Problem:
From the mongod process its not clear what drivers are communicating to the server and which versions. In mixed environments this get even more complex, esp if there is a issue caused by a specific client / driver.

Solution:

• allow the driver to add a sub-document into the BSON sent that allows it to define driver specifc information, for example
  • driver version
  • language
  • client side config (e.g. timeouts)

Benefits:

• added information that could help more accurately diagnose issues
• more information means less information a customer has to be asked to diagnose a problem
• information could be displayed in MMS
• enable easy identification of clients that would require an upgrade, e.g. PHP 5.2 being phased out, specific bug in Java driver that customer needs to upgrade to avoid

Downsides:

• messages would increase in side, if done per message
• could be avoid if info passed when connection is established