CC: s to Non List Members (was Re: 202203080924.AYC Re: 202203071610.AYC Re: Making Use of 240/4 NetBlock)

John R. Levine johnl at
Wed Mar 9 02:06:50 UTC 2022

> The only way IPv6 will ever be ubiquitous is if there comes a time where
> there is some forcing event that requires it to be.
> Unless that occurs, people will continue to spend time and energy coming up
> with ways to squeeze the blood out of v4 that could have been used to get
> v6 going instead.

I agree.  There is a great deal of unused or underused v4 space that 
increasing prices have found and even if the long term cost of setting up 
v6 is lower, it's more than the short term cost to buy another v4 block.

This still doesn't mean that screwing around with 240/4 or, an even worse 
127/8 minus 127/24, is a good idea.

John Levine, johnl at, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail.

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