ITS and WAS

Dear Guru,

Is ICM (Internet Communication Manager) that exist in WAS a replacement for ITS (wGate & AGate)? Is the Web Browser talk directly to ICM or there is ITS in between where Web Browser talk directly to ITS first (wGate) ? The architectures in some powerpoint slides didn't clearly state where to put ITS in WAS Architecture. I understand ITS is just an middleware to translate ABAP <-> HTML. Can ICM do that ?

I understand that WebAS 6.4 has ITS integrated inside.

So before WebAS 6.4, is ITS part of WAS or there are two separate entities that has different functions ?

Thanks.