Paris Traceroute

UNDER CONSTRUCTION

In this section we aim at building an exhaustive list of all the interesting or strange things that you can see when you traceroute the Internet.
We propose two classifications:

• By causes:
  • Load balancing
    • Per-flow load balancing
    • Per-packet load balancing
    • Loops
    • Cycles
    • False links
  • Per-destination load balancing
  • Ghost routers
  • NAT
    • NAT boxes
      
    • Buggy NAT boxes
    • Strange loop at Bouira ISP
    • Per-protocol NAT
  • MPLS
    • Labels
      
    • Label stack
    • Incrementing original and response TTLs
    • Incrementing MPLS TTL
    • Label bug?
  • Stars
    • ICMP-suppressing routers
    • ICMP-limiting routers
    • ICMP-suppressing destinations
  • Private IP addresses
  • Routing loops
  • Misc
    • Routers sending IP options
    • Null IP Identifier
    • 0-TTL without a loop
• By effects:
  • Loops
  • Cycles

   

Loops and load balancing

Figure 1 A loop caused by load balancing