RSA - upgrading key size on clients

3jg13

Hi.
Got a new job, and first task is to upgrade the key sizes on our clients to 2048 bits (from 1024). The code looks like it will sustain the upgrade fine (by that I mean the data types can support very large integers needed for the bigger key size).

My biggest concern (fyi ... fairly new to RSA) is applying this upgrade to our client programs. We have 100s of clients running in the wild and they all communicate with each other encrypted via RSA and all share the same key size as we started with 1024 by default. But now we have to upgrade to bigger key size and the clients will be getting the update at varying times and so there could very well be clients communicating together with different key sizes (one client is 1024 bits and another is 2048 bits).

Is there anything I need to be aware of here? Is there potentially anything that would cause the clients to not communicate together?

Please advise, especially if anyone has any kind of experience with this.

Thanks
Jeff