RE: Why /64

[Wuyts Carl <[e-mail]>]

Hi Sander,

Don't worry, I agree upon your statements wrt size of prefix, and always recommend our customers a /56 (or bigger), and this is for residential CPE, so I'm not really talking about "home-office" networks.
Reality today however says that the majority of users today is using a single /64 which I believe makes the ISP think on the size of the ia_pd to be used, hence they might select something smaller, also to get more value in the future for using bigger ones (for more advanced users), so it's sort of a trade-off I believe.

Nevertheless, /64, the topic of these mails, on links should be kept imho, so not start tweaking them smaller just because some ISPs only handout some smaller ia_pd.  Arin guidelines seems to be in place for /56, should not be a bad idea to have this being used globally, but might not be that easy to enforce.

Regs
Carl

-----Original Message-----
From: Sander Steffann [mailto:[e-mail]] 
Sent: maandag 28 oktober 2013 10:23
To: Wuyts Carl
Cc: Jeroen Massar; Octavio Alvarez; <[e-mail]>
Subject: Re: Why /64

Hi Carl,

> +1 for the /64 on the link and /48 for enterprise, 
> 
> but "at least" a /56 for home (with /60 too tiny) ??
> Can you elaborate on why you would need more than 4 bits subnets @ home?

Today 4 bits can be enough for simple cases with i.e. a home network, a guest network and maybe a home-office network. But IPv6 is meant to last for some time, and in the (near) future it is not that difficult to see networks for lighting and sensors (i.e. 6lowPAN) being added to that. And I'm not being very creative right now ;-)  Besides: home users often don't understand the different between a wireless router and an access point, so they tend to daisy-chain them. In IPv4 this would cause multiple layers of NAT, in IPv6 you need more subnets.

PS: Look at DT's plans, they are giving multiple /56s to each home. One for best-effort internet access, one for voice, one for streaming audio/video, etc. See https://ripe67.ripe.net/presentations/131-ripe2-2.pdf. I'm not saying this is the way everybody should deploy IPv6, but it is an example of using IPv6 address space in a different way.

Cheers,
Sander