  Over the past decade, IXPs have been playing a key role in enabling
interdomain connectivity. Their traffic volumes have grown dramatically and
their physical presence has spread throughout the world. While the relevance of
IXPs is undeniable, their long-term contribution to the shaping of the current
Internet is not fully understood yet.
  In this paper, we look into the impact on Internet routes of the intense IXP
growth over the last decade. We observe that while in general IXPs only have a
small effect in path shortening, very large networks do enjoy a clear
IXP-enabled path reduction. We also observe a diversion of the routes, away
from the central Tier-1 ASes supported by IXPs. Interestingly, we also find
that whereas IXP membership has grown, large and central ASes have steadily
moved away from public IXP peerings, whereas smaller ones have embraced them.
Despite all this changes, we find though that a clear hierarchy remains, with a
small group of highly central networks
