Multi-Tier Session Rule Concepts Session rules are declarative in nature and template driven. You build a template that determines how one or more Multi-Tier Client components are going to interact with a particular instance of a Multi-Tier Server component (Database Agent or Service Provider Agent). Session rules also determine which Multi-Tier Server component is instantiated, and how it is to be instantiated for a particular Multi-Tier Client.The basic Session Rule unit is a Multi-Tier Connection Attribute, each representing a key aspect of a Multi-Tier Client's connection to a Multi-Tier Agent Session. There are six Multi-Tier Connection Attributes: Domain User OpSys Machine Application Mode