There are many different types of transceiver footprints. These are just some of the more popular designations that describe the outer housing and the keying of the electrical contacts for the particular transceiver form factor. Transceivers are pluggable
devices that insert into “cages
” on the switch gear and server equipment. The transceivers may also use WDM, in conjunction with parallel optical transmission (SDM), for increased channel
data transmission speeds.2
Transceiver applications and developments
transceivers can be used as standalone devices that plug into the cages of the active switching and server equipment in a data center. In this application, factory terminated patch cords are connected from active equipment’s transceivers to a cross connect
Pluggable optical transceivers also contain special code or firmware
that is “burned-into” the electrically erasable programmable read-only memory (EEPROM) at the factory. The firmware resides as part of the transceiver electronics and allows the switch to identify the transceiver as a compatible device.
Transceivers can also be “built-into” molded cable assemblies such as the direct attached cables (DACs) or active optical cables (AOCs). Two key advantages of these types of cables are lower end-to-end connection losses, because the cabling is factory pre-terminated to twinax copper cables or to factory pigtailed
multi-fiber cables, and the elimination of the need for time-consuming field cleaning and inspection of fiber optic connectors and port receptacles.
Non-pluggable, On-Board Optic
(OBO) transceivers, may also be located right on the PC board in the active switch gear and other devices such as optical multiplexers and amplifiers. This type of solution eliminates the need for a separate metal transceiver housing and pluggable electrical contacts and receptacles. It also brings the transceiver electronics much closer to the main PCB for improved signal bandwidth and reduced noise.
Summing all of this up…
Transceivers are available in many different sizes, shapes and “flavors” such as formats, bandwidths and connector types. The best selection for a particular application will depend on the equipment that a transceiver is attached to and current and future network performance requirements. It is important to make sure that the selected transceivers are properly coded and pretested, up front, to confirm correct functionality with the related switch gear.
See you next time with another CTD down the road.
References and further reading:
1 Leave it to Transceivers,
Legrand Data Communications Division “Connecting the Dots”, 4-13-2016
2 Boosting Fiber Optic Links
, Legrand Data Communications Division “Connecting the Dots”, 4-27-2016
3 SWDM and WBMMF’s True Colors
, Legrand Data Communications Division “Connecting the Dots”, 6-11-2016