From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bobcat.rjmcmahon.com (bobcat.rjmcmahon.com [45.33.58.123]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 1578F3CBC5; Wed, 15 Mar 2023 15:39:34 -0400 (EDT) Received: from mail.rjmcmahon.com (bobcat.rjmcmahon.com [45.33.58.123]) by bobcat.rjmcmahon.com (Postfix) with ESMTPA id 280281EEE8; Wed, 15 Mar 2023 12:39:33 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 bobcat.rjmcmahon.com 280281EEE8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rjmcmahon.com; s=bobcat; t=1678909173; bh=Q3PZZc5bHJ4YDNNPO9rzogg+/dn9aclaDQDkUcmE+QI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=MxrdDEN0ml80bUxt1VxuDWWdgo6VchRIQ7xvTZrTHUhEMFh7LEtl9gUVYBHugVQvg cfaOepGxMBz2KN5NwPY//63ejFvCJKrOlbWtQ0u5URvtkt8N/OD2/ilCR3JKi5lyiN 1/g0whSxw78YAyC40t54WFUGMMIetgjtKHWXiw2o= MIME-Version: 1.0 Date: Wed, 15 Mar 2023 12:39:33 -0700 From: rjmcmahon To: Dave Taht Cc: Sebastian Moeller , Rpm , dan , Bruce Perens , libreqos , Dave Taht via Starlink , bloat In-Reply-To: References: <22C819FA-DDD7-4B9B-8C09-8008D4273287@gmx.de> <5e7fac51071bdbb20837e72e7eedfc7c@rjmcmahon.com> <3f45d2a0b6e46d7b2775fb801e805f93@rjmcmahon.com> <70F71290-C6CB-4D19-8A88-F0F17C0BDDA2@gmx.de> <5e0cd693c4749d128dbb48d6c1129071@rjmcmahon.com> <2ab2983d-6beb-49cb-8c35-e481cbfdc7a3@Spark> <89c55d67-86f0-494d-a09e-c9aeebe46dc0@rjmcmahon.com> <70CBB03C-4394-4A93-BBB5-7449DC1AAF9C@gmx.de> <063359bf-5bf3-4688-852c-a7d81e6b80a3@rjmcmahon.com> <21f2252ff57e60dc52e7b9a6db8ba936@rjmcmahon.com> <8a04de1c-2d47-4226-a1ac-ea3d5e7b7253@rjmcmahon.com> <949886c0f65025a626887d09a818c233@rjmcmahon.com> <7d7d508f127db23c1904f7f08946d674@rjmcmahon.com> Message-ID: <0c59999b3bb49758cf4f923c47528fc1@rjmcmahon.com> X-Sender: rjmcmahon@rjmcmahon.com Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Rpm] [Bloat] [Starlink] [LibreQoS] On FiWi X-BeenThere: rpm@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: revolutions per minute - a new metric for measuring responsiveness List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Mar 2023 19:39:34 -0000 > I have sometimes thought that LiFi (https://lifi.co/) would suddenly > come out of the woodwork, > and we would be networking over that through the household. I think the wishful thinking is "coming from woodwork" vs coming from the current and near future state of engineering. Engineering comes from humans solving problems who typically get paid to do so. FiWi would leverage SFP tech. The Fi side of FiWi comes from mass NRE investments into the data center networks. The Wi side from mass investment into billions of mobile phones. Leveraging WiFi & SFP parts is critical to success as semiconductors are a by-the-pound business. I think a 1X25G VCSEL SFP, which is tolerant to dust over MMF, has a retail price of $40 today. The sweet spot for DC SFP today is driven by 1x100Gb/s serdes and I suspect angel investors are trying to improve the power significantly of the attached lasers. It's been said that one order of improvement in lowering laser power gives multiple orders of laser MTBF improvements. So lasers, SERDES & CMOS radios are not static and will constantly improve year to year per thousands of engineers working on them today, tomorrow & on. The important parts of FiWi have to be pluggable - just like a light bulb is. The socket and wiring last (a la the fiber and antennas) - we just swap a bulb if it burns out, if we want a different color, if we want a higher foot candle rating, etc. This allows engineering cadences to match market cadences and pays staffs. Most engineers don't like to wait decades between releases so-to-speak and don't like feast & famine lifestyles. Moore's law was and is about human cadences too. I don't see any engineering NRE that LiFi could leverage. Sounds cool though. Bob