[Cerowrt-devel] [Make-wifi-fast] more well funded attempts showing market demandfor better wifi

Dave Taht dave.taht at gmail.com
Mon Jun 27 13:55:31 EDT 2016


In terms of wifi history... since I go back to the 70s...

was that we did not know how to do it - 73 we had aloha, which begat
ethernet... and for years progress was slow. Even as late as 91 or so
a "good" microwave link cost something like 40k an end, and required
special cooling and permits on so on. Wifi was started as an ipx/spx
bridge tech that didn't start to get anywhere until the mid 90s.

It was far from obvious at any point that the cost reductions would
take place that did, there was so much work in the analog domain that
looked (at the time) resistant to moores law. As for spectrum, finding
ways to leverage 2.4ghz cost metricom's backers in particular more
money than I care to think about, and I'm always pointing at how the
discovery that a more centralized clock and a retransmit at the mac
layer is what eventually made 802.11b viable. Many other wireless
ideas have been tried and died - wimax, for example, UWB, for another.
Bluetooth has evolved into adding "discovery prototol", which was kind
of unexpected... (there is even 6lopan over bluetooth now). The 5ghz
spectrum users have tended to adopt their own mac, as has some other
less popular bands.

While I'm pretty happy that we've got much of the queuing theory for
fixing 802.11n and 802.1ac nailed now, outstanding problems include
the hidden station problem, the rise in the background noise levels,
insufficient channels, and increasingly proprietary standards and
chipsets, as well as transport, switching and routing protocols
layered on top originally designed for isochronus transports.

I like to think (or possibly delude myself), that the solutions to
airtime fairness scheduling now emerging may one day lead to saner
scheduling around the hidden station problem in particular. Otherwise,
and elsewhere, there remain a lot of rocks to bang together, and a
long list of other issues we've captured elsewhere.

I am still periodically reviewing and updating this as we go along, as
it remains the best central document we have on all that's wrong in
wifi with some hints as to how to go about fixing them.

https://docs.google.com/document/d/1Se36svYE1Uzpppe1HWnEyat_sAGghB3kE285LElJBW4/edit


More information about the Cerowrt-devel mailing list