[EXTERNAL] Re: A crazy idea

Feldman, Mark Mark_Feldman at comcast.com
Mon Jul 19 14:10:57 UTC 2021

On 7/19/21, 9:04 AM, "Stephen Satchell" <list at satchell.net> wrote:

    On 7/19/21 5:41 AM, Feldman, Mark wrote:
    > What you propose is not outlandish; some ISPs have been dual stack
    > and providing some combination of these services for years.  They
    > already provide IPv6 ip6.arpa delegations should their business
    > customers want them.  Some even provide at least a /56 so customers
    > can have multiple /64 subnets.  And we, I mean they, can also provide
    > RFC2317 in-addr.arpa delegations for those smaller IPv4 blocks.

    The part that is missing isn't the "some ISPs", it's "all ISPs".

It's true that not all ISPs do IPv6.  There are those that do support it and those that will.  At some point the pain associated with the lack of IPv4 address space will outweigh the pain of IPv6 deployment.   Those that do IPv6 should support all of the service that I described.

    I don't know of any DNS service provider that offers a product to handle
    delegations from the IN-ADDR.ARPA and IP6.ARPA trees.

Any DNS service provider should be able to host an in-addr.arpa or ip6.arpa zone.  If they don't do "reverse/PTR" zones, they're really not a full service provider.  Zones are zones.

    I'm focusing on the SOHO customer market with my proposal.

My standard residential service has my router getting a /64 that allows my hosts to self-generate public, routable /128 IPv6 addresses using EUI64 and other mechanisms when I don't bother setting the RHS of the address.   I also get a single IPv4 address which gets NAT'd.   There's no reason for a SOHO customer to have less than that and there are reasons to have more.

Every modern device in my house preferes IPv6 when the service to which it is connecting is dual stack.  It all just works as-is.  When things break, it's usually an antiquated piece of equipment  that doesn't grok IPv6 itself or there's one in the way.

Most of our residential customers don't pay attention the underlying protocols.  They just plug things in and use them.  Well over half of the DNS queries coming from our customers come in over IPv6.

    The allocation of IPv6 space with prefixes shorter than /64 is indeed a
    consideration for bigger administrative domains like country
    governments, but on the other end, SOHO customers would be happy with
    /96, /104 or even /112 allocations if they could get them.  (Just how
    many light bulbs, fridges, toasters, doorbells, phones, &c does SOHOs
    have?)  I would *not* like to see "us" make the same mistake with IPv6
    that was made with IPv4, handing out large blocks of space like so many
    pieces of M&M or Skittles candy.

The standard for an IPv6 subnet is a /64.  It's what makes EUI64  and other useful addressing techniques possible.  You can't think of IPv6 with an IPv4 scarcity mindset -- that will cause you to cripple IPv6.  And, no, even with /64 subnets, you won't run out of IPv6 addresses -- there are still billions of times more subnets available with IPv6  than there are host addresses in IPv4.

Making the standard subnet a /64 and having IPv6 delegations fall on nibble boundaries means a clean mapping to DNS without RFC2317 games.

We used to have someone with the title, IPv6 Evangelist.  He got us far.  Now it's everyone's job.


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