Operate and Manage the Experience Service > Managing Your Experience Service > Identity Resolution Service (IRS) Federation
  
Identity Resolution Service (IRS) Federation
When an Experience Service receives a query for Experiences associated with a ThingMark, it responds as follows:
1. The Experience Service collects any Experiences hosted locally that are associated with that ThingMark.
2. If the ThingMark does not belong to the domain assigned to the Experience Service and the Experience Service is federated, it then forwards the query to the GXI to collect any Experiences hosted by the Experience Service assigned to that domain.
3. The Experience Service returns the union of the two sets of Experiences to the client that submitted the query.
An Experience Service can be configured to be federated or not federated. When an Experience Service is federated, it performs Step 2. If the Experience Service is not federated, then it does not perform Step 2 and only returns Experiences that are hosted locally. The enable_irs_federation configuration parameter is used to determine whether an Experience Service is federated or not. For more information about configuring the enable_irs_federation configuration parameter, see Configuration Parameters.