It is difficult to understand how is it possible to claim that transmission of additional 20Bytes would not consume more energy? Brian, how it could be that Base Station or Core router could break the law of physics?? Especially in the situation when they could not look and optimize anything inside the GTP tunnel. At first glance, less energy efficiency should be 20/800=2.5% (many reports on the average packet size 750 - 800 bytes), But look at this research https://www.matec-conferences.org/articles/matecconf/pdf/2019/41/matecconf_cscc2019_03002.pdf on how chatty ND is. Effectively, IPv6 average packet size is smaller on the 1st hop and many additional packets would be generated. I have understood now why it could be 5% for a smartphone. I trust this estimation. The argument of Brian about CGNAT's absence is the strong one. Let's investigate it a little more carefully. Let's assume the worst is that the host and the server would waste 5 more points of energy each (that is probably not true for the server where the percentage of ND packets would be less). Let's assume that 6 hops are between the host and the server that have 10x better energy efficiency per bit (because of hardware forwarding and switching). It would give 6*5/10=3 additional points of energy consumption for all 6 hops (here again the worst case is because ND may be completely absent on networking hops, then deficiency would drop 5%-> 2.5%). Let's assume that CGNAT is 3x more efficient than host/server. It would give energy savings of 100/3=33 points. 33>>13. (in reality, would be even better after more careful calculation) Hence, the full E2E picture with CGNAT permits to claim that IPv6 has considerable savings of energy. PS: Ignoring the evident (that additional 20 bytes would consume more energy on every hop) would undermine the trust in IETF. Eduard -----Original Message----- From: ietf [mailto:ietf-bounces@xxxxxxxx] On Behalf Of Brian E Carpenter Sent: Tuesday, November 23, 2021 12:31 AM To: Nick Hilliard <nick@xxxxxxxxxx>; John Levine <johnl@xxxxxxxxx> Cc: ietf@xxxxxxxx Subject: Re: IPv6 causes global warming On 23-Nov-21 08:19, Nick Hilliard wrote: > John Levine wrote on 22/11/2021 18:50: >> But does anyone have any idea what this "report' might be? > > draft-petrescu-v6ops-ipv6-power-ipv4? > > The methodology raises questions about whether the results are > reliable enough to be quoted. Regardless of that, it's far from clear that even if those results were valid in 2017 that they are still valid today, and how they relate to total power consumption, because for all I know base stations use 10% less power for IPv6 and core routers use 12.5% less. Warren, shall I write a draft raising those hypotheses? How much power is being wasted at this moment by domestic NATs and CGN boxes? Brian
