nanog mailing list archives
Re: A straightforward transition plan (was: Re: V6 still not supported)
From: Ca By <cb.list6 () gmail com>
Date: Mon, 28 Mar 2022 06:45:50 -0700
On Mon, Mar 28, 2022 at 6:22 AM Philip Homburg <pch-nanog-2 () u-1 phicoh com> wrote:
If by ?straightforward transition plan? one means a clear and rationalset ofoptions that allows networks to plan their own migration from IPv4-onlyto IPv6, while maintaining connectivity to IPv4-only hosts and with a level ofeffort reasonable comparable to just running IPv4, then I would disagree, assuch an "IPng transition plan? was achievable, expected, and we collectivelyfailedto deliver on it (as noted below)I'm a bit confused about the achievable part. Obviously, the adoption of IPv6 without a clear transition plan was a process failure. However, it is not clear to me that waiting a few years would have brought something much better. And waiting more than a decade would mean that today there would not be a mature IPv6. Transition to IPv6 so far seems to have consisted of 3 phases: 1) Lots of tunnels due lack of a wide spread IPv6 backbone. 2) Early adopters being happy that they can run IPv6 native, usually as dual stack. 3) Lots of people looking into IPv6-only. I'd say 1) mostly worked. 6to4 was a bit of mess. But otherwise tunnels worked. Obviously, deploying IPv6 using tunnels is a lot more complex than deploying native IPv4 without NAT. From a technical perspective 2) just works. From an operational perspective it is about twice as expensive as IPv4-only. So 2) is popular with people who really want IPv6. The big issue is 3). If we look at the current internet, there are parties who lack IPv4 addresses and want to switch to IPv6. Obviously, they want to be IPv6-only. The lack of IPv4 address makes dual stack even harder. On the other hand, there are parties who have enough IPv4 addresses and have no reason to switch to IPv6. So we are clearly in the situation of 'migration from IPv4-only to IPv6, while maintaining connectivity to IPv4-only hosts' It should be clear that an IPv4-only host only speaks IPv4. This means that communication with an IPv4-only host has to be IPv4. So either the IPv6-only host or something in the network has to speak IPv4. If the IPv6 host speaks IPv4 then we get dual stack, which has been rejected as a broken solution. Technically, it is also possible to tunnel IPv4 packets, then the host is in some sense dual stack, but most of the network is not. However, automatic tunnel configuration is hard, and tunnels tend to be fragile. So the only option is a device in the network that translates between IPv6 and IPv4. Currently we have such a protocol, NAT64. And from a technical point of view it is a disaster.
I think what you mean to say is you don’t like NAT64. You may also be trying to say you disapprove of how history unfolded. Fair. But it may be worth acknowledge that some small and some very large (100M mobiles, growing FWA broadband business) have happily operated NAT64 for coming on 10 years with no problems or regrets. Yes, we would like the internet to be on a single unified and high scale address family, but we all play the hand we are dealt.
Looking back, we can say that the only feature of IPv6 that makes people invest in IPv6 is the bigger address space. So it is safe to say that most of the internet would have waited to invest in IPv6 until we were (almost) out of IPv4 addresses. So by its very nature this transation between IPv6 and IPv4 would have NAT component. In my opinion, It is clear that during the time IPv6 was developed, any solution involving NAT would have been rejected. So I'm confused, what transition technology was achievable (also in the political sense) but not delivered? If there is a magical transition technology that allows an IPv6-only host to talk to an IPv4-only host, then let's deploy it.
Current thread:
- RE: V6 still not supported, (continued)
- RE: V6 still not supported Ryland Kremeier (Mar 28)
- Re: V6 still not supported Owen DeLong via NANOG (Mar 30)
- Re: V6 still not supported Matthew Craig (Mar 25)
- A straightforward transition plan (was: Re: V6 still not supported) John Curran (Mar 24)
- Re: A straightforward transition plan (was: Re: V6 still not supported) Philip Homburg (Mar 28)
- Re: A straightforward transition plan (was: Re: V6 still not supported) John Curran (Mar 25)
- Re: A straightforward transition plan (was: Re: V6 still not supported) Philip Homburg (Mar 28)
- Re: A straightforward transition plan (was: Re: V6 still not supported) Mark Andrews (Mar 30)
- RE: A straightforward transition plan (was: Re: V6 still not supported) Pascal Thubert (pthubert) via NANOG (Mar 31)
- Re: A straightforward transition plan (was: Re: V6 still not supported) JORDI PALET MARTINEZ via NANOG (Mar 28)
- Re: A straightforward transition plan (was: Re: V6 still not supported) Ca By (Mar 28)
- Re: A straightforward transition plan (was: Re: V6 still not supported) Joe Maimon (Mar 28)
- Re: V6 still not supported Masataka Ohta (Mar 24)
- RE: V6 still not supported Pascal Thubert (pthubert) via NANOG (Mar 23)
- Re: V6 still not supported Re: 202203231017.AYC Abraham Y. Chen (Mar 23)
- RE: V6 still not supported Re: 202203231017.AYC Pascal Thubert (pthubert) via NANOG (Mar 23)
- Message not available
- Re: V6 still not supported R: 202203232156.AYC Abraham Y. Chen (Mar 25)
- Re: V6 still not supported Re: 202203231017.AYC Abraham Y. Chen (Mar 25)
- Re: V6 still not supported Masataka Ohta (Mar 22)
- Re: V6 still not supported bzs (Mar 18)
- Re: V6 still not supported Michael Thomas (Mar 18)