Prefix distribution


/24 prefixes
the smallest globally routable address blocks
58% of the table, fraction stable since 1997

Q: Is proportion of /24s in backbone tables growing?
      A: No
Since 1998, the share of /24s has stayed between 57% and 58.5%
Has decreased since then by 0.6%-0.9% in all non-filtered tables

About 1/2 of all prefixes are more specifics (subsets).
1999 50%
2000 55%
2001 52%