On Thu, Nov 24, 2016 at 7:05 PM Adam <adam...@gmail.com> wrote: > I'm crunching the numbers on the cost effectiveness of implementing CGN vs > IPv4 auctions. The determining factor is how many ephemeral ports are > reserved for each customer. This is for a residential broadband > environment. > > Is anybody doing deterministic NAT/PAT (i.e. each customer gets X ports - > no more, no less)? My thinking is that X=8192 would cover even the power > users. However, with only 8 customers per public IPv4 address, CGN is not > worth the trouble. With X=8192, our money and time would better be spent > acquiring additional IPv4 space. Are people successfully using a smaller > deterministic port allocation? What's your X? > > If I can't make the numbers work for deterministic NAT, I might be able to > live with dynamic port assignments. Specifically, I'm referring to what > vendor J calls "Port Block Allocation". I was thinking 1024 ports per > block, with up to 8 blocks per customer (and a bunch of log correlation to > determine who was using which ip:port tuple at a given datetime). I *can* > make the math work out in favor of CGN if the average customer uses <= 3072 > ports (3 blocks). But is that going to be enough? I'd love to hear other > people's experiences. > > Thanks! > -Adam >
We see around 70% of traffic using ipv6 (goog, fb, netflix, ... now cloudfront and Cloudflare ) , that takes a lot of the sting out of CGN cost. CB
