TAG-BASED SCHEMA FOR DISTRIBUTING UPDATE METADATA IN AN UPDATE DISTRIBUTION SYSTEM

A tag-based structure for communicating software update metadata information to client computers and to update service nodes is presented. An update metadata file includes: an identifier tag including a software update identifier that uniquely identifies the software update; zero or more general properties tags that carry general property information relating the software update; zero or more localized properties tags that carry localized property information organized according to language; zero or more relationship tags that identify dependency relationships the current software update, as described in the update metadata, has with other software updates; zero or more applicability rules tags that carry information for determining the applicability of the software update to a client computer; zero or more files tags that carry information relating to the software update's payload files; and handler specific data tags that carry information directed to the software handler for installing the software update.