What is the Difference Between QSFP28 and 100G QSFP?

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FiberMall

Answered on 5:48 am

QSFP28 and 100G QSFP essentially refer to the same thing. Both terms are often used interchangeably to describe a kind of high-speed transceiver module that’s used in networking hardware.
QSFP stands for “Quad Small Form-factor Pluggable,” and it’s a standard developed for high-speed data communications. QSFP28 is a specific type of QSFP module that’s designed to carry 100 Gigabits per second, hence the term 100G QSFP.
The “28” in QSFP28 refers to the maximum Gigabits per second that each of the four channels in the module can carry. So with QSFP28 (or 100G QSFP), you have four channels each capable of carrying 25 Gigabits per second (4x25Gbps), giving a total of 100Gbps.
So, there isn’t really a difference between QSFP28 and 100G QSFP. They’re just different names for the same technology, and they both refer to a QSFP transceiver that’s capable of delivering 100 Gigabits per second of data transfer.

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