Dear list, First of all, let me apologize if this post is not allowed by the list. To my best interpretation of the guidelines [1] it is allowed, but may be in a gray area due to rule #7. I would like to propose the following thought experiment about IPv6, and I would like your opinion on what you believe would happen in such a case. Feel free to reply on or off list. What if, globally, and starting at January 1st, 2020, someone (imagine a government or similar, but with global reach) imposed an IPv4 tax. For every IPv4 address on the Global Internet Routing Table, you had to pay a tax. Let’s assume that this can be imposed, must be paid, and cannot be avoided using some loophole. Let’s say that this tax would be $2, and it would double, every 3 or 6 months. What do you think would happen? Would it be the only way to reach 100% IPv6 deployment, or even that wouldn’t be sufficient? And for bonus points, consider the following: what if all certification bodies of equipment, for certifications like FCC’s or CE in Europe, for applications after Jan 1st 2023 would include a “MUST NOT support IPv4”.. What I am trying to understand is whether deploying IPv6 is a pure financial problem. If it is, in this scenario, it would very very soon become much more pricey to not deploy it. I know there are a lot of gaps in this, for example who imposes this, what is the "Global Internet Routing Table", etc. but let’s try to see around them, to the core idea behind them. Thanks, Antonis ------- Links ------- 1: https://nanog.org/resources/usage-guidelines/ <https://nanog.org/resources/usage-guidelines/>