The GigE ports on the MPCD and the GigE director interface boards have a hardware compression chip. Depending on the compressibility of the data, this can lower network bandwidth requirements. The SRDF data is compressed prior to encapsulation into IP packets.
Hardware compression for SRDF traffic over GigE is available through a compression chip:
On the MPCD and GigE director boards (Symmetrix DMX systems)
On the compression-capable Front End I/O Module Carriers (Symmetrix VMAX systems)
Beginning with Enginuity version 5874, software compression can be used along with hardware compression. The result is a better compression ratio.
See Home > Support > Technical Documentation and Advisories > Software ~ S ~ Documentation > SRDF Family > General Reference > EMC Symmetrix Remote Data Facility (SRDF) Connectivity Guide , Page 58
And if you use an FC link to a storage router, the router can do compression for you on the fly while encapsulating FC in ip packets. I've seen the Cisco MDS 9216i reach a 3:1 ratio at it's best