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Inspired by this slide, I became curious to know the (theoretical) latency of the latest WiFi standard. However Google didn't help. This ppt's 8th slide, compares latency of 802.3 (3000 microsecs) with that of 802.3ae (190 microsecs).

kamalbanga
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  • Have you checked the official 802.11 IEEE specification document? – Ramhound Nov 24 '14 at 12:15
  • [This](http://www.cisco.com/c/en/us/products/collateral/wireless/aironet-3600-series/white_paper_c11-713103.html) document has no info about latency. – kamalbanga Nov 24 '14 at 12:22
  • The fact it is not in the specification indicates to me that its either not important enough or they have not made it a specification for some reason. I am not sure how anyone is suppose to know something that isn't specified by the 802.11 standard. – Ramhound Nov 24 '14 at 12:33
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    It might not be important enough, but it's still a valid question, right? – kamalbanga Nov 24 '14 at 13:19
  • There might not be an answer. Engineering is pretty specific, anything not in the specifications, is normally not documented for a reason. – Ramhound Nov 24 '14 at 13:34
  • That's what I am saying - it might not be documented but maybe someone has run some benchmarks and has some approximate answer to this ques. I just want to know how much latency has increased from 190 microseconds. – kamalbanga Nov 24 '14 at 13:40

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In wifi, latency varies dramatically with load. 802.11 is a half-duplex medium (only one user can transmit at a time on a given channel), so as more users transmit, it's more likely that you will have to wait for a time slot. Thus there can be nospecific latency, just as there can be no specific per-user throughput.

Mel Beckman
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  • This gets even worse when you consider interference from other networks using the same (or overlapping) channels, and non-Wifi devices (security cameras, baby monitors, bluetooth, etc). – BowlesCR May 20 '15 at 00:14