SSIS Memory allocation Is SSIS subject to the maximum memory limitations for SQL Server 2012 Standard edition?

If I have a server with 128GB RAM and I allocate 64GB of RAM to SQL Server does SSIS utilise this memory or does it utilise the memory that is available to the OS?

I am assuming it utilises the remaining memory left to the OS since there is no settings for memory consumption and it runs as a separate service.

If anyone has any information on the available memory that should be left for SSIS to consume I would appreciate the help.
SSIS runs outside of SQL Server's memory space so it's going to be contending with the memory allocated to the OS.

How much memory you allocate to SSIS is entirely dependent on how you define your SSIS packages. To go fast, which is what SSIS is designed for, it's going to push as much data into memory so that operations can be performed on it and slap it into the target system. You might only have 10GB of data from your source system but in theory you could consume more than 10GB of memory by using semi or fully blocking components as they will result in memory copies and such.