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SRDF/S is a limited-distance solution that is typically implemented in campus or metro environments, as follows:
Wide area network (WAN) provides SRDF connectivity over long distances, using telecommunication networks such as IP, synchronous optical networking (SONET), or asynchronous transfer mode (ATM). SRDF/A must be used in all WAN implementations that exceed the distance or latency limitations of SRDF/S.
Whether SRDF/S can be used in campus or metro implementations depends on the bandwidth available for the SAP HANA persistence and the latency of IOPS. SAP HCMT must be used to validate the bandwidth and latency of the SAP HANA persistent storage. The validation results must meet the SAP HANA KPIs for the persistent storage layer, which are also available from SAP. This requirement applies to nonreplicated environments. Consult your SAP representative for exceptions to the KPIs for replicated environments.