NAT64 and matching identities

Sat Nov 23 19:22:10 UTC 2013

So it turns out that in many cases a missing www is causing the "no IPv4"
response, and someone from Alexa does need to explain what is going on. For
the entire top-1m.csv file, 35,554 entries returned "no IPv4". For each
entry in the csv file;
some return NXDOMAIN:
discart.ru  -->  NXDOMAIN
     www.discart.ru resolves, but Alexa file missing www.
     Alexa position:            4721,discart.ru

some return without any answer:
bp.blogspot.com  --> No Answer
     www.bp.blogspot.com resolves, but Alexa file missing www.
     Alexa position:            87,bp.blogspot.com

while others point to MX-only entries:
akamaihd.net  -->  MX-only
     www.akamaihd.net resolves, but Alexa file missing www.
     Alexa position:            74,akamaihd.net

The version of the code I have been using strips the www. and tries again,
but obviously it also needs to add the www. and retry. In any case, the
Alexa file points to names that do not serve web content, so the entire 'top
1M' list is suspect.

Tony

> -----Original Message-----
> From: Tony Hain [mailto:alh-ietf at tndh.net]
> Sent: Friday, November 22, 2013 3:50 PM
> To: 'Owen DeLong'
> Cc: Sherfesee at amazon.com; 'NANOG List'
> Subject: RE: NAT64 and matching identities
> 
> Someone from Alexa really needs to answer how that list is created because
> their web site discussion is way too hand-wavy, but given that neither of
> those appear to be currently valid names, and 1.1.1.1 is on the list at
all, there
> must be some measure of cross link and redirection occurrences. For the
> entire top-1m, I show today's file has 2815 as dotted-quad. In the top
> 50,000 there are 1790 with "no IPv4   no IPv6".  Clearly they don't bother
> to prune the list for validity. ~4% of the next 25,000 names are dead
(50,000-
> 75,000), and one can only guess that as you get further down the list the
> percentage of dead names will continue to go up. I have a full 1M run in
> process, but would not count on it completing before Monday.
> 
> Just to add a level of 'extra effort' to the process, I increased the
number of
> attempts to 10, and the time between attempts to 10 seconds. With that,
> dead names in the top 1000:
> akamaihd.net                    no IPv4   no IPv6
> bp.blogspot.com                 no IPv4   no IPv6
> delta-search.com                no IPv4   no IPv6
> bannersdontwork.com             no IPv4   no IPv6
> cloudfront.net                  no IPv4   no IPv6
> doorblog.jp                     no IPv4   no IPv6
> uimserv.net                     no IPv4   no IPv6
> linksynergy.com                 no IPv4   no IPv6
> lipixeltrack.com                no IPv4   no IPv6
> australianbrewingcompany.com    no IPv4   no IPv6
> searchfun.in                    no IPv4   no IPv6
> greatappsdownload.com           no IPv4   no IPv6
> klikbca.com                     no IPv4   no IPv6
> jobfindgold.info                no IPv4   no IPv6
> adnxs.com                       no IPv4   no IPv6
> rakuten.ne.jp                   no IPv4   no IPv6
> sweetpacks-search.com           no IPv4   no IPv6
> yomiuri.co.jp                   no IPv4   no IPv6
> incredibar-search.com           no IPv4   no IPv6
> searchgol.com                   no IPv4   no IPv6
> livedoor.biz                    no IPv4   no IPv6
> workercn.cn                     no IPv4   no IPv6
> 
> FWIW: in the top 50,000, I show 1525 "has IPv4  has IPv6" &  0  "no IPv4
has
> IPv6". In other words, there are more dead names than there are AAAA
> records, and there are not any IPv6-only sites in that group.
> 
> Tony
> 
> 
> > -----Original Message-----
> > From: Owen DeLong [mailto:owen at delong.com]
> > Sent: Friday, November 22, 2013 1:48 PM
> > To: Tony Hain
> > Cc: joel jaeggli; Valdis.Kletnieks at vt.edu; NANOG List
> > Subject: Re: NAT64 and matching identities
> >
> > So one has to wonder how those names made it into the top 100 list if
> > it's supposed to be a top 100 web sites, since they are obviously not
> > web
> sites.
> > (at least in the case of the two in the top 100)
> >
> > Owen
> >
> > On Nov 22, 2013, at 1:28 PM, Tony Hain <alh-ietf at tndh.net> wrote:
> >
> > > The only thing it explicitly strips out are dotted-quads, which
> > > don't occur until # 4255. The code makes five passes at
> > > getaddrinfo() for
> > > IPv4 before giving up, and then it checks for a leading www and if
> > > that exists it strips it off and does the 5 tries loop again, then
> > > later the same process for IPv6. For the top 100 run:
> > > akamaihd.net                    no IPv4   no IPv6
> > > bp.blogspot.com                 no IPv4   no IPv6
> > >
> > > FWIW :::
> > > Dotted-quad's in the top 10,000
> > > 4255,92.242.195.24
> > > 4665,1.1.1.1
> > > 5079,92.242.195.231
> > > 6130,1.254.254.254
> > > 9518,208.98.30.70
> > >
> > >> whois 92.242.195.24
> > > ...
> > > netname:        Respina
> > > descr:          BroadBand IP Pool
> > > country:        IR
> > > ...
> > > route:          92.242.195.0/24
> > >
> > > Respina BroadBand IP Pool in the top 100,000
> > > 4255,92.242.195.24
> > > 5079,92.242.195.231
> > > 10059,92.242.195.233
> > > 23912,92.242.195.30
> > > 31520,92.242.195.111
> > > 35867,92.242.195.235
> > > 95233,92.242.195.129
> > >
> > >
> > >> -----Original Message-----
> > >> From: Owen DeLong [mailto:owen at delong.com]
> > >> Sent: Friday, November 22, 2013 12:16 PM
> > >> To: joel jaeggli
> > >> Cc: Valdis.Kletnieks at vt.edu; Tony Hain; NANOG List
> > >> Subject: Re: NAT64 and matching identities
> > >>
> > >> It would be way more than 2 if it were CNAME, methinks.
> > >>
> > >> Owen
> > >>
> > >> On Nov 22, 2013, at 12:12 PM, joel jaeggli <joelja at bogus.com> wrote:
> > >>
> > >>> On 11/22/13, 12:01 PM, Valdis.Kletnieks at vt.edu wrote:
> > >>>> On Fri, 22 Nov 2013 10:18:27 -0800, "Tony Hain" said:
> > >>>>
> > >>>>> The top 100 websites: AAAA records and IPv6 connectivity
> > >>>>>          count with A:       98   ( 98.000%)
> > >>>>>       count with AAAA:       30   ( 30.000%)
> > >>>>> Of the 30 hosts with AAAA records, testing connectivity to TCP/80:
> > >>>>>    count with IPv6 ok:       30   (100.000%)
> > >>>>
> > >>>> Statistics whoopsie, or are there actually 2 sites in the top100
> > >>>> that are IPv6-only?
> > >>>
> > >>> IN CNAME ? or is that being accounted for.
> > >>>
> > >>>
> > >>>
> 