Reply to post: Re: Optical Networking?

Intel adopts 40Gb per SECOND USB-C plug for Thunderbolt 3.0

Cynic_999 Silver badge

Re: Optical Networking?


Fibre has some advantages, not least of which is massively increased range compared to copper. However the one problem it always has is latency, because at the end of the day the devices at each end have to convert photons on fibre to electrons on copper, and that's always going to take time not necessarily huge amounts but why bother unless you really need to.


There is no significant latency converting between electrical signals & light signals. If you think about it you will realise that there cannot be, because neither the photo-transmitter nor the photoreceptor can "store" more than 1 bit, and so they must both convert between light and electrical signals within 0.5 bit-time at most. There is far more than a bit-time of latency involved in the system as a whole whatever the transmission medium, because each byte (or more usually word) that is sent must be serialised and then de-serialised before it will be passed to and hence be processed by the destination CPU.

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Biting the hand that feeds IT © 1998–2021