QSFP28 (Quad Small Form-Factor Pluggable 28) transceivers are widely used in data center and high-performance computing environments for high-speed data transmission. These transceivers support data rates of 100 gigabits per second (Gb/s) and are designed for various applications. Here are some common types of QSFP28 transceivers:

100G QSFP28

1. QSFP28 SR4 (Short-Range 4):

• Designed for short-distance transmissions over multimode fiber (MMF).

• Typically used for 100GbE connections with a reach of up to 100 meters.

2. QSFP28 LR4 (Long-Range 4):

• Designed for longer-distance transmissions over single-mode fiber (SMF).

• Supports 100GbE connections with a reach of up to 10 kilometers.

• Utilizes wavelength division multiplexing (WDM) technology to transmit four separate wavelengths over a single fiber.

3. QSFP28 PSM4 (Parallel Single Mode 4):

• Designed for longer-distance transmissions over parallel single-mode fiber.

• Supports 100GbE connections with a reach of up to 500 meters.

4. QSFP28 CWDM4 (Coarse Wavelength Division Multiplexing 4):

• Uses CWDM technology to transmit four separate wavelengths over a single fiber.

• Supports 100GbE connections with a reach of up to 2 kilometers.

5. QSFP28 ER4 (Extended Range 4):

• Designed for extended-range transmissions over single-mode fiber.

• Supports 100GbE connections with a reach of up to 40 kilometers.

• Utilizes WDM technology for four separate wavelengths.

6. QSFP28 AOC (Active Optical Cable):

• Incorporates optical transceivers into a cable assembly.

• Eliminates the need for separate transceivers and fiber optic cables.

• Available in various lengths for short-distance connections.

7. QSFP28 DAC (Direct Attach Cable):

• Uses copper cables with integrated transceivers.

• Suitable for short-distance connections within a data center.

• Available in various lengths.

These are just a few examples of QSFP28 transceiver types, and there may be variations or additional options based on specific vendor implementations. The choice of the QSFP28 transceiver type depends on factors such as the required data rate, transmission distance, and the type of fiber infrastructure in the network.