- Casey
Harper Ross
Answered on 7:03 am
QSFP28, QSFP56 and SFP56 are abbreviations for different types of optical transceivers or cables that use the QSFP or SFP form factor and support different data rates. The general format is XG-Y, where X is the data rate in gigabits per second (Gbps), and Y is the number of lanes or the modulation scheme used.
The emergence of PAM-4 signaling has increased the types of interfaces available in QSFP and SFP form factors. The table below summarizes how Arista describes each media type.

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