SyncML®: Synchronizing and Managing Your Mobile Data By Uwe Hansmann, Riku Mettälä, Apratim Purakayastha, Peter Thompson, Phillipe Kahn
Table of Contents
Chapter 6. Representation Protocol
All the examples in this chapter so far have used text encoding, or XML encoding. It is worth noting that SyncML also provides binary encoding WXBML [WBXML01]. WBXML is the preferred method of encoding when operating over limited bandwidth media. Conversion from XML to WBXML is done by replacing the verbose tags with binary tokens. These binary tokens can have a value from 1 to 127 (0x00 to 0x8f). With the limitation of only 127 tags, it is necessary to sometimes use a different "code page" to continue the token representation for a common DTD. In fact, the first possible token is the flag for changing code pages. The SyncML Representation binary tokens can be found in section 8 of the Representation Document.
Note when using the Meta information or the Device Information, a code page switch is necessary. The tags for the MetInfo page are defined in the Meta Information Specification. The tags for the Device Information space are defined in the Device Information Specification. Also note that the Device Information does not use the same code space as the SyncML Representation and Meta Information.
Examples of WBXML may be found in the SyncML Synchronization Protocol document, as well as in Chapter 7.