Re: General VHT rate-ctrl question
On Wed, Apr 13, 2016 at 10:31 PM, Dave Tahtwrote: > > On Wed, Apr 13, 2016 at 6:18 AM, Ben Greear wrote: > > > > > > On 04/13/2016 01:01 AM, Johannes Berg wrote: > >> > >> On Tue, 2016-04-12 at 16:48 -0700, Ben Greear wrote: > >>> > >>> If a station and it's peer can both do VHT, is there ever a good > >>> reason to even try HT rates? > >>> > >> > >> Not really; perhaps if you could do HT greenfield preamble (which VHT > >> doesn't have) you could get something out of it, beyond that I don't > >> see a reason to try. > >> > >> Unless, for some strange reason, it supports only single stream VHT and > >> dual-stream HT or something really weird? > > > > > > I was wondering if there was ever a reason that, say 450Mbps HT > > would work better than MCS-1 for VHT. Or, maybe a mid-rate HT MCS would > > have more range than VHT, or something like that. I dont think so. basically if you remove 256 QAM out of picture, it just boils down to choosing a modulation scheme which would be same for VHT and HT. (assuming same BW) Only advantage is as Johannes pointed, VHT doesn't have greenfield, so using HT greenfield preamble might be marginally good. Similarly we can use RIFS for HT(not recommended), But again who uses RIFS/greenfield? -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: General VHT rate-ctrl question
On Wed, Apr 13, 2016 at 6:18 AM, Ben Greearwrote: > > > On 04/13/2016 01:01 AM, Johannes Berg wrote: >> >> On Tue, 2016-04-12 at 16:48 -0700, Ben Greear wrote: >>> >>> If a station and it's peer can both do VHT, is there ever a good >>> reason to even try HT rates? >>> >> >> Not really; perhaps if you could do HT greenfield preamble (which VHT >> doesn't have) you could get something out of it, beyond that I don't >> see a reason to try. >> >> Unless, for some strange reason, it supports only single stream VHT and >> dual-stream HT or something really weird? > > > I was wondering if there was ever a reason that, say 450Mbps HT > would work better than MCS-1 for VHT. Or, maybe a mid-rate HT MCS would > have more range than VHT, or something like that. > > After fighting with the firmware's rate-ctrl all day, I am even more > interested > in trying to make it use mistrel_ht. I just put up Andrew's old paper on minstrel, if that helps any. http://blog.cerowrt.org/post/minstrel/ > > Thanks, > Ben > > -- > Ben Greear > Candela Technologies Inc http://www.candelatech.com > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: General VHT rate-ctrl question
On 04/13/2016 01:01 AM, Johannes Berg wrote: On Tue, 2016-04-12 at 16:48 -0700, Ben Greear wrote: If a station and it's peer can both do VHT, is there ever a good reason to even try HT rates? Not really; perhaps if you could do HT greenfield preamble (which VHT doesn't have) you could get something out of it, beyond that I don't see a reason to try. Unless, for some strange reason, it supports only single stream VHT and dual-stream HT or something really weird? I was wondering if there was ever a reason that, say 450Mbps HT would work better than MCS-1 for VHT. Or, maybe a mid-rate HT MCS would have more range than VHT, or something like that. After fighting with the firmware's rate-ctrl all day, I am even more interested in trying to make it use mistrel_ht. Thanks, Ben -- Ben GreearCandela Technologies Inc http://www.candelatech.com -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: General VHT rate-ctrl question
On Tue, 2016-04-12 at 16:48 -0700, Ben Greear wrote: > If a station and it's peer can both do VHT, is there ever a good > reason to even try HT rates? > Not really; perhaps if you could do HT greenfield preamble (which VHT doesn't have) you could get something out of it, beyond that I don't see a reason to try. Unless, for some strange reason, it supports only single stream VHT and dual-stream HT or something really weird? johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
General VHT rate-ctrl question
If a station and it's peer can both do VHT, is there ever a good reason to even try HT rates? Thanks, Ben -- Ben GreearCandela Technologies Inc http://www.candelatech.com -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html