In 10g, dataguard started to support different binaries on primary and standby database servers with the same OS family.
For example :
Microsoft Windows 64-bit on primary and Microsoft Windows 32-bit
Microsoft Windows 64-bit for AMD on standby database server.
However with 11g, dataguard also supports different OS on primary and standby servers. I wanted to share the support matrix for this feature.
Check this Blog which is talking about this topics and post some Notes From My Oracle Support :