How to have two instances of JIRA to cross communicate as one instance

[Claude Allain]

We currently have two instances of JIRA, one for ITS and one for Engineering. The company now has joint development for specific projects between ITS and Engineering. What we would like to do is configure JIRA so that cross comunication can occur over different Projects across both instances of JIRA residing on different servers.

[Norman Abramovitz]

Can you define better what you mean by cross communication since there are multiple interpretations and how much effort/cost you can put into your solution? For example, is the ITS and Engineering workflows serial or parallel to each other? Are their workflows the same or different? Can you get away with each group just viewing each others states? You cannot share databases between Jira instances today, but can you invest time/cost into writing to a third database which is designed for concurrent/parallel access?

[V]

It's very interesting and awaiting for answers .