Originally Posted by Oubadah
Can someone explain to a pitiful network noob what UPnP does (in a nutshell) and whether disabling it will interfere with my networking:
- Windows 7/XP PCs sharing using passwords and user accounts (homegroup disabled) and participating in LAN games.
- Dedicated game server running for LAN + internet clients.
- Blu Ray player, xbox and TVs accessing DLNA server on one of the PCs
- Blu Ray player accessing shared folders on various PCs (CIFS)
- Xboxes connecting to xbox live
do any of those activities need UPnP?
I think UPnP was disabled by default in PFSense, but I enabled it a while ago to try and solve issues with windows PCs randomly not being able to see other ones (in Explorer) and sometimes not even being able to connect via \\COMPUTERNAME. However, I don't think it actually made any difference to that, so I'm wondering if I should re-disable it.
UPnP is a collection protocols that allows device to seamlessly discover each other on a network and establish services for various tasks such as communication, entertainment, or sharing of files. UPnP is not for the enterprise.
Conceptually, UPnP is an extension to "plug and play" (i.e. Windows plug and play), in the sense you can connect network devices and they just work with each other (hence universal), however it is not related to "plug and play", nor does it depend or physically extend it.
UPnP consists of:
Addressing - The device either assigns itself an address or talks to a DHCP server (i.e. an IP address for the device must be obtained automatically without the need for configuration).
Discovery - Once an address has been established for a UPnP device, the device uses SSDP (simple service discovery protocol). This allows the device to advertise its services to the rest of the network.
Description - An XML file that contains information about the type of UPnP device and other information.
Control - Device-type specific services that enable the UPnP device's services to be communicated with (for example, a router implementing UPnP may expose a port forwarding control point).
Event notification - Also called "eventing", this is implemented by UPnP devices to notify others that a value pertaining to a UPnP service has changed - other devices subscribe to events that they want to receive updated information for.
Presentation - Basically can allow the user to control the device or view status information about it via a web page, if the UPnP device exposes one.
One specific thing we were talking about here is called NAT traversal which is actually called IGD (Internet Gateway Device Protocol). This is implemented by residential UPnP gateway devices (such as home routers). Control points might consist of getting an external (WAN) IP address, or add/remove port mappings - for example a game may communicate with an IGD control point to traverse the NAT firewall on a gateway so that it can be accessed from the Internet. This requires knowledge of what NAT is and how it works.
Disabling UPnP on your gateway/router should not interfere with any of the services you listed. My DLNA networking still works without UPnP on the gateway.
Originally Posted by Plan9
Why not read Wikipedia? That's what the site is there for and there's little anyone on here can post that isn't already explained pretty will in the wiki: https://en.wikipedia.org/wiki/Universal_Plug_and_Play
In answer to your specific set up, DLNA uses UPnP for discovery. So if you're want to use DLNA streaming then you'll need UPnP enabled.
The Windows discovery issue is to do with NetBIOS or WINS or something. It's not UPnP, it will be some crappy proprietary solution Microsoft have kludged together.
Windows file sharing talks over TCP/IP - there's no NetBIOS or WINS anymore, unless a legacy device requires NetBIOS over TCP/IP. Windows does use SSDP for discovery in Windows Vista and later.
For the record Microsoft do not "kludge" things together.