Talk:Data communication

Asynch vs. synch

The asynchronous versus synchronous communication discussion seems misdleading --- it talks about special cases of general ideas as if they are the only cases. Asynchronous communication is not necessarily controlled by start and stop bits, and the section is written as though all asynch comm. is 8 bit serial. The comments on clock skew in the synchronous comm discussion are also misleading as not all --- in fact, little --- synchronous communication suffers from skew-related data corruption. I would fix this myself except that I tend to be too wordy for short sections. Zack112358 (talk) 05:53, 11 April 2010 (UTC)

I have trimmed this back. The section references Comparison of synchronous and asynchronous signalling so hopefully that's not too messed up. ~Kvng (talk) 23:20, 4 November 2018 (UTC)

Proposed merging

The data transfer article appears to be a nearly identical topic. I propose merging with this article if there are no major objections. JonHarder 19:38, 25 January 2006 (UTC)

Support but both articles are appallingly sketchy! --Wtshymanski 01:35, 26 January 2006 (UTC)

Done.

maximum speed

Can anybody tell me that What is the maximum speed of data transfer can be supported by copper?

not the speed of light.

Do you mean the minimum rise time for a digital bit to transmit across a copper wire, or the maximum number of bits you can get through in a given amount of time?HatlessAtless (talk) 19:31, 18 July 2008 (UTC)

typo

However this method ohg, as there is more interference between many wires than between one.

Could somebody please tell me what ohg is meant to mean?

It came from edit http://en.wikipedia.org/w/index.php?title=Data_transmission&diff=84946893&oldid=84621944 .

I can't figure it out either, so I'm reverting that sentence.

Fixed. --76.209.28.72 00:49, 15 June 2007 (UTC)

How is clock encoded into synchronous transmissions?What is DPLL? —Preceding unsigned comment added by 59.93.23.139 (talk) 10:52, 19 November 2007 (UTC)

I have removed the part about interference on parallel data transmission as it isn't very accurate and have replaced it with a more accurate substitute (skewing) which is what i believe the original author was trying to explain but didn't know the correct terminology. dc141 20:09, 3 December 2007 (UTC)

Oppose merge to Digital communications

I oppose the merge to the Digital communications. Data can be transmitted by analog means as well as digital. Data is not synonymous with digital. Oicumayberight (talk) 20:02, 27 August 2008 (UTC)

I also oppose the merge to Digital communications; I agree with the previous post but there are more reasons to oppose this merge. There are three types of information that we communicate: data, voice, and video. Long distance voice communications were taking advantage of the conversion from analog to digital (definitely in the realm of digital communications) when data communications (between computers) was still in its infancy. Furthermore, "transmission" is only one piece of "communications". The OSI seven layer model illustrates this, as only the lower four layers of the model relate to transmission. The upper three layers (making sure the formatting is compatible, that the sender is allowed to send to the receiver, etc.) are just as essential to successful communication as is the transmission portion. Both the "data" and the "transmission" halves of "data transmission" are subsets of digital communications. Techgeek830 (talk) 12:02, 30 August 2008 (UTC)

Does the first post imply that Digital communications does not involve Digital modulation methods (i.e. digital communication over analog media)? That is wrong. Mange01 (talk) 22:16, 21 October 2008 (UTC)

NO. I don't know how you drew the conclusion that I was excluding anything with an inclusive statement. Data transmission is not dependent on digital but can include digital. Oicumayberight (talk) 23:28, 21 October 2008 (UTC)

Arguments for a merge: A text book on data transmission and one on digital communication typically involves the same chapters, including multiple access, error control, digital modulation, line coding, data compression, cryptography etc. So both includes layer 6 - the presentation layer. None of them would include routing, process-to-process communication, etc (layer 3, 4 and 5), which would be covered in a book on "data communication" or "computer networks". Anyway, even if there is no support of a merge, the relation between these topics should be clarified in the article. Mange01 (talk) 22:16, 21 October 2008 (UTC)

To say that data transmission is digital implies that there is no such thing as analog data transmission. That would be misleading. Oicumayberight (talk) 23:28, 21 October 2008 (UTC)

A better solution?

The problem here is not what is or isn't covered by a text book in the field, but with oversimplification of the words in the English language. "Data" may refer to digital data most often, but is not used exclusively to describe digital data. Considering that these articles are often translated in other languages, perhaps a better solution is to make this an overview article or a disambiguation page branching to two separate articles titled: Data transmission (analog) and Data transmission (digital).

Passband and baseband data transmission (=passband and baseband digital transmission) are more common terms. Mange01 (talk) 21:30, 2 April 2009 (UTC)

Information Transmission

I oppose merging Information Transmission with Data Transmission. First, Data is not necessarily Information. Data is a very specific form of information, sans context. Information transmission has a wider context than is presented in this entry. Information Transmission relates to a wider social context than this entry implies. Data Transmission could me a Narrower form of Information Transmission. But Data Transmission is not the same as Information Transmission. —Preceding unsigned comment added by 129.128.81.74 (talk) 04:01, 14 November 2008 (UTC)

It appears that it's a redirect and not a merge request. Was there an article for Information Transmission that was deleted? Perhaps a disambiguation page is needed. But without an article for Information Transmission, I don't know what it would point to.

Data is actually broader in scope than information. All information is data, but not all data is information. Unless you are using the narrower scope of data which erroneously narrows the scope to digital data. Oicumayberight (talk) 04:13, 14 November 2008 (UTC)

Klystron

Is the Klystron also not a form of wireless data transfer device/method —Preceding unsigned comment added by 91.182.161.238 (talk) 10:42, 5 February 2010 (UTC)

the main major betwen asynchronous and synchronous be the converter factor from analoge

‡Signal Over Time

• For the two digital signals below decide if these signals synchronous or Asynchronous, and explain why in details. —Preceding unsigned comment added by 87.236.233.183 (talk) 11:23, 18 February 2010 (UTC)

External link is broken

The External link to http://halowave.webs.com/ is broken. I do not know if I should only remove the broken link or the section heading 'External links' as well... — Preceding unsigned comment added by FrankvD NL (talk • contribs) 20:11, 3 October 2014 (UTC)

Data copying

I removed the following text (added 31 July 2015) from the lead:

Because of the perfect reproducibility of digital data (lossless compression, nearly error-free communication), a data transfer to any kind storage device, be it permanent such as a hard disk or temporary as RAM, is the basis of data copying or data duplication in the computer age. Moving data is always a combination of a data transmission with data deletion on the sender side.

Per WP:LEAD, the lead should be a summary of what is in the article. More importantly, the text is an observation that storing data involves data transmission, and that does not explain anything about the topic of this article. Johnuniq (talk) 00:09, 21 November 2015 (UTC)

Unfortunately, you got it wrong. Read again: Storage is not the point (although, of course, it would be nice not to have your data vanish in a black hole at the end of the channel,right?). My passage is about data copying or moving. Data transmission either local or remote is at the heart of copy operations (or how would you go about it?). It appears crucial to me to make that point somewhere. -- Kku 07:56, 14 January 2016 (UTC)

It's true that data copying/moving involves data transmission, but that observation does not seem useful in this article, particularly in the lead. Let's see if anyone else wants to comment. Johnuniq (talk) 09:43, 14 January 2016 (UTC)

In-band and out-of-band control

• In-band control (edit | talk | history | links | watch | logs)
• Out-of-band control (edit | talk | history | links | watch | logs)

Does any merit exist to keep these two unsourced stubs separately of the main topic? Incnis Mrsi (talk) 11:03, 21 October 2019 (UTC)

Are you suggesting both topics should be covered in Data transmission? I'm not sure I support that. ~Kvng (talk) 13:33, 24 October 2019 (UTC)

@Kvng: alternatives? Incnis Mrsi (talk) 15:10, 24 October 2019 (UTC)

There's no problem leaving it as it is. Options may be clearer if improvements are made to the stubs. I think the stubs have merit. ~Kvng (talk) 15:26, 24 October 2019 (UTC)

Article scope and title

Fgnievinski has broadened the stated scope in the lead to include data communication and data reception. Data communication already redirects here and I can't identify a better place to send it. There is no Data reception redirect or article and perhaps there should be. If we're going to broaden the scope like this, I think we need to consider moving the whole article to Data communication. ~Kvng (talk) 14:40, 25 September 2020 (UTC)

Agreed; there ain't transmission without reception implied, hence communication; I can do the renaming if no one objects. 15:43, 25 September 2020 (UTC)

data communication

is that true when two peoples are talking to each other in a room then the transmission medium between through Air ? Sheikh muhammad shariq ashrafi (talk) 22:13, 16 January 2022 (UTC)

Yes, unless they're lip reading. ~Kvng (talk) 17:27, 20 January 2022 (UTC)

Lead

The article opens with "digital communication", but data communication is not necessarily digital; as people also communicate with analog or organic methods. I feel if the purpose of this article is to discuss digital communication, maybe the title could be moved to "digital data communication", or the article could be expanded to focus on not just digital communications? 2A00:23C4:41A:9601:82C:F5C4:ABF7:DF82 (talk) 15:45, 16 April 2022 (UTC)

Thinking too, in that context the word "information" can better apply, but "data" in isolation is still ambiguous. 2A00:23C4:41A:9601:82C:F5C4:ABF7:DF82 (talk) 15:49, 16 April 2022 (UTC)

Proposed addition to Applications and History

During and after WWII digital technology became a key subject for research e.g. for radar, missile and gun fire control and encryption. In the 1950’s scientists were trying various methods around the world to reduce errors in transmissions using code and to synchronise the received data. The problem being transmission noise, time delay and accuracy of received data. In 1949 the mathematician [Claude E Shannon] published an article [A mathematical Theory of Communication] which laid out the basic elements of communication. In it he discusses the problems of noise.

Shannon realised that “communication signals must be treated in isolation from the meaning of the messages that they transmit” and laid down the theoretical foundations for digital circuits. “The problem of communication was primarily viewed as a deterministic signal-reconstruction problem: how to transform a received signal, distorted by the physical medium, to reconstruct the original as accurately as possible”. (Ref: Quanta Magazine, How Claude Shannon invented the future).

https://www.quantamagazine.org/how-claude-shannons-information-theory-invented-the-future-20201222/

In 1953 RH Barker published a paper demonstrating how this problem to synchronise the data in transmissions could be overcome. The process is described in “Group Synchronisation of Binary Digital Systems”. When used in data transmissions the receiver can read and if necessary correct the data to be error free by auto and cross correlation i.e. by achieving zero autocorrelation except at the incidence position using specific codes. The Barker sequence utilised a technique of auto correlation and cross correlation which at the time produced great interest as his method solved the problem, initiating a huge leap forward in telecommunications. The process has remained at the forefront of data transmission and telemetry.

“In a pioneering examination of group synchronization of binary digital systems, Barker reasoned it would be desirable to start with an autocorrelation function having very low sidelobes. The governing code pattern, he insisted, could be unambiguously recognized by the detector. To assure this premise, Barker contended the selected pattern should be sufficiently unlikely to occur by chance, in a random series of noise generated bits” (1.)p13

The principle of using phase shifted codes with auto and crosscorrelation to achieve synchronisation has since been developed into many more hybrid formats with a variety of names such as Nested Barker codes, Polyphase Barker codes, Barker word, Barker like sequences, Barker convolution codes, Quadraphase Barker codes, Double or nested Barker codes (use the Kronecker product of two Barker Codes), Compound Barker codes etc. Some variants being named otherwise by their inventors. These all use the same principle of good autocorrelation with minimum amplitude of side lobes. Each variant being designed to meet specific applications.

RH Barker solved the problem with is ground breaking invention. Barker sequences are used in most digital applications today. These include, radar, near space telemetry, GPS, mobile phone technology, ultrasound and thermography, sonar, LAN technology, DSSS, QPSK, and HSSS, RFID – vehicle, goods and livestock tracking, bar code scanners, inventory management, vehicle, parcel, asset and equipment tracking, inventory control, cargo and supply chain logistics etc. etc.

The invention of Barker code together with the use of auto correlation and cross correlation was a major breakthrough and should be recognised as being of historical significance to data transmission. This was in the days of valves, relays, oscilloscopes, soldering irons and Avo meters.

For the reasons given above R H Barker should be acknowledged for inventing a pioneering method to solve a problem.

I would therefore like to add the following to the ‘Applications and history’ section of this article. After the second sentence ending 1951. Add The first practical method to overcome the problem of receiving data accurately by the receiver using digital code was invented by [Ronald Hugh Barker] in 1952, published in 1953. Windswept (talk) 14:52, 28 July 2022 (UTC)

The first three paragraphs look good. The rest of it gets a bit WP:UNDUE on Barker codes and has some WP:PEACOCK issues though it could be useful in improving Barker code. ~Kvng (talk) 14:53, 1 August 2022 (UTC)

Just to clarify all I am suggesting is that a single sentence is added to the Applications and History Section after the second sentence in the second paragraph i.e. after 1951 for the reasons given.

The sentence being as follows:- "The first practical method to overcome the problem of receiving data accurately by the receiver using digital code was invented by [Ronald Hugh Barker] in 1952, published in 1953".

If you are in agreement please add it in. Windswept (talk) 14:42, 2 August 2022 (UTC)

That seems reasonable but it would be optimal if we had a WP:SECONDARY source that supported this statement. Neither of the two sources you've linked to are all that. ~Kvng (talk) 13:49, 5 August 2022 (UTC)

Some casual reading on history here

• https://www.quora.com/What-is-the-history-behind-data-communication

Whizz40 (talk) 13:54, 13 November 2023 (UTC)

References