Originally, "port" referred to the connectors on the back of the computer: printer port, serial port, joystick port, and so on. Like a seaport, a computer port is somewhere for a device to "dock" or connect to the computer.
Connections made on a network also happen via ports, although in this case there's no physical connector. Internet ports are virtual connections, but the idea is the same. For example, when you access a website you make a connection to the site's Web server over port 80. There's no physical port 80, it's just a way of separating traffic coming in over the network.
UDP stands for User Datagram Protocol, a protocol used by streaming audio and video.
Agreements within the Internet community determine what port a particular service uses. Ports 0 through 1,024 are reserved by IANA, the Internet Assigned Numbers Authority. Other applications claim ports from 1,024 to 65,536. For example, iTunes uses port 3,689 for its music sharing.
Windows XP Security | Windows Wi-Fi Flaw Lets Others See Your Stuff | January 17, 2006
When Windows powers up but doesn't find a wireless access point, it creates an ad hoc network, complete with the SSID, the Wi-Fi network identifier, like "linkysys" or "actiontec," of the last network connection
Recommended that users disable wireless when it's not used, or set Windows' wireless to connect only to access points, not individual notebooks - (click on the wireless icon in the System tray, and open the Wireless Network Connection Properties window. Click on the Wireless Network tab, click on the Advanced button, and click on "Access point (infrastructure) networks only.")
An even easier way to block the "feature" is to use any firewall, even Windows XP's default firewall
If you don't want others to access your files, you can prevent other users from accessing your folders and the files they contain. When your computer is connected to a domain, this is called setting permissions for your file or folder. When your computer is connected to a workgroup, this is called making your folders private.
A Homegroup makes it easy to share pictures, music, documents, videos, and printers with other Windows 7, Windows 8, Windows 8.1, and Windows 10 computers on your local home network. You can also stream media to devices. When a PC creates a homegroup, the homegroup is protected with a password. To join a homegroup, you will need the homegroup password, which you can get from the PC that created the homegroup or any PC already joined to the homegroup.
Starting with Windows 10 build 17063, the HomeGroup service is no longer operational in Windows 10. The user profile used for sharing and the file/folder/printer shares will continue to work.
Easier Connection: No more remembering cryptic HomeGroup passwords in order to connect to another PC. You can now simply connect through your Microsoft Account email address across devices.
To rename the Homegroup, go to CONTROL PANEL > SYSTEM > Advanced system settings > COMPUTER NAME > Change. All the PCs on your network that have this name will be able to see each other.
However, I find that Windows has this annoying habit of trying to change the workgroup's name back to its Windows default (Workgroup or MSHome) every time there is a Windows Update.
What is the difference: a domain, a workgroup, a homegroup?
Sharing
For those who prefer not to use the Cloud (OneDrive) to connect their devices, the Share functionality for folders and printers allows you to see the available devices and connect them to and from other PCs on your home network.
Network discovery -|- If you open File Explorer, go to Network, and see an error message ("Network discovery is turned off…."), you'll need to turn on Network discovery to see devices on the network that are sharing files. To turn it on, select the Network discovery is turned off banner, then select Turn on network discovery and file sharing.
\\localhost -|- How do I tell which files or folders I've shared over a network? Open File Explorer (= Windows Explorer, not Internet Explorer), then type \\localhost into the address bar. Note: When you've shared a file from a folder in your user profile and you go to \\localhost, you'll see your user profile and all its files there. This doesn't mean that all of your files are shared—just that you have access to all your own files.
Networking is built in to Windows 98. Just install the internet connection sharing feature through add/remove software/windows setup. Internet Connection Sharing comes free in Windows 98. You can hookup a hub to a second NIC in your sharing system and plug in as many PC's as you can afford.
Hide shares from browsing by adding $ to the end of the share name.
Remove the Everyone group from sharing and from NTFS permissions.
Hide your server in order to prevent users from accessing the server through the browse list.
NET CONFIG SERVER /HIDDEN:YES
UNC path can still access the server.
IP address can still access the server.