Optical transceivers can be divided into 3 categories according to technology: PDH, SPDH, SDH, HD-CVI.

PDH optical transceiver:

PDH (Plesiochronous Digital Hierarchy, quasi-synchronous digital series) optical transceiver is a small-capacity optical transceiver, which is generally used in pairs, also called point-to-point applications.

SDH optical transceiver:

SDH (Synchronous Digital Hierarchy, synchronous digital series) optical transceiver has a large capacity, generally 16E1 to 4032E1.

SPDH optical transceiver:

SPDH (Synchronous Plesiochronous Digital Hierarchy) optical transceiver, between PDH and SDH. SPDH is a PDH transmission system with the characteristics of SDH (Synchronous Digital Series) (based on the principle of code rate adjustment of PDH, and at the same time using part of the networking technology in SDH as much as possible).

Type of interface:

Optical transceivers are classified according to the interface: video optical transceiver, audio optical transceiver, HD-SDI optical transceiver, VGA optical transceiver, DVI optical transceiver, HDMI optical transceiver, data optical transceiver, telephone optical transceiver, Ethernet optical transceiver, switch optical transceiver.