WAP mobile phone download service flowchart description

Figure 1-download the logical structure of the Service System

The Content Server is an entity that provides mime content for mobile users. The download server receives download requests from the terminal and manages the transfer of content from the content server to the terminal browser. The content server uses the wap push Service Load to trigger content download. The download server provides the following functions:
Device Storage Capability Management
Data download management
Asynchronous content Transfer

Supported download services include ringtone download, image download, screensaver download, and short video download. In addition, the download service has a standard OTA download server function, which can be used for downloading servers in Java/brew systems.

Typical download processes include MS-initiated download and network-initiated download. Download initiated by the network is as follows:

1) the content server uses the WAP pap Protocol [WAP pap] to send the wap push sl [WAP Sl] Message to the push proxy (WAP Gateway) serving mobile users. When a mobile phone receives an SL notification message, there is a user's interrupt indication in the SL content type. The DF server application URL is displayed in the push SL message. For more information, see section 4th.
2) Push proxy parses the MS address and completes some access control checks (if required ), then, the push SL content type is passed to the MS Browser (the X-wap-Application-ID header indicates the WML user agent ).
3) The WML user Browser executes the SL content and establishes a connection with the pull proxy to download the MMC document specified in the SL content type.
4) ms should replace Proxy: Download with the preset DF server URL. In this event, if the DF server address is not set, but Ms receives a message containing Proxy: Download, the MS Browser should display the error message; the WML user browser performs the WSP get operation on the URL of the specified SL content type. The pull proxy parses the URL and sends it to the DF server application.
5) in the get response message, the DF server constructs and sends MMC documents that contain open operations (indicating that the MS Browser establishes an MMC session) and read Operations (determining the current available storage. The satus-Uri attribute of the MMC document (see section 5th) is a resource related to the DF server.
6) The DF agent performs the post operation on the MMC status document based on the previous request. This document contains the session ID (generated by DF agent) of the MMC-ID attribute and the valid storage capacity in bytes. The MMC document issued by DF server then refers to the session identified by the MMC-ID attribute.
7) dF server compares the size of the object to be downloaded with the valid value of mobile phone storage. If the valid storage size of the mobile phone is less than the downloaded object, send the "out of memory" status message to the Content Server (refer to section 4.3) and send the disconnect operation to the DF agent. Skip Step 8-12.
8) If the mobile phone has enough storage capacity, the DF server constructs and sends MMC documents containing write and commit operations. However, the downloaded object is not submitted to the permanent storage of the mobile phone, unless it has been successfully downloaded (see 5.2.4 ). The value of the download status message as the display. Message Parameter is also included in the MMC document. The status-Uri attribute in the MMC document (see section 5th) is a resource related to the DF server.
9) dF agent downloads the fun object from the URL in the MMC document.
10) the DF agent reports the MMC operation status to the DF server.
11) If the write (s) and commit operations are successful, the DF server constructs another MMC document containing the disconnect operation and sends it to the DF agent to end the MMC session. The status-Uri attribute of the MMC document is either a resource from the content server or a resource related to the DF server. DF server records this transaction.
12) the DF agent performs the post (s) operation on the URL indicated by the Status-Uri attribute in the MMC status to trigger the billing event and (or) return the next card to the browser.
The download service process initiated by MS is similar to the download service process initiated by the network. The difference is that when a user selects a service in the content server, triggered by the URL returned by the content server embedded in the content.