1. Page 1 PSI PSI Overview Discovery Strategy The strategy will not mandate any particular Discovery protocol, however, it will suggest Discovery protocols to use. Current thinking in the external group is to use: 0) Pre-configuration 1) SLPv2 - requires no infrastructure and can filter on attributes 2) SSDP - good in a Microsoft environment, may need other protocols such as UPnP to learn about attributes. No DNS required 3) DNS-SD - requires infrastructure, better in heterogeneous environments. No DNS server if multi-cast DNS is used. ----- Registries 4) LDAP? 5) UDDI - Believe this is both under deployed and does not give us what we need. Also it is OK if a particular implementation uses a different strategy when it has knowledge of how PSI will be deployed.

2. Page 2 PSI PSI Overview WSDL Return Example Start with an http get to: http:// :3700/psi ** The hostname Is Discovered Using Existing Discovery Protocols Client Print Service Query EndPointsInterface QuerySupportedInterfaces(): string[] InterfaceIdentifier.xsd: Name, Version, Data Model, Secure QueryInterface (interfaceIdentifier : String) : lang.String Returns Interface - WSDL XML Document for requested interface. ** IANA. Internet Assigned Numbers Authority – Request Pending HTTP Get on http:// :3700/psi Returns Interface - WSDL XML Document for QueryEndPointsInterface Optionally Returns an Array of InterfaceIdentifiers Host

3. Page 3 PSI PSI Overview HTTP URL Return Example Client Print Service Query EndPointsInterface QuerySupportedInterfaces(): string[] InterfaceIdentifier.xsd: Name, Version, Data Model, Secure QueryInterfaceEndPoint (interfaceIdentifier : String) : lang.String Returns HTTP URL EndPoint for the requested interface ** IANA. Internet Assigned Numbers Authority – Request Pending HTTP Get on http:// :3700/psi Returns HTTP URL EndPoint for the QueryEndPointsInterface Optionally Returns an Array of InterfaceIdentifiers Host Start with an http get to: http:// :3700/psi ** The hostname Is Discovered Using Existing Discovery Protocols

4. Page 4 PSI PSI Overview HTTP URL Return Example Client Print Service Query EndPointsInterface QuerySupportedInterfaces(): string[] InterfaceIdentifier.xsd: Name, Version, Data Model, Secure QueryInterfaceEndPoint (interfaceIdentifier : String) : lang.String Returns HTTP URL EndPoint for the requested interface ** IANA. Internet Assigned Numbers Authority – Request Pending HTTP Get URL EndPoint with ?WSDL appended Optionally Returns an Array of InterfaceIdentifiers Host Obtaining the WSDL from the HTTP URL EndPoint Returns Interface - WSDL XML Document for QueryEndPointsInterface HTTP Get URL EndPoint with ?WSDL appended Returns Interface - WSDL XML Document for the requested interface

5. Page 5 PSI PSI Overview HTTP URL Client Side Usage Client ** IANA. Internet Assigned Numbers Authority – Request Pending HTTP Get on http:// :3700/psi Returns HTTP URL EndPoint for the QueryEndPointsInterface Host What does the client do with the return from the HTTP Get? // Make a service JobControlInterfaceService jcService = new JobControlInterfaceServiceLocator(); // Now use the service to get a stub which implements the SDI. JobControlInterface jc =jcService.getOrgPwgPsiJobControlInterface(new java.net.URL( "http://localhost:8080/axis/services/org.pwg.psi.JobControlInterface"));