Talk:Duplex (telecommunications)

Semi-Duplex Missing?
Why is the popular Semi-Duplex missing in this article? — Preceding unsigned comment added by 108.183.84.89 (talk) 02:41, 8 August 2013 (UTC)


 * Semiduplex is redirected here mentioned in the lead as a synonym for half-duplex. I'd create a Semi-duplex but there are no incoming links here through Semiduplex and this is the first time I'm hearing this term so I'm not sure how loved it is. ~Kvng (talk) 19:28, 12 December 2022 (UTC)

Silly half-duplex analogy
From the article: "A good analogy for a half-duplex system would be a one-lane road with traffic controllers at each end, such as a two-lane bridge under re-construction. Traffic can flow in both directions, but only one direction at a time, regulated by the traffic controllers."

The boldface part works fine as an analogy, no problems there. The bold-italic part doesn't track with the nature of half-duplex systems, because there is no external 'regulator' akin to traffic controllers when using half-duplex systems (at least in the few obvious examples that come to mind) - when using walkie talkies, the users themselves must manage the exchange of transmissions, analogous to road traffic (for example by ending their transmission with 'over') and likewise on the one-land road cars would just wave to each other to indicate intentions (I can't speak for the everywhere, but in England, Wales, Scotland and France (much of rural, hilly parts of Europe) I can say there are definitively one-lane, two-way roads, without traffic co-ordinators or traffic lights, and drivers must negotiate these roads themselves - they are usually short, quiet roads, and in the event two cars meet in opposite directions, the car closest to the end of the road simply acknowledges the other car and backs up).

Upon reaching the italic part of the analogy it just becomes absurd; I am sure readers with even the most basic level of education can envisage a one-lane road with two-way traffic without having to bring into the analogy a bridge and some re-construction work - even if you live in a region without such roads and have never travelled anywhere with one. To reduce it to the absurd, the bridge inclusion adds as much to the analogy as would the following "...such as a two-lane 17th century cable-stayed bridge under re-construction due to corrosion caused by decreasing pH levels in local precipitation as a result of climate change from government-backed deforestation for the purpose of clearing land for increased soybean production in order to meet the growing global economic demand." - it's entirely superfluous.

I would like to edit it, so that it reads "A good analogy for a half-duplex system would be a one-lane road that allows two way traffic, traffic can only flow in one direction at a time." or if absolutely necessary, "A good analogy for a half-duplex system would be a one-lane road with traffic-lights allowing two way traffic, traffic can only flow in one direction at a time - when the light is green at one end it is red at the other."

The reason I exposited this here instead of just making this trivial edit is that I am sure it would either be flagged as vandalism or somebody would complain without understanding my reasoning, because I happen to choose to edit anonymously from an often changing IP (having no desire to have every edit I ever make collated and searchable). I'm also rather bored so I thought I might as well. ''So I will check back in a few days and if nobody has complained I will make the edit then. If anybody reverts it after that, I will put the change back, and direct them here to explain why they reverted it and to wait until consensus is reached before further edits are made, as a full explanation and opportunity to object was given prior to the edit and in good time.'' 86.8.54.48 (talk) 00:46, 24 September 2015 (UTC)


 * I have implemented this suggestion. Different half-duplex systems manage the channel in different ways so it makes sense to remove discussion of traffic controllers. ~Kvng (talk) 19:28, 12 December 2022 (UTC)

Merge from Simplex communication
This is a synonym for Half duplex which is a redirect to this article. ~Kvng (talk) 15:44, 3 March 2023 (UTC)
 * Support merge Joyous! Noise! 05:14, 5 March 2023 (UTC)
 * Support merge with redirect, I am not convinced that they are true synonyms, but both are aspects of the same topic, neither are large. Simplex can be used to describe one-way only traffic, while half-duplex requires the possibility of two-way (as I understand it - more citations may be needed). It makes sense to describe and compare them at the same place. &middot; &middot; &middot; Peter Southwood (talk): 05:02, 20 June 2023 (UTC)
 * ✅ Klbrain (talk) 10:55, 26 November 2023 (UTC)

Dual simplex versus full duplex
This distinction is not at all clear -- unless the phrase "both variants are commonly referred to as full duplex" is a hint that nobody really cares about the difference, and that this article will also use them interchangeably. Is that the intent?

For example, this article says "Many Ethernet connections achieve full-duplex operation by making simultaneous use of two physical twisted pairs inside the same jacket", but having two sets of wires sounds like the literal description of "dual simplex".

Then it says "Other Ethernet variants, such as 1000BASE-T use the same channels in each direction simultaneously", which isn't really true: only one side talks at a time, and they use collision detection to re-transmit when needed. That sounds exactly like "half duplex" to me.

Is there any true full duplex communication channel? This page suggests that the distinction is that "dual simplex" is an architecture, while "full duplex" is a characteristic of a system. 2601:602:A080:1240:DEE9:BFD4:96A8:9200 (talk) 12:35, 22 June 2024 (UTC)


 * Practically, there's no difference – that's why most people don't bother making one. Technically, dual simplex uses one simplex channel for each direction (e.g. 10BASE-TX, 1000BASE-SX) while full duplex uses a single channel bidirectionally (e.g. telephone, 1000BASE-T, 10GBASE-T). --Zac67 (talk) 17:15, 22 June 2024 (UTC)