Quad-SFP (QSFP+ and QSFP28) ports allow for four channels of lower-bandwidth communication.
AOS-CX release 10.05 introduced this feature for select switches and modules.
Most QSFP28 ports can be used with either 40G or 100G optics, DAC or AOC cables. Not all QSFP28 ports can be split into channels of 10G or 25G: what is required are MACs and PHYs that can support both 10G and 25G speeds.
Some designs will allow only splitting into the four (4) channels at 10G because they lack a 25G MAC (for example, the Aruba 8325 Switch Series JL627A 32 port 40G/100G). Some switches/modules also limit only certain ports to be split because of design combinations of PHY/Ports or limitations of the maximum number of MACs in a switching ASIC.
An example CLI configuration for port 1/1/52:
switch(config-if)# interface 1/1/52
switch(config-if)# split
This command will disable the specified port, clear its configuration,
and split it into multiple interfaces. The split interfaces will not
be available until the next system or line module reboot.
Continue (y/n)? y
switch(config-if)# show interface brief
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Port Native Mode Type Enabled Status Reason Speed Description
VLAN (Mb/s)
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1/1/52:1 -- routed QSFP+DA3x4 yes up 10000 Aruba-AP
1/1/52:2 -- routed QSFP+DA3x4 yes up 10000 --