Another use for SMS is configuring phones over the air (OTA). There are elaborate standard specifications written by the WAP Forum (now Open Mobile Alliance) and somewhat proprietary standards developed by Nokia and Ericsson.
Today I’ll show in detail how to send a bookmark according the Nokia / Ericsson specification. The specification is somewhat older, it dates from September 2001, but it seems almost all Nokia and many Ericsson devices still support this.
The bookmark is described in an XML file like the following:
<?xml version="1.0"?>
<!DOCTYPE CHARACTERISTIC-LIST SYSTEM "settings.dtd">
<CHARACTERISTIC-LIST>
<CHARACTERISTIC TYPE="BOOKMARK">
<PARM NAME="NAME" VALUE="Mobile Tidings"/>
<PARM NAME="URL" VALUE="http://mobiletidings.com"/>
</CHARACTERISTIC>
</CHARACTERISTIC-LIST>
As before we send this XML document using an unconfirmed push. Here are the layers we need to implement:
- the XML document needs to be WBXML encoded and
- the WBXML need to be wrapped in a WSP (Wireless Session Protocol) Push PDU
- this needs to be wrapped in a WDP (Wireless Datagram Protocol) packet
- this needs to be sent inside an SMS
As always we start with the AT command that is used to send the bookmark and analyze in detail how this AT command was constructed:
AT+CMGS=133 0041000B915121551532F40004780B0504C34FC0020003F001010A062D1F2B6170706C696361 74696F6E2F782D7761702D70726F762E62726F777365722D626F6F6B6D61726B730081EA0101 6A0045C67F01871511034D6F62696C6520546964696E6773000187171103687474703A2F2F6D 6F62696C65746964696E67732E636F6D00010101
Here is a byte-for-byte explanation:
| Size | Value | Description | Section |
| 1 octet | 0×00 | No SMSC supplied | SMS |
| 1 octet | 0×41 | SUBMIT-PDU + UDH present | |
| 1 octet | 0×00 | message reference | |
| 1 octet | 0x0B | Length of destination address in digits | |
| 1 octet | 0×91 | Destination is an international telephone number | |
| 6 octets | 0x5121551532F4 | Destination is ‘+15125551234’ | |
| 1 octet | 0×00 | Protocol identifier | |
| 1 octet | 0×04 | Date coding scheme. This value stands for ‘8 bit data’. | |
| 1 octet | 0×78 | User Data Length. Size of payload is 120 octets. | |
| 1 octets | 0x0B | User data header length is 11 octets. | UDH |
| 1 octet | 0×05 | IEI 0×05 contains source and destination port. | |
| 1 octet | 0×04 | IEDL. Content is 4 octets. | |
| 2 octets | 0xC34F | Destination port is 49999. This is the port for OTA configuration. | |
| 2 octets | 0xC002 | Source port is 49154. | |
| 1 octet | 0×00 | IEI 0×00 contains concatenation information | |
| 1 octet | 0×03 | EIDL. Content is 3 octets. | |
| 1 octet | 0xF0 | Reference number | |
| 1 octet | 0×01 | Total 1 parts | |
| 1 octet | 0×01 | This is the 1st (and only) part | |
| 1 octet | 0x0A | The WSP transaction ID | WSP |
| 1 octet | 0×06 | This is a push PDU | |
| 1 octet | 0x2D | Headers consist of 45 octets | |
| 1 octet | 0x1F | Indicates that the length is greater than 30 octets. | |
| 1 octet | 0x2B | Length is 43 octets. | |
| 40 octets | 0x6170706C6963 0x6174696F6E2F 0x782D7761702D 0x70726F762E62 0x726F77736572 0x2D626F6F6B6D 0x61726B73 |
Content type: “application/” ”x-wap-prov.browser-settings” |
|
| 1 octet | 0×00 | end of string | |
| 1 octet | 0×81 | Parameter name: 0×01 means ‘Charset‘ | |
| 1 octet | 0xEA | Parameter value: 0x6A means ‘UTF-8‘ | |
| 1 octet | 0×01 | WBXML Version 1.1 | WBXML |
| 1 octet | 0×01 | Unknown document type. | |
| 1 octet | 0x6A | Encoding UTF-8 | |
| 1 octet | 0×00 | String table length | |
| 1 octet | 0×45 | <CHARACTERISTIC-LIST> element, with content | |
| 1 octet | 0xC6 | <CHARACTERISTIC> element, with content and attributes | |
| 1 octet | 0x7F | attribute with value ’TYPE=BOOKMARK’ | |
| 1 octet | 0×01 | end of <CHARACTERISTIC> attributes | |
| 1 octet | 0×87 | <PARM> element with attributes | |
| 1 octet | 0×15 | attribute with value ‘NAME=NAME’ | |
| 1 octet | 0×11 | attribute ‘VALUE’ | |
| 1 octet | 0×03 | Inline string follows | |
| 14 octets | 0x4D6F62696C65 0x20546964696E 0×6773 |
“Mobile Tidings” | |
| 1 octet | 0×00 | end of inline string | |
| 1 octet | 0×01 | end of <PARM> attributes | |
| octet | 0×87 | <PARM> element with attributes | |
| 1 octet | 0×17 | attribute with value ‘NAME=URL’ | |
| 1 octet | 0×11 | attribute ‘VALUE’ | |
| 1 octet | 0×03 | Inline string follows | |
| 24 octets | 0x687474703A2F 0x2F6D6F62696C 0x65746964696E 0x67732E636F6D |
“http://mobiletidings.com” | |
| 1 octet | 0×00 | end of inline string | |
| 1 octet | 0×01 | end of <PARM> attributes | |
| 1 octet | 0×01 | end of <CHARACTERISTIC> element | |
| 1 octet | 0×01 | end of <CHARACTERISTIC-LIST> element |
