[lacnog] Question about 240/4 space

[Fernando Frediani]

Hello folks

I wanted to put a question about this topic in order to learn a bit 
deeper into this question from the community who have better knowledge 
about it, specially those who have more IETF involvement.

The last time I asked why still the 240/4 wasn't turned into usable /8's 
to be distributed to all RIRs and therefore to LIRs and End-users. The 
explanation I was given at the time was that people considered it for 
quiet a while and came to a conclusion that was not worth the cost of 
'changing everything needed to be changed' in order to make it work as 
expected. Some have mentioned that some network firmware had embedded in 
it to not even forward packets in this IP space.
On this basis I wanted also to understand also who was the 'clever' idea 
to deny forwarding to this packets in firmware to something tagged as 
"Future Use", therefore that had the expectation to be used one day in 
the future ?

I am asking this because I have been reading some 'yet again' proposals 
to make it viable and wanted to understand what are the the biggest 
technical challenges to make it viable.
If it is true that some firmware have this limitation, and it goes down 
to a CPE level I can start understanding the amount of work to get every 
single equipment updated to be able to talk to these future networks. 
Even in a ISP/Telecom level one thing that comes to mind is where you 
have very old and EOF routers still in production and people refusing to 
take them our of production, no doubt even if Network vendors would 
provide an updated firmware version those routers would never receive 
it. Besides that what other big concerns are in your view ?

With regards the points some people frequently raise about that any 
extension to IPv4 space is a killer to IPv6 Deployments to come, I 
personally refuse to believe in that, at least not in a binary way was 
sometimes is preached. I see that regardless the improvements in IPv6 
deployment (which I obviously support and actively practice on my day by 
day) I always had the impression that we will live with the IPv4 
internet for at least, in a very optimistic scenario for another 10 
years or more. Recently I read a report about this subject that 
mentioned at least another 20 years.

And even when it is said that no matter how much IPv4 becomes available 
it will never be enough and would be exhausted quiet quickly (probably 
true). Well, I would say that if there is any chance for these 'new' 
IPv4 to become functional they should never be intended to be used as 
they have been in the last decades, but instead to certain and specific 
usages as mainly facilitate IPv6 deployment and translation techniques, 
Hosting and other scenarios where no-IPv4-at-all is not an option.

Appreciate any comments and contributions to make it possible to 
understand this subject better.

Best regards
Fernando Frediani