3.3 Choosing Nodes

• What nodes to put in a slice are dependent upon what you're trying to do
• Choose all nodes
• Choose randomly
• Choose based on geographical location
• Choose based on some other factor
• Note there are some nodes which can't be reached from everywhere eg on Internet2 and CANARIE
• There are a number of tools for helping to understand node and inter-node characteristics:
  • SWORD
    http://www.cs.berkeley.edu/~davidopp/sword/
  • All-Pair Pings
    http://www.pdos.lcs.mit.edu/~strib/pl_app/
  • CoMon
    http://comon.cs.princeton.edu/
  • IPerf
    http://jabber.services.planet-lab.org/php/iperf/