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Is there a good estimate to how many ipv6 prefixes are currently being used?

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up vote 8 down vote accepted

If by 'in use' you mean 'seen in the DFZ': around 20K. The NLNOG Ring has a nice dashboard on which is summarizes the number of prefixes their lookingglass receives from members. As you can see here, just over 20K prefixes can be seen there.

APNIC currently reports a bit less: about 18.5K prefixes, Hurricane Electric reports just under 18K. The IP transit providers my current employer uses all advertise just over 18K prefixes.

There's no single correct answer here, it all depends on the filter policies networks and their upstreams use and how all networks on the internet are connected, but it's fair to say that 'around 20K' is a good approximation.

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@Teun_Vink is there a similar hurricane electric report for ipv4? – user3754317 Aug 6 '14 at 18:22
HE doesn't seem to have it, they're more interested in IPv6. I couldn't find another source, maybe people don't put it only due to its size (>530K active routes). – Teun Vink Aug 6 '14 at 19:40
@Teun_Vink Thanks a lot! I'm trying to build an ip database but can't afford the commerical access so I'm trying to scrape the data and wanted to get a rough estimate as to how well it worked. – user3754317 Aug 6 '14 at 20:37

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