This article discusses the relationship and differences between the Universal Plug and Play (UPnP) and the Internet Gateway Device Discovery and Control Client capabilities of Windows XP. Internet Gateway Device Discovery and Control Client and UPnP each provide distinct, but complementary, features that permit users to easily control network devices.
UPnP is a collection of standards and protocols that permits Windows to provide discovery and interoperability between a wide variety of Universal Plug and Play network devices. When connected to a network, UPnP devices immediately provide their services and use other services on the network. For example, when you plug in a Personal Digital Assistant (PDA) or a laptop, you are immediately able to use devices such as printers and other resources on the network. Such devices may include anything from standard computing equipment to kitchen appliances and home entertainment systems. UPnP does not determine the APIs that programs must use, but permits the operating system developers to create the APIs that customers need. By default, the UPnP client is not installed.
Note UPnP has very little in common with Plug and Play or non-Plug and Play devices.
The Internet Gateway Device Discovery and Control Client permits Windows to detect and interact with Internet gateway devices (IGDs). IGDs include routers and computers running Internet Connection Sharing. Such devices can support detection by either UPnP or the Internet Gateway Device Discovery and Control Client. IDG devices use the Simple Service Discovery Protocol (SSDP) to broadcast their availability on the network. This permits clients to automatically locate the IDG device and use the device as their default gateway for external network access. By default, the Internet Gateway Device Discovery and Control Client is installed.
Note SSDP defines how network services can be announced and detected on the network.
Connection Sharing computers and most wireless devices use SSDP and Internet Gateway Device Discovery. However, only some of these devices are also UPnP devices. Those that are UPnP devices permit additional control functions.
The combination of Internet Gateway Device Discovery and Control Client and UPnP permits you to both monitor and manage your shared Internet Gateway from a client computer. The Internet Gateway Device Discovery and Control Client automatically detects that there is an IGD device because of the SSDP broadcast, and then provides clients with information about the internet connection. Depending on the security setup, clients may also be able to control the connection. The Internet Gateway Device Discovery and Control Client does not supply information about the rights of the clients. When a computer that runs Connection Sharing when SSDP broadcasts are present detects the broadcast, an icon for the Connection Sharing host computer automatically appears in the Network Connections folder on the client computers. This icon permits Connection Sharing clients to remotely monitor and control the shared Internet connection.
By default, the Internet Gateway Device Discovery and Control Client is installed, whereas UPnP is not. In this default configuration, an Internet Connection icon appears in the Network Connections folder, and a Broadband Router icon does not appear in the My Network Places folder.
If you want a Broadband Router icon to appear in the My Network Places folder, you must install UPnP. To install UPnP, follow these steps:
Click Start and then click Control Panel.
In Control Panel, double-click Add or Remove Programs.
Click Add/Remove Windows Components.
In the Components list, click Networking Services, and then click Details.
Select the Universal Plug and Play check box, and then click OK.
Click Next, and then click Finish.
For additional information about Universal Plug and Play, click the following article number to view the article in the Microsoft Knowledge Base:
323713 Description of Universal Plug and Play Features in Windows XP
300546 Overview of Remote Assistance in Windows XP