A Characterization of Load Balancing on the IPv6 Internet

As IPv6 deployment grows, it is important to develop new measurement techniques that allow us to study the IPv6 Internet. We implement an IPv6 version of the Multipath Detection Algorithm and use it from 12 geographically-distributed vantage points on two different platforms to characterize IPv6 routers that perform load balancing. Overall, we find that 74% of IPv6 routes traverse at least one router that performs load balancing. Similar to previous reports for IPv4, we find per-destination is the most prevalent type of load balancing; surprisingly, we find a significantly higher prevalence of per-packet load balancing for IPv6 traffic than previously reported for IPv4. We investigate which header fields are used for load balancing, and find that 4% of IPv6 routers that perform load balancing consider IPv6’s Traffic Class or Flow Label fields. Finally, we quantify how often routers modify the Traffic Class and Flow Label IPv6 header fields and their impact on load balancing.