Path: ...!weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: Dan Purgert Newsgroups: sci.electronics.design Subject: Re: "Safe" cell phone WiFi capabilities? Date: Mon, 20 May 2024 17:03:40 -0000 (UTC) Organization: A noiseless patient Spider Lines: 78 Message-ID: References: Injection-Date: Mon, 20 May 2024 19:03:41 +0200 (CEST) Injection-Info: dont-email.me; posting-host="b004ff933cbbe5d37a325e03bf5d1512"; logging-data="112093"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/OGRrq9RWdpsLRDdygbyj/TZ/LIxRaxdc=" User-Agent: slrn/1.0.3 (Linux) Cancel-Lock: sha1:fd62oshp5rctmUzjeGy5ZDWRamE= Bytes: 4489 On 2024-05-20, Don Y wrote: > On 5/20/2024 4:37 AM, Dan Purgert wrote: >> On 2024-05-20, Don Y wrote: >>> On 5/20/2024 4:02 AM, Dan Purgert wrote: >>>> On 2024-05-17, Don Y wrote: >>>>> On 5/17/2024 5:55 AM, Dan Purgert wrote: >>>>>> On 2024-05-17, Don Y wrote: >>>>>>> For "nominal" cell phones (i.e., taking into consideration >>>>>>> that not ever subscriber buys The Latest and Greatest), >>>>>>> what's the "base" WiFi capability one would feel comfortable >>>>>>> assuming? ac? ax? >>>>>> >>>>>> Assuming you're limiting the question to the set of cellphones that >>>>>> actually implement wifi, 802.11b ... but what are you *REALLY* >>>>>> trying to ask for? >>>>> >>>>> There are several different "generations" of WiFi, each with >>>>> different effective (data) bandwidths. >>>>> [...] >>>> >>>> No. /FLAGSHIP/ models certainly have a high chance of supporting >>>> 802.11ax, but that doesn't mean "any" phone. >>>> >>>> Again, what are you *REALLY* trying to ascertain here? >>> >>> But, in practice, most phones support something more capable >>> than 802.11b -- just like most enets support something more >>> capable than 10BaseT/2. >> >> It's almost like "the base" isn't what you want then. >> [...] >> Which is why you toss in an 802.11ax AP (or 802.11ac, if the ax units >> are prohibitively expensive for your house/office/whatever), and leave >> it up to the client device to negotiate for the best common option. > > And, when you want to pass a gigabit of data to the phone each second, > how does that AP help the phone GET the data when the pipe TO THE HANDSET > is considerably narrower?! Then I buy a phone that can support 802.11ac Wave2 with 160 MHz channel width, and at least 3x3 spatial streams. Assuming, of course: - that the AP supports those minimum requirements as well, AND - The conditions allow for negotiation of MCS8 (~2300 mbps link rate, ballpark 1gpbs sustained data rate, but WiFi math is "fun") AND - There aren't other devices also requesting airtime (especially ones using slower options -- 2x2 streams, 802.11n, MCS5, etc.) AND - The server has enough bandwidth (incl. read buffers, disk I/O, etc.) to sustain that 1gpbs transfer to my phone. - The phone has enough bandwidth (incl. write buffers, "disk" I/O, etc.) to sustain a 1gbps transfer from the server. Or, I don't use WiFi (to a phone or otherwise) because if I *need* 1gpbs, then a wire's gonna give me that without any of the conditions imposed by half-duplex radio communications. > >> It's not like an 802.11ax AP doesn't support a/b/g/n/ac ... > > You're missing the point, completely. It's almost like the whole reason I've repeatedly asked "what do you *REALLY* want to know" is because your question is vague. - If you're building some form of WiFi access point --> who cares, the phone will negotiate with the AP for the best common mode between them given local conditions (e.g. 802.11n @ MCS2) - If you're building some form of application that needs some minimum data rate --> you can't really guarantee you're going to get that rate, unless it's less than 1Mbps (802.11a/b/g) or MCS0 (802.11n/ac/ax; exact rate varies depending on available spatial streams). -- |_|O|_| |_|_|O| Github: https://github.com/dpurgert |O|O|O| PGP: DDAB 23FB 19FA 7D85 1CC1 E067 6D65 70E5 4CE7 2860