Talk:IEEE 802.11

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14th channel[edit]

Article currently says "The 2.4 GHz band is divided into 13 channels spaced 5 MHz apart, beginning with channel 1 centered on 2.412 GHz. A 14th channel was briefly proposed in Japan, but later dropped.[citation needed]"

However the 2007 and 2012 rollups both reference channel 14 in the channel maps (search for '2484' -- its frequency). I'm rewording this section to make it clear that the channel exists but is limited to certain regulatory domains.

Teslacuted (talk) 01:41, 16 July 2013 (UTC)

802.11-2012[edit]

The Standard or amendment? subsection of the Standard and amendments section seems to have been missed when updating the article with respect to 802.11-2012 — ~Bin~talk 09:36, 19 April 2012 (UTC)

Agreed. There is more information on the new IEEE 802.11ae-2012 standard on the IEEE website: https://standards.ieee.org/findstds/standard/802.11ae-2012.html 10:38, 7 May 2012 — Preceding unsigned comment added by 50.15.136.118 (talk)

Colleagues. I have reviewed the new 802.11-2012 standard (IEEE released it to the 'GET' program just yesterday). There are so many new additions (and changes), that I believe it deserves it's own article -- so I created an initial draft. If you care to review and/or expand upon it, please examine it here: http://en.wikipedia.org/wiki/Wikipedia_talk:Articles_for_creation/IEEE_802.11-2012 — Preceding unsigned comment added by Paul.j.richardson (talkcontribs) 16:49, 2 October 2012 (UTC)

Looks like a good start to me. ---fudoreaper (talk) 07:34, 4 October 2012 (UTC)

In Standard and amendments you find a lot of 802.11 protocols, in section Protocols only the main protocols a,b,g,n and new for me 802.11-2007. I like the table in Protocols, so is it possible to merge this two sections?194.113.154.132 (talk) 14:52, 1 October 2013 (UTC) br

I don't understand why this very important start on an article is being rejected by Wikipedia. Does Wikipedia no longer allow stubs? If so that seems like a very bad move by Wikipedia. Vaughan Pratt (talk) 00:20, 22 August 2014 (UTC)

Hobgoblin of little minds[edit]

This page says clearly:

802.11g was based on OFDM modulation and utilized a channel bandwidth of 20 MHz. This occasionally leads to the belief that four "non-overlapping" channels (1, 5, 9 and 13) exist under 802.11g, although this is not the case.

And the diagram:

Spectral masks for 802.11g channels 1 – 14 in the 2.4 GHz band

seems to show the non-overlapping channels as 1,6 and 11, like 802.11b

But the diagram:

NonOverlappingChannels2.4GHzWLAN-en.svg

which is also included shows the non-overlapping channels for 802.11g/n as 1,5,9 and 13, in direct contradiction of the article.

So, what is it? HughesJohn (talk) 12:46, 11 August 2013 (UTC)


According to the 2007 revision, in section '19.5.2 Adjacent channel rejection' "Adjacent channels at 2.4 GHz are defined to be at ± 25 MHz spacing.".
My reading of this is that even though this was originally based around 22MHz carriers when using CCK, the OFDM modulation reused the spacings without redefining them, which I imagine would have required a full channel->frequency reassignment. So, as the centre frequencies of the OFDM carriers are at the same frequency as a CCK carrier, they are still technically adjacent to each other, even though their nodes fall off faster than a CCK carrier. Technically adjacent, therefore technically no change to the non-overlapping channels. However I imagine that if OFDM only operation could be guaranteed the 1,5,9,13 scheme could be considered valid, but since the rate selection is automatic, a station can dynamically switch to CCK (or worse, Barker) if its SNR is too low, which means you can't really, practically, ever guarantee OFDM only operation. This means the red-on-white diagram is technically correct (the best kind of correct) but it doesn't make it clear that the same network may be using multiple modulation rates at the same time. Management frames, in particular, are often sent at an older modulation, even in good SNR environs.
This is of course, all wild speculation and should be treated as such. Teslacuted (talk) 19:49, 11 August 2013 (UTC)

I don't understand "This occasionally leads to the belief that four "non-overlapping" channels (1, 5, 9 and 13) exist under 802.11g, although this is not the case.". Why are they overlapping? The PSD shape is 18 MHz wide and drops at the edge in 2 MHz by 20 dB. — Preceding unsigned comment added by 135.245.192.4 (talk) 15:56, 6 November 2013 (UTC)

Article does not meet Wiki standards[edit]

Wireless N redirects here. About.com says: "Answer: Wireless N is a name for hardware gadgets that support 802.11n Wi-Fi wireless networking."

This article seems too technical and full of jargon, which is another way of saying it's poorly written. Wiki guidelines require that articles be accessible to the average user (IMO; at least in the lead section). Duh. It describes a bunch of rules but does not explain what the hardware gadgets do, what such a device is called, what purpose these devices serve, etc. The Big Picture. Suggest looking at some other sources such as perhaps: What Is Wireless N? or youtube's Wireless G vs N explained for suggestions to better explanations. See also: Wikipedia:Manual of Style (lead section).
  Please remember that a list of facts is not an explanation. A list of parts does not describe a car nor any other system. Thanks.
--108.252.225.238 (talk) 04:07, 17 July 2014 (UTC)Doug Bashford

This article covers the facts in much more details than the blather in sales brochures. As a reasonably educated person I generally prefer details to oversimplification. It explains not only Wireless a, b, g, n and ac, but also the lesser known letters used, as well as the bigger picture and some issues that real world people have to deal with to use the related "gadgets". Please keep this article as a detailed overview of the whole 802.11 standard family, don't dumb it down to beautifully written sweet nonsense. If I look up Elephants I also expect something much more detailed and precise than "huge gray animal with very long nose that it can move like an arm and two very long white teeth". Jbohmdk (talk) 01:47, 13 September 2014 (UTC)

More confusion in the paragraphs about channel separation[edit]

The 3 paragraphs about channel separation, which begins with "Confusion often arises..." seem to be confused themselves. Most notably I see two issues in the current text, but am not sure how to fix it, as I do not know the facts well enough. The two issues are:

  • There is an unfortunate conflation of the rules for assigning channels to multiple (cooperating, roaming) access points (cells) of a single large network/SSID and the (different) rules for assigning channels to multiple networks/SSIDs where the access points don't talk to each other, but the (human) owners try to minimize mutual interference. Similarly, there is some conflation between what happens if you line up all the conflicting access points on a small table in the middle of the house and what happens when each access point is in a different home/office in a large crowded building. The Villegas source discusses these distinctions, but with little detail.
  • A Cisco article about the inadvisability of using 15MHz channel separation for multi-cell networks in the US 11-channel regdomain is used as the sole source for a claim that 20MHz channel separation is problematic in the EU 13-channel regdomain, while a research article that used spectrum analyzers to scientifically investigate how much channel separation is really needed is used as the sole source for a claim that such high end equipment is needed to decide if 20MHz separation is good enough for each real world situation. That badly sourced paragraph contains important information which should be given (after adjusting for factual correctness), so it cannot simply be deleted, but it needs to be fact checked then the facts need to be properly sourced. Jbohmdk (talk) 01:26, 13 September 2014 (UTC)