Chapter 27. Protocol Versions

The LiveJournal protocol (so far) has been more or less static; while new modes have been added, the basic operation has not changed much. Introduction of Unicode support in LiveJournal necessitated changes in the way text is encoded in protocol requests and responses. To allow new clients to take advantage of Unicode support and at the same time avoid breaking existing clients, a versioning scheme was put into the protocol. The client sends the number of the highest protocol version it supports in every request, inside a ver attribute; version 0 is implicit if the client does not send the ver attribute. Currently there are two versions of the protocol, and the Unicode-enabled server code supports both of them.

[19] See the Unicode Consortium[o] website for more information on Unicode and UTF-8.