Specifying a caller in default and general bindings indicates which token or tokens to use to create authentication credentials. When there are multiple tokens on an incoming message, the order of the callers determines which token is used for the credentials. You can rearrange the order of the callers using the administrative console.
Before you can complete this task, you must create a new policy set and attach it to a service, or copy and edit one of the sample system policy sets. For more information, read the topics Creating policy sets using the administrative console and Attaching a policy set to a service artifact. You can also create multiple new callers in the default provider bindings associated with the policy set, as described in the topic Configuring the callers for general and default bindings
The order attribute is assigned only for callers on bindings in WebSphere® Application Server Version 7.0 or later. Bindings created with earlier versions of WebSphere Application Server may have callers, but these callers do not have an order attribute. These callers can appear in the Callers collection table, but do not have an order number in the order column. If these bindings were migrated to Version 7.0 or later, then order attributes must be assigned before saving and using these bindings. You can use the Move up and Move down buttons to assign orders to the callers.