Question:

Windows IIS supports HTTP Compression... can this be enabled on my site?

Answer:

Shared hosting customers:  IIS's HTTP Compression is not supported on our shared hosting solutions at this time.

Dedicated server hosting customers: IIS's HTTP Compression may be supported on DM (dedicated managed) servers, please submit a support request for additional details, considerations.  For DU (dedicated unmanaged) servers, you have RDP access with admin priveleges, and can implement this feature if you choose to.