SFP Can be Plugged into SFP+ Ports in Most Situations
I’m not sure about the specific switch model, but as a general rule of thumb, SFPs will work in SFP+ slot, but SFP+ optics do not work in SFP slots. It’s just a power availability thing. When you plug the SFP module in SFP+ port, the speed of this port is 1G not the 10G. And sometimes this port will lock the speed at 1G until you reload the switch or do some fancy set of commands. Besides, the SFP+ port usually can never support speed under 1G. That is to say, we can’t plug the 100BASE SFP in the SFP+ port. In fact, for this question, it may depend greatly on the switch models – sometimes SFPs are supported in SFP+ ports, and sometimes not. For example, almost all SFP+ ports of Cisco switch can support SFPs and many SFP+ ports of Brocade switch only support SFP+. Though it’s feasible often, it’s safer to ask your switch vendor for some information.