IETF-50 UPnP Update Prakash Iyer Intel Corporation

UPnP Forum Background  Created in June 1999  Open to everyone!  No forum membership fees  Membership agreement required  Certification and logo program being put in place  Over 300 forum members  4 Organizational Components  20-member Steering Committee oversees all Forum activities  Marketing Committee oversees all marketing / PR activities  Technical Committee resolves common technical issues  Working Committees define Device Control Protocols (DCP)  5 WCs and 19 core devices

UPnP Functional Components  Control Point  Initiates discovery and control of devices  E.g. Remote control, PC  Controlled Device  A device that has a Device Control Protocol (DCP) defined for it  DCP is essentially XML templates that describe device behavior and enable control and eventing on a device  E.g. Internet Gateway, printer, HVAC  Bridge  A device that can essentially proxy a legacy or non-UPnP device by offering a DCP service for that device

UPnP Addressing & Discovery  Addressing  Supports Auto IPv4 address configuration, DHCP, link- local IPv4 addresses  IPv6 in future  Discovery  Simple Service Discovery Protocol (SSDP) – HTTP-MU  Uses reserved local administrative scoped mcast address port 1900  Unsolicited advertisements: HTTP/NOTIFY with ssdp:alive  Device unavailable: HTTP/NOTIDY with ssdp:byebye  Device solicitation: HTTP/M-SEARCH with ssdp:discover  UPnP limits TTL to 4 to minimize network congestion

UPnP Description & Presentation  Description  XML templates defined by device-specific working groups a.k.a Device Control Protocols (DCP)  Covers operational and configuration aspects of a device  DCP hierarchy: Devices (containers) and services  Notion of ROOT device  Generically offers GET and SET actions and specifies eventing  Retrieved using HTTP GET  Presentation (Optional)  Web pages / text based UI

UPnP Control & Eventing  Control  XML-based actions, results and errors encoded in SOAP over HTTP over TCP  Uses HTTP/POST or HTTP/M-POST with MAN header for soap envelope  Responses within 30 seconds with HTTP/OK  Eventing  Based on Generic Event Notification Architecture (GENA)  HTTP/SUBSCRIBE with callback URL  HTTP/UNSUBSCRIBE  HTTP/NOTIFY to deliver an event  Events can be moderated  UPnP restricts GENA to HTTP/TCP

Usage Models  Focus for v1.0 is on residential networks  Discovery and control across the Internet likely for v2.0  Needs more work in areas such as security & authorization, scaling discovery, persistent device naming and possibly IPv6  Interim solutions possible:  Outside-in to a residential gateway that also acts as a control point / bridge for other UPnP devices  Outside-in to a gateway that relays requests to a device  Requires NAT and firewall configuration on gateway  Vendor proprietary end-to-end security

Related Architecture Drafts  draft_cai_ssdp_v1_03.txt  draft-box-http-soap-01.txt  Also a W3C technical report  draft-cohen-gena-client-01.txt  None of the above are active IETF drafts  Plus  Drafts in zeroconf working group  Other related standards in W3C  Forum Website is upnp.org  Several documents restricted to members only