IPv6 only with IPv4 CGNAT describes most of the large mobile network providers at least in the US.
> On Jun 19, 2025, at 6:05 PM, Forrest Christian (List Account) via NANOG > <[email protected]> wrote: > > Just to provide some perspective from my viewpoint: > > I can run dual-stack. But I don't want to, at least for a specific > customer. I want a particular customer to be IPv4 or IPv6, with an > eventual transition to 100% IPv6. > > I don't want to restart the recurring argument, but I'll just put this out > there: Why bother adding the cost of supporting a dual-stack network when > there is precisely zero cost for me to stick with IPv4? From a cost > perspective, if I have to assign everyone an IPv4 address and an IPv6 > address to deploy IPv6, why would I bother assigning the IPv6 address? I > have plenty of addresses to continue handing out IPv4 addresses directly to > customers for at least several years, so there is no benefit to me in > adding the overhead of dealing with both IPv6 and IPv4 on a per-customer > basis simultaneously. > > However, I'm willing to migrate (over several years) to an IPv6-only > network and run a CGNAT box to access IPv4, but only once the cost of > running the CGNAT box becomes negligible. Once that occurs, I want to start > getting ahead of the curve and set up a CGNAT box, then begin offering only > IPv6 to new customers. > > Of course, the size and cost of the CGNAT device are directly related to > the flows and/or bandwidth, which is why I was curious about the > percentages. If it's 10% IPv6, then I'm not close to where I need to be. > If it's 95%, then I can (and should) start moving to IPv6. Somewhere in > the middle is the threshold, not quite sure where that number is. > > >> On Thu, Jun 19, 2025 at 3:24 PM Mark Andrews via NANOG < >> [email protected]> wrote: >> >> You are asking the wrong question. >> >> Switching on IPv6 doesn’t require you to switch off IPv4. You can but you >> don’t have to. I find it sad that ISPs still think IPv4 and IPv6 are >> mutually exclusive. Nobody is asking for people to switch off IPv4. They >> are only asking that you enable IPv6 so they can reach you without having >> to run the traffic though a CGN 44 or 64. >> >> For most eyeball networks the majority of your traffic will be IPv6 the >> moment you turn IPv6 on as most of the large content providers offer IPv6 >> and implementations prefer IPv6. >> >> Mark >> -- >> Mark Andrews >> >>> On 20 Jun 2025, at 06:13, Forrest Christian (List Account) via NANOG < >> [email protected]> wrote: >>> >>> I see numerous statistics from Google and similar sources that indicate >> the >>> percentage of end users who are IPv6 native. What I'm missing are >>> statistics going the other way - what percentage of sites (or endpoints >>> that customers regularly connect to) are IPv6-native, from a total >> traffic >>> perspective? >>> >>> That is, if I switch to IPv6 on my eyeball network, how much of my >> existing >>> traffic will I have to CGNAT in some way to reach the IPv4-only network? >>> >>> We have sufficient IPv4 address resources to stick with IPv4 for the >>> foreseeable future. However, at some point, the percentage of traffic >>> using IPv6 becomes so high that the reasons not to move become less >>> significant. For example, the CGNAT box becomes significantly smaller, >> as >>> most of the traffic should flow around it on IPv6. >>> >>> -- >>> - Forrest >>> _______________________________________________ >>> NANOG mailing list >>> >> https://lists.nanog.org/archives/list/[email protected]/message/ZWNAGD3GM6VKKNBE3QE5HHRJ26C4UXJF/ >> >> _______________________________________________ >> NANOG mailing list >> >> https://lists.nanog.org/archives/list/[email protected]/message/A75BIETJQDTWUGEZQWSGKNE2L5SQPNHZ/ > > > > -- > - Forrest > _______________________________________________ > NANOG mailing list > https://lists.nanog.org/archives/list/[email protected]/message/FKFUZUB57MSQ7PNRVE5IUKTJL345WEET/ _______________________________________________ NANOG mailing list https://lists.nanog.org/archives/list/[email protected]/message/RX3FECTHEFDGFSDTMDFS7NBQK7D57CFW/
