Universal Plug and Play(UPnP)
The UPnP architecture allows peer-to-peer networking of PCs, networked appliances, and wireless devices. It is a distributed, open architecture based on established standards such as TCP/IP, UDP, HTTP and XML.
The UPnP architecture supports zero-configuration networking. A UPnP compatible device from any vendor can dynamically join a network, obtain an IP address, announce its name, convey its capabilities upon request, and learn about the presence and capabilities of other devices. DHCP and DNS servers are optional and are only used if they are available on the network. Devices can leave the network automatically without leaving any unwanted state information behind.
Other UPnP features include:
- Media and device independence
- UPnP technology can run on many media that support IP including Ethernet, FireWire, IR (IrDA), power lines (PLC) and RF (Bluetooth, Wi-Fi). No special device driver support is necessary; common protocols are used instead.
- User interface (UI) Control
- UPnP architecture enables vendor control over device user interface and interaction using the web browser.
- Operating system and programming language independence
- Any operating system and any programming language can be used to build UPnP products. UPnP does not specify or constrain the design of an API for applications running on control points; OS vendors may create APIs that suit their customer's needs. UPnP enables vendor control over device UI and interaction using the browser as well as conventional application programmatic control.
- Programmatic control
- UPnP architecture also enables conventional application programmatic control.
- Extensibility
- Each UPnP product can have device-specific services layered on top of the basic architecture.
The foundation for UPnP networking is IP addressing. Each device must have a Dynamic Host Configuration Protocol (DHCP) client and search for a DHCP server when the device is first connected to the network. If no DHCP server is available, that is, the network is unmanaged, the device must assign itself an address. If during the DHCP transaction, the device obtains a domain name, for example, through a DNS server or via DNS forwarding, the device should use that name in subsequent network operations; otherwise, the device should use its IP address.
