From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.toke.dk (mail.toke.dk [52.28.52.200]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 4D7403B2A3 for ; Mon, 10 Apr 2017 09:30:03 -0400 (EDT) From: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=toke.dk; s=20161023; t=1491831001; bh=k6/aRHcbCsc+e5/MR1j9qJfxWbyspAKFJQM0sXWx1DA=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=P6WhBUS0jUOb0l41jTw/Xi+QF3M1JQJkPhPQbm3dRlTBWisWN9hXhDrjcpubHjD// 2JJn1svG4ATnB288ZDZhfLhb6u+KGldyvdN/QM2xPPt+yG7g07m8X+dqcPr230ZEtA sq6Ajk1o7APB8WNN2kvQNIsBUzkznqhN1WQRDa+Fxup3psO1kpqJ1wk9GjjxiiotBP E28GR052u0zq+TqkSLg9O47cxVBcSfLxAhKqKOU9UuovdBggb1Sx299TgMsf+LB7Ym rA6Ns6eKSOv4I8raOHX0c0rRyCLK9DrmEvqx+w2h90G1eea86XuYxbcNANcio9cgRw xCmJdmuyRJBsg== To: Pasquale Imputato Cc: mab-wifi@lists.bufferbloat.net References: <87h92ytiik.fsf@alrua-karlstad> Date: Mon, 10 Apr 2017 15:29:59 +0200 In-Reply-To: (Pasquale Imputato's message of "Wed, 5 Apr 2017 15:47:19 +0200") X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <877f2smluw.fsf@alrua-kau> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [mab-wifi] Possible contribution X-BeenThere: mab-wifi@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Multi-armed-bandit WiFi rate control List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Apr 2017 13:30:03 -0000 Pasquale Imputato writes: > Hi Toke, > > sorry for the long delay. > > In ns-3 the 802.11 standard is implemented rather accurately. > The simulator models the standards 802.11a/b/g/n/ac, an initial draft of ax and the e emendament for the QoS support. > The models support MIMO in 802.11n/ac/ax. > The example 802-11n-mimo in examples/wireless provide and overview of the MCS and MIMO capabilities by exploring for each HT MCS from 1 to 4 MIMO streams. > > Multiple rate control algorithms are implemented in the simulator. Some of them are found on real devices, while much others are only available in literature. There is implemented the minstreal HT algorithm, that could be useful for benchmark. > The rate control algorithms are modelled by the WiFiRemoteStationManager class of the wifi module. The class hold a list of per-station-state info modelled after the struct sta_info in Linux kernel. > Create a new rate control algorithm can be done by introducing a new child class of the WiFiRemoteStationManager class in the wifi module of the simulator. > > The simulator capabilities seem to fit our needs in term of MCS and > MIMO. Yeah, this sounds great! Looking at the WiFiRemoteStationManager code, there's an "IsLowLatency" property which indicates that the model can make decisions for every packet. If this is *not* set, how does a model then make decisions? And is there a concept "retry chains" for the rate selection algorithm (where a sequence of rates to try are picked at once when a decision is made)? > Since we are in an exploration phase, how we can contribute to the > exploration? I think the two main things we are trying to figure out are the correlations between different rates. Which involves answering questions like: 1. What correlations exist between the success probabilities of sending at different rates. I.e., can we always assume that if a transmission fails at a low rate (more robust encoding), it would also have failed at a higher rate (or conversely, if it succeeds at a high rate, it would also have succeeded at the lower rate). Does this hold within the same MIMO configuration? What about between different MIMO configurations? 2. How does rate influence collision probability in the presence of several nodes? I.e., if we send the same transmission size at a lower rate, it is going to take longer to send; does this affect the probability of collision with other nodes? If it does, how pronounced is this effect? 3. How does transmission (aggregation) size affect the success probability of transmitting at a certain rate? Another thing that could be useful is producing some test data sets (of "ground truth") that we can use for evaluating algorithms on. For instance, given a static scenario of N clients connected to an access point, produce a data set which contains the steady state success probabilities for each rate (for each node). And another data set which introduces mobility (at a credible rate) and makes the rates a function of time. Does any of the above sound doable? :) -Toke