SIP file directory with presence SUBSCRIBE sip:bob@example.com Event: presence 200 OK 200 OK PUBLISH Event: presence PIDF including a resource description of available files 200 OK NOTIFY Event: presence PIDF including a resource description of available resources: files, printers, etc. Now Alice is aware of the list of available files at Bob’s mobile device and laptop 200 OK PUBLISH Event: presence PIDF including a resource description of available resources: files, printers, etc. |