[Babel-users] Wifi-Opp [was: Still no ad-hoc in Android 4.0 "Ice Cream Sandwich"?]

[Juliusz Chroboczek]

> We have proposed an alternative to WiFi Ad Hoc called WiFi-Opp, which
> is more flexible and doesn't require pairing (as in WiFi Direct which
> we tested on Galaxy SII).

Very interesting work, although I'm not sure it's an alternative to
ad-hoc.

The tl;dr version: they're running in infrastructure mode, and randomly
switching between AP and STA.  There's a number of heuristics involved,
but they appear to have refined their algorithms to the point where they
claim to run a naive flooding protocol at 70% of the performance of
ad-hoc mode, with 20% of the power usage.

Unless I'm missing something, WiFi-Opp doesn't allow quickly scanning
for all the peers in range (which can be done with just a few multicast
packets in ad-hoc), or communicating with multiple peers in quick suc-
cession (which makes it unsuitable for something like a DHT algorithm,
let alone a mesh network).  That's why I'm not so sure about the claim
to being an "alternative" to Ad-Hoc.

I was also under the impression that the iPhone supports ad-hoc mode out
of the box, but the paper claims otherwise.

Franck, could you please clarify two things?  First, you claim
a five-fold decrease in power usage w.r.t. ad-hoc, but was that measured
with WiFi or with Bluetooth?  And second, when you speak of "percentage
of the dissemination performance", what is it exactly you're measuring?

Thanks for the interesting read,

-- Juliusz