nanog mailing list archives
Re: IPv6 woes - RFC
From: Baldur Norddahl <baldur.norddahl () gmail com>
Date: Wed, 22 Sep 2021 21:45:47 +0200
On Wed, 22 Sept 2021 at 16:48, Masataka Ohta < mohta () necom830 hpcl titech ac jp> wrote:
Today, as /24 can afford hundreds of thousands of subscribers by NAT, only very large retail ISPs need more than one announcement for IPv4.
You can only have about 200-300 subscribers per IPv4 address on a CGN. If you try to go further than that, for example by using symmetric NAT, you will increase the number of customers that want to get a public IPv4 of their own. That will actually decrease the combined efficiency and cause you to need more, not less, IPv4 addresses. Without checking our numbers, I believe we have at least 10% of the customers that are paying for a public IPv4 to escape our CGN. This means a /24 will only be enough for about 2500 customers maximum. The "nat escapers" drown out the efficiency of the NAT pool. The optimization you need to do is to make the CGN as customer friendly as possible instead of trying to squeeze the maximum customers per CGN IPv4 address. Perhaps IPv6 can lower the number of people that need to escape IPv4 nat. If it helps just a little bit, that alone will make implementing IPv6 worth it for smaller emerging operators. Buying IPv4 has become very expensive. Yes you can profit from selling a public IPv4 address to the customer, but there is also the risk that the customer just goes to the incumbent, which has old large pools of IPv4 and provides it for free. Regards, Baldur
Current thread:
- Re: IPv6 woes - RFC, (continued)
- Re: IPv6 woes - RFC Masataka Ohta (Sep 18)
- Re: IPv6 woes - RFC Saku Ytti (Sep 19)
- Re: IPv6 woes - RFC Masataka Ohta (Sep 19)
- Re: IPv6 woes - RFC Stephen Satchell (Sep 19)
- Re: IPv6 woes - RFC Owen DeLong via NANOG (Sep 19)
- Re: IPv6 woes - RFC Masataka Ohta (Sep 20)
- RE: IPv6 woes - RFC Brian Turnbow via NANOG (Sep 20)
- Re: IPv6 woes - RFC Owen DeLong via NANOG (Sep 20)
- Re: IPv6 woes - RFC Owen DeLong via NANOG (Sep 20)
- Re: IPv6 woes - RFC Masataka Ohta (Sep 22)
- Re: IPv6 woes - RFC Baldur Norddahl (Sep 22)
- Re: IPv6 woes - RFC Colton Conor (Sep 22)
- Re: IPv6 woes - RFC Mark Andrews (Sep 22)
- Re: IPv6 woes - RFC Colton Conor (Sep 23)
- Re: IPv6 woes - RFC Eric Kuhnke (Sep 23)
- Re: IPv6 woes - RFC Mark Andrews (Sep 23)
- Re: IPv6 woes - RFC Baldur Norddahl (Sep 23)
- Re: IPv6 woes - RFC Christopher Morrow (Sep 23)
- Re: IPv6 woes - RFC Baldur Norddahl (Sep 23)
- Re: IPv6 woes - RFC Christopher Morrow (Sep 23)
- Re: IPv6 woes - RFC Owen DeLong via NANOG (Sep 22)