The Cisco QSFP28 to SFP28 Adapter (QSA) Module offers 25. 10 and 1 Gigabit Ethernet Connectivity for QSFP 100G ports. The adapter gives customers flexibility to upgrade to 100GE platforms while maintaining connectivity to lower speed endpoints. The Cisco QSA Module converts a QSFP28 port to an SFP28. SFP+ or SFP port. This flexibility allows customers a cost-effective transition to high density 100G platforms. while maintaining low speed connectivity on select ports.