Adding a module to existing multi-module system

Real Example - A customer with an existing software system, 2 existing modules, is adding a third module which has not been released yet and thus revenue cannot be recognized yet. Issue - How should deal be structured so that the existing, reliable revenue stream can be recognized and the new module's revenue is deferred? Resolution - This can be done as long as the new module is not intertwined into the functionality of the older system. For example, if the system fundamentally changes with the new module, such as upgrading from Windows 95 to Windows 2000, then the new module is not truly separate. However if the new module is like adding Excel to a system that has Word and Outlook, then revenue for the incumbent modules can continue to be recognized. Other indicators that the new module is separate from the current system and modules include:

1. If the new module's contract is separate and does not tie into the original deal.
2. If the new module's contract does not change the terms, or fee of the original deal.
3. If the module's sale is not linked to the renewal of the existing deal.
4. The customer is currently happy with their current system and paying their bills.
5. The customer would continue paying their bills should the new module's roll out be problematic.