you begin an Internet session or each time your computer starts up. A static IP address doesn’t change.

• You can get your computer a name, which a name server on your network or the Internet looks up to get your IP address.

• You can host a Web site by turning on Web sharing in the Sharing preference pane. Your Web site files go in the Sites folder inside your home folder. Files for a joint Web site shared by all users of your computer go in the Documents folder of the WebServer folder in the main Library folder (path /Library/WebServer/Documents/).

• The URL for your personal Web site has the form http://192.168.0.1/~user/ or http://mycomputer.mydomain.com/~user/. The URL for your computer’s joint Web site has the form http://192.168.0.1 or http://mycomputer.mydomain.com. (Substitute your computer’s address or name and the short name of your user account.)

• If you turn on the FTP access option in the Sharing preference pane, other computer users can transfer files to and from your computer. Binary files must be encoded before FTP transfers them. FTP does not protect user account names, passwords, or file transfers from network attackers.

• Mac OS X does not normally allow anonymous FTP access, but you can enable it.

• For FTP access to your computer, other computer users specify your computer’s IP address or name and their user account name and password.

• SFTP is secure FTP and is superior to FTP in terms of security. If the remote host supports SFTP then you should use an SFTP client if possible.

• Turning on the Remote Login option in the Sharing preference pane enables other computer users to securely log in to your computer, copy files, and send Unix commands.

• For remote login, other computer users specify your computer’s IP address or name and their user account name and password.