J.2 GPI delivery using WAP Push
24.1093GPPBootstrapping interface (Ub) and network application function interface (Ua)Protocol detailsRelease 17TS
J.2.1 General
When the GPI data object is delivered using SMS, the Push-NAF and the UE shall use the Push OTA protocol over WSP as defined in OMA’s "Push Over the Air" specification [26] for connectionless non-secure push.
J.2.2 Push-NAF procedures
In order to send the GPI via WSP, the Push-NAF shall construct a push message according to OMA’s "Push Message Specification" [27] and shall populate the push message as follows:
– the Content-Type header shall include the MIME media type ‘application/vnd.3gpp.gba.gpi’ or the corresponding short code as defined in clause J.3.1.3.
– the X-WAP-Application-ID header shall include the application-id associated with the specific GBA User Agent or the corresponding short code, if available for the application in question. The short code for the identifier of a specific application is defined in the corresponding specification for the application.
– the Session Identifier shall be different between different GBA Push initiated sessions for the same recipient. All messages in the associated OMA DM session shall include the Session identifier as Session ID.
– the message body shall contain the GPI envelope as described in clause J.3.1.2 with the version field set to 1, the session identifier set by the server, as specified in sublause J.3.1.2, and GPI field set to the GPI.
NOTE 1: One SMS can carry 140 bytes of information and the GPI message fits into a single SMS when short codes are used for the Content-Type and X-WAP-Application-ID attributes, as described in clause J.3. When short codes are not defined, or not used, the WAP Push message does not fit into a single SMS message and then concatenated SMS messages are used.
The general format of the GPI push message within one SMS message is shown as an example in table J.2-1.
Table J.2-1: Example of a GPI Push message with header and content in one SMS
|
Binary Value |
Bytes |
Meaning Description |
|
WDP headers starts |
||
|
06 |
1 |
User-Data-Header (UDHL) Length = 6 bytes WDP layer |
|
05 |
1 |
UDH IE identifier: Port numbers |
|
04 |
1 |
UDH port number IE length |
|
0B |
1 |
Destination port (high, Port number 2948 |
|
84 |
1 |
Destination port (low), Port number 2948 |
|
Orig.port |
1 |
Originating port (high), Port number freely chosen by sender |
|
Orig.port |
1 |
Originating port (low), Port number freely chosen by sender |
|
End of WDP headers, |
||
|
Trans.id |
1 |
Transaction ID / Push ID WSP layer |
|
06 |
1 |
PDU type (push) |
|
03 |
1 |
Headerslength (content type+headers) |
|
Cont.Type |
e.g. 1, NOTE 1 |
Content type code MIME-Type AF X-WAP-Application-ID, see clause J.3.1.3. |
|
Appl.Id |
e.g. 2, NOTE 2 |
Application Id |
|
End of WSP header, start of GBA specific information |
||
|
01 |
1 |
Version, see clause J.3.1.2. |
|
Sess.Id |
2 |
16 bit integer for Session-ID, see clause J.3.1.2 |
|
Varying |
GPI |
|
|
NOTE 1: The length depends on the allocated short code; 1-4 bytes. This is 1 byte for OMA DM Notifications. |
||
|
NOTE 2: The length depends on the allocated short code; 2-4 bytes. This is 2 bytes for OMA DM Notifications. |
||
NOTE 2: If the GPI Push message needs to be sent in more than one SMS, the segmentation information is added in 5 bytes to the WDP headers in each SMS (in total 7+5=12 bytes). The 5 added bytes are Type 0x00, len 0x03, Message Reference Number (byte) for concatenation, Current Segment Number (byte) and Total Segment Count (byte).
J.2.3 UE procedures
J.2.3.1 Reception of GPI in push message
Upon receiving a push message on the IANA registered WDP port 2948 according to OMA’s "Push Message Specification" [27] where:
– the Content-Type header indicates the application/vnd.3gpp.gba.gpi MIME type as defined in clause J.3.1.4 or the the corresponding short code as defined in clause J.3.1.3; and
– the X-WAP-Application-ID header indicates an application supported by the UE;
the UE shall extract GPI from the GPI envelope according to clause J.3.1, check the integrity of the GPI and use the Application-ID to locate the corresponding application in the UE. The UE uses the content of the push message to establish a connection with the indicated server. All messages in the associated OMA DM session shall include the Session identifier (Session ID) as received from Push-NAF.
NOTE: As indicated in OMA DM Enabler Release v1.2 [28] it is also possible to send WAP Push messages using some other transport than SMS, if the UE for example does not support SMS. OMA’s "Push Message Specification" [27] also specifies OTA-HTTP and OTA-SIP, which can be supported by the UE.