12 Networked Bookmark Service

26.2373GPPIP Multimedia Subsystem (IMS) based Packet Switch Streaming (PSS) and Multimedia Broadcast/Multicast Service (MBMS) User ServiceProtocolsRelease 17TS

Bookmarking allows a user receiving a content item at an UE to mark a point in time in the streamed content which he can access at a later time. The content item is CoD delivered by a PSS server.

The user can later retrieve the bookmark from any device on which he is registered.

The XML schema used for networked bookmark service is defined in Annex J.

12.1 Bookmarking Creation and Storage

The call flow in Figure 27 depicts the sequence for creating a bookmark for a CoD item and storing it in the user’s service profile for later retrieval.

Figure 27: IMS-based Content Bookmark creation and Storage

The following is a brief description of the steps:

1. The UE has established a CoD session. At some point in time, the user decides he wants to create a bookmark. If the UE does not have the current play out position, it sends an RTSP GET-PARAMETER request to the PSS server to request it.

2. The response to the RTSP GET-PARAMETER request is returned by the PSS server in an RTSP 200 OK.

3. The UE sends to the IM CN Subsystem a SIP INFO Message that includes the Content-Bookmark Info package as well as the CoD content id. The Content Type shall include the registered MIME type of XML documents representing bookmarking data, and shall be set to "application/3gpp-ims-pss-mbms-bookmark+xml" (see Annex J).

4. The IM CN Subsystem forwards the SIP INFO Message to the SCF.

5. The SCF issues an XCAP request, on behalf of the user, to update the service profile with the Content-Bookmark Info data.

6. The Service Profile returns the response to the SCF.

7. The SCF returns a SIP 200 OK to the IM CN Subsystem.

8. The IM CN Subsystem forwards the SIP 200 OK to the UE.

12.2 Bookmarking Retrieval

Once a bookmark is created, a user can later retrieve the bookmark anytime, e.g. prior to or during PSS session establishment procedure, from any device on which he is registered.

Clause 12.2.1 depicts the bookmarking retrieval procedure which is independent to PSS session establishment procedure, and clause 12.2.2 depicts the bookmarking retrieval procedure during a PSS session establishment process.

12.2.1 Bookmarking Retrieval independent to session establishment

The call flow in Figure 28 depicts the bookmark retrieval procedure for retrieving bookmarks stored in the user’s service profile.

Figure 28: Bookmark retrieval independent to session establishment

The following is a brief description of the steps:

1. The UE issues an XCAP GET request to the Service Profile to request the bookmarks.

2. The bookmarks are returned in an HTTP 200 OK response.

12.2.2 Bookmarking Retrieval during session establishment

The call flow in Figure 29 depicts the bookmark retrieval procedure for retrieving bookmarks stored in the user’s service profile during a PSS session establishment process.

Figure 29 Bookmark Retrieval during session establishment

1) The UE sends an SIP INVITE to the SCF via the IM CN Subsystem.

2) The IM CN Subsystem forwards the SIP INVITE to the SCF.

3) The SCF validates the SIP INVITE request, and checks the rights of user for the requested content by sending an XCAP GET with the user ID and content identifier to the Service Profile.

4) The Service Profile authorizes the user, and returns the user’s service profile with the bookmark list if it is set before. Each bookmark in the list should contain at least the content ID and the time reference.

5) The SCF selects the appropriate PSS Adapter for the requested content, and sends the SIP INVITE to the PSS Adapter via the IM CN Subsystem. The PSS Adapter then selects the PSS Server and sends the RTSP SETUP to the PSS Server.

6) The PSS Server returns an RTSP 200 OK to PSS Adapter, which returns a SIP 200 OK to the SCF via the IM CN Subsystem.

7) The SCF returns the SIP 200 OK to the UE via the IM CN Subsystem, with the bookmark list.

8) The IM CN Subsystem forwards the SIP 200 OK to UE.

9) The UE plays out the bookmark list to the user, and the user selects the bookmark from which they wish to start viewing the content.