full and half duplex


Thread Starter

Abdal Hakam

Hi List is full duplex necessary for metering ? what I think is half duplex is enough is this, and if full is a must how it can be achieved using fibre optics we have only two fibres available . thank you all.


We need a lot more info to address the first question. Such as: What are you metering? What is your rate of change? What are your accuracy requirements and flow rates? What bit rate are you using? etc. etc. etc. As far as full duplex using 2 fibres, that is all you should need for full duplex fibre optic. One fibre is used as a transmit, and the other is the receive. They are obviously reversed on the opposite end, such that if fibre 1 is transmit at 1 end, it is receive on the other. Same for the other fibre. In the end, it depends on what you are using to convert the signals from electrical to optical as to whether you need half or full duplex. Some transceivers will work with half and others will require full. If you already have the transceivers, look in the spec sheet. Otherwise, spec a transceiver that will do what you need based on the application. More details on the application will get you some advice on what you may need. --Joe Jansen

Darold Woodward

You have not provided enough detail to answer your question. What kind of metering? What kind of performance are you looking for? What protocol are you using? Two fibers is sufficient for a full duplex communication channel (one fiber each direction, simultaneous). Your end equipment may not even support it though. Darold Woodward PE SEL Inc. [email protected]

David Bergeron

Two fibers are all that is needed for full duplex. One fiber transmits data in one while the other fiber transmits data in the other direction at the same time.

Abd Al Hakam

Thank you a lot for responding, I am attaching a brief description for our application, and I appreciate if you can send to me (By e-mail)any specification documents for a Similar application as a guide line for specifying the required system. some of the points have not ben finalized yet e.g. communication protocol and rate of change thanks for any suggestions.