The following steps involve authenticating each application to the other, i.e. Salesforce to Jira and Jira to Salesforce, using an integration user account in each application selected for this purpose.
All transactions, messages, and actions are submitted to the other application using this account. Following authentication via these steps, an OAuth token is retrieved and used in subsequent exchange.
Permissions and restrictions associated with each account may be used to control the scope of the actions that can be performed on behalf of all of the users.
Please also see: zAgileConnect JIRA Integration User required permissions