Web Services Discovery and Web Services Devices Profile

Web Services Discovery and Web Services Devices Profile Toby Nixon Co-Chair, OASIS WS-DD TC toby. nixon@microsoft. com

Networked Device Standards “The Great Thing about Standards is… … there are so many to choose from!” 2

Industry Challenges • Non-interoperable or gateways required – And often gateways not available • • • Proprietary physical interfaces Tied to single physical layers Non-standard link protocols Platform- or runtime-specific Not extendable – Limited opportunity for innovation • Not scalable • Limited, if any, development tools • Security 3

Web Services • Interoperable machine-to-machine interaction over a network – Programmatic interfaces • Messages formatted using XML (Extensible Markup Language) • Simple Object Access Protocol (SOAP) • Web Services Description Language (WSDL) 4

Benefits of Web Services • • • 5 Work on any physical network Standard protocols: TCP/UDP/IP, HTTP, XML Not platform- or runtime-specific Scalable from smallest device to the internet Extendable by vendors and orgs Excellent development tools from many vendors, and many trained developers Secure High performance Many infrastructure components available Leverage industry investments

UPn. P – 1 st Generation • Rolled out in 1999 – UPn. P Forum created – 10 th Anniversary is this fall • Web services were in their infancy – HTTP, XML, SOAP… not much else – UPn. P is based on an early snapshot • But many benefits from just these basics, so industry moved ahead with UPn. P adoption – Most adoption for NAT traversal and media sharing – UPn. P supported in Windows since Windows ME 6

UPn. P Status • UPn. P Forum now has over 880 members – UPn. P Forum was incorporated in January, 2009 • 72 UPn. P specifications were published as ISO/IEC standards in December, 2008 – UPn. P Device Architecture 1. 0 – DCPs: Basic Device, AVv 1, AVv 2, Digital Security Camera, HVAC, Lighting, Internet Gateway, Printer, Scanner, QOSv 1, QOSv 2, Remote. UI, Device Security • New specifications not yet submitted to ISO/IEC – Done: UDA 1. 1, Low Power, AVv 3 and QOSv 3 – Work in Progress: Remote Access, Content Sync, Device Management, Telephony, AVv 4 7

DPWS – 2 nd Generation • UPn. P 2. 0 was proposed in 2002 – Full alignment with Web Services architecture – Lightweight profile of Web Services specifications appropriate for embedded device applications – Work suspended because some specs not ready, including Discovery and Eventing • Work started on Devices Profile for Web Services, WS-Discovery, and WS-Eventing – BEA, Canon, Computer Associates, IBM, Intel, Lexmark, Microsoft, Ricoh, Software. AG, and TIBCO worked on various components – Industry workshops and plugfests – DPWS first published in 2004 8

How It Works • • 9 Addressing – automatic assignment Discovery – automatically find devices Description – what can the device do? Control – invoke device functions Eventing – monitor device state Presentation – use device’s web interface Security – authentication, integrity, privacy

Addressing • Address assignment not detailed in DPWS – But typical implementations all work the same way • IPv 4 – Attempt DHCP address assignment – If fails, use “Auto-IP” (RFC 3927) self-assigned local address (169. 254/16) – Check periodically for DHCP server – Static IP addresses also permitted • IPv 6 – Obtain address from DHCP or Router – Or use self-assigned Unique Local Address (RFC 4193) 10

Discovery • WS-Discovery – Being standardized in OASIS WS-DD along with DPWS • Device multicasts “Hello” when joins network • Client requests address using “Resolve” – Device responds using “Resolve. Match” • Clients can search using multicast “Probe” – Devices respond using “Probe. Match” • Device multicasts “Bye” when leaving • WS-Discovery also defines “discovery proxy” server role for managed networks, scalability 11

Description • Client uses WS-Transfer to Get device description information – This. Model: e. g. manufacturer name, model number – This. Device: user-assigned name, serial number, firmware version – Relationship: List of device types and services available on device, and their WS-Addressing EPRs • Client can use WS-Metadata. Exchange Get. Metadata to download WSDLs for services – Data types, Port types, Operations, Messages – Used more at development time rather than run time 12

Control • Actions defined in the service WSDL are invoked using SOAP over HTTP • Responses returned using SOAP over HTTP 13

Eventing • WS-Eventing – Being standardized in W 3 C WS-Resource. Access WG • Clients Subscribe to event notifications – Address to deliver events – Desired duration of subscription – Optional filter expressing events of interest • Service sends SOAP messages to client to deliver event notifications • Client can Renew subscription, or Unsubscribe • Service can send Subscription. End to terminate subscription before expiration 14

Presentation • Enables web interface to device • Presentation. URL is included in This. Model metadata element • Client uses browser (HTTP GET) to use device’s web interface • Metadata also includes – Manufacturer. URL – Model. URL 15

Security • Optional • Secure devices must have X. 509 v 3 certificate – Should be unique for each device instance • Based on SSL/TLS (https: //) – Establish secure channel for description, control, and eventing for authentication, integrity, and confidentiality – Device can require either X. 509 certification or username/password authentication of client • Multicast WS-Discovery messages authenticated and integrity-checked using Compact XML Signatures 16

UPn. P – DPWS Comparison UPn. P DPWS Addressing DHCP, Auto. IP Not Defined Discovery SSDP WS-Discovery Description UDA Schema WSDL Control SOAP 0. 9, 1. 1 SOAP 1. 2 Eventing GENA WS-Eventing Presentation HTTP, HTML 17

DPWS – Subset of WS-* Suite Non-DPWS WS-Federation WS-Management Workshop Member Submitted Devices Profile WS-Discovery UDDI WS-Atomic Transaction WS-Trust WS-Security WS-Reliable Messaging WS-Coordination WS-Transfer WS-Enumeration WS-Eventing SOAP WS-Addressing MTOM XML Infoset 18 Metadata Assurances WS-Secure Conversation XML 1. 0 Infrastructure and Profiles Standard WS-Metadata Exchange WS-Policy Messaging XML Schema SOAP / UDP XML Namespaces MIME WSDL SOAP / HTTP Foundation

DPWS Standardization • OASIS WS-DD TC – Web Services Discovery and Web Services Devices Profile Technical Committee – http: //www. oasis-open. org/committees/tc_home. php? wg_abbrev=ws-dd – Co-proposed by CA, Canon, Lexmark, Microsoft, Nortel, Novell, Progress Software, Red Hat, Ricoh, Schneider Electric, Software AG, and WSO 2 • DPWS, WS-Discovery, and SOAP-over-UDP – Not any specific device classes • • 19 First Meeting September, 2008 in Redmond Quarterly face-to-face meetings, weekly calls Original Goal: Completion by 2 nd quarter 2009 OASIS Final Approval vote is June 16 -30, 2009

DPWS Standardization • WS-DD Charter Clarified May 7, 2009 – TC will continue in maintenance mode until closed – Update DPWS to refer to W 3 C Recommendation versions of WS-Eventing, WS-Transfer, and WSMetadata. Exchange; profile as necessary – Update to WS-I Basic Profile 2. 0 if available – Deferred issues, spec issues, errata – Further work on Security if needed – DPWS 1. 2 completion dependent on completion of work in W 3 C WS-Resource. Access WG 20

DPWS Stacks • Microsoft – Windows Vista and Windows 7 • Printers, Scanners, Conference room projectors • Discovery of computers and users – – Windows Embedded CE 6. 0 R 2 Windows XP Embedded. net Micro Framework 3. 0 Biztalk Server 2008 • RFID readers • Other stacks – Levitate, Peerless, SOA 4 D, g. SOAP, e. SOL, Dot. Vision, DPWS 4 J 21

DPWS Implementations • Printers and Scanners – Canon, HP, Xerox, Epson, Lexmark, Brother, Konica. Minolta, Fuji-Xerox, Toshiba, Ricoh, others • Projectors – Epson, NEC, Toshiba – Several others coming • Industrial and home control – Schneider, Hager, Le. Grand, Beckhoff, Vantage – Exceptional Innovation • Audio, Video, home control, hotel control • Over 1000 deployments in USA – Disney Home of Tomorrow • Thousands of devices, 50 K visitors in first week 22

Future DPWS Applications • • • 23 Point of Service Energy Management Network Infrastructure Healthcare Hospitality Factory Automation Mobile devices Automotive Many more…

What About Device Schemas? • OASIS WS-DD will not define device class specifications/schemas – outside of scope • No SIG or other organization for DPWS – Nothing like UPn. P Forum for DPWS – No DPWS-specific certification or logo program • Individual device classes might have them • Any organization can reference DPWS – Device schema specifications should be prepared in the most appropriate existing industry organization – OASIS would be a great home for a device class when no other organization takes ownership • Your organization can start today! 24

Thanks! Questions? 25