I haven't used hwsim with hostapd yet, but I'm pretty sure, that it is possible to change the beacon rate (as we changed them in 802.11s Mesh Mode). I'm think the problem here is, that you can't assign a HT rate for beacons, because action/management frames are always sent with base-rate or at least they need to be sent with legacy-rates in mixed mode. I'm not sure, whether hwsim can use the "green-field" mode, in which everything is sent with ht-rates, but most drivers for real devices do not support green-field mode. So the highest beacon rate seems to be 54.0 mbit/s. Nonetheless, hwsim do not simulate the real timing behavior of this rates. Since hostapd is only responsible for the association protocol but not data transmission, it should not decrease the seen rates extremely, but I have no numbers for it. As more effort you use to simulated the on air behavior, you decrease the throughput rates. kind regards Benjamin Am 22.11.2018 um 13:18 schrieb Ramon Fontes: > I've tested the same setup with adhoc and the throughput seems to be > higher as expected. Thus, the problem comes up when I use hostapd. > > I noticed that the maximum supported rate by hostapd (legacy) is 54Mbps. > Extended supported rates: 24.0 36.0 48.0 54.0 > > Then I tried to modify mac80211_hwsim in order to provide more rates > and it didn't work: > Extended supported rates: 24.0 36.0 48.0 54.0 54.0 54.0 54.0 > > The maximum supported rate is always 54Mbps. > > Then I found the Beacon frame TX rate configuration from hostapd.conf. > After trying to enable the beacon rate (e.g. beacon_rate=ht:1) I got > the following msg: > ap1-wlan1: interface state UNINITIALIZED->HT_SCAN > Using interface ap1-wlan1 with hwaddr 02:00:00:00:02:00 and ssid "ssid-ap1" > nl80211: Driver does not support setting Beacon frame rate (HT) > > and hostapd doesn't work. > > Could this problem be related to mac80211_hwsim? > > Em qua, 21 de nov de 2018 às 10:09, Ramon Fontes > <ramonreisfontes@xxxxxxxxx> escreveu: >> Yes. I thought that it could be related to the number of antennas (or >> something else) after seeing this result >> (https://bobcopeland.com/blog/2014/09/wmediumd-speed-test/) provided >> by wmediumd. >> Em qua, 21 de nov de 2018 às 09:48, Johannes Berg >> <johannes@xxxxxxxxxxxxxxxx> escreveu: >>> On Wed, 2018-11-21 at 09:47 -0300, Ramon Fontes wrote: >>>> Okay! Thanks a lot. >>>> >>>> Indeed, the maximum throughput when using only hwsim is in the order of Gbp/s. >>> So I guess the question is where it's going wrong - is it the wmediumd >>> overhead (netlink), some air simulation in wmediumd, etc. >>> >>> johannes >>> -- M.Sc. Benjamin Beichler Universität Rostock, Fakultät für Informatik und Elektrotechnik Institut für Angewandte Mikroelektronik und Datentechnik University of Rostock, Department of CS and EE Institute of Applied Microelectronics and CE Richard-Wagner-Straße 31 18119 Rostock Deutschland/Germany phone: +49 (0) 381 498 - 7278 email: Benjamin.Beichler@xxxxxxxxxxxxxx www: http://www.imd.uni-rostock.de/
