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1. path and round trip time measurements

1.1 project focus

1.2 why not one-way trip time measurements?

1.3 measurement methodology

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        creation: 06/05/1998 02:28:47 (0x3577901f)

        Src:     (0x32ed4cc)
        Dst:       (0x10160c6)
        Rtt: 83.134 ms
        HopDistance: 18 (0x12)
        IsComplete: true
        NumHops: 17 (0x11)
                HopNum:   1 IpAddr:    (0x12ed4cc)
                HopNum:   2 IpAddr:   (0xd2dd4cc)
                HopNum:   3 IpAddr:    (0x134eecd)
                HopNum:   4 IpAddr:  (0x9538eecd)
                HopNum:   5 IpAddr:   (0x1538eecd)
                HopNum:   6 IpAddr:  (0x6e38eecd)
                HopNum:   7 IpAddr:  (0x7238eecd)
                HopNum:   8 IpAddr:  (0x7e38eecd)
                HopNum:   9 IpAddr:      (0x90146cc)
                HopNum:  10 IpAddr:    (0xcd0446cc)
                HopNum:  11 IpAddr:     (0x5d0146cc)
                HopNum:  12 IpAddr:     (0x540346cc)
                HopNum:  13 IpAddr:  (0x7ab946cc)
                HopNum:  14 IpAddr: (0x8deecfcd)
                HopNum:  15 IpAddr:   (0x663744c0)
                HopNum:  16 IpAddr:   (0xc0fb982)
                HopNum:  17 IpAddr:   (0xa201b982)

1.4 initial observations (hop distance distribution)

1.5 initial observations (frequency of IP addresses in paths)

key routers play huge role in global connectivity from a given source

example, measured from CAIDA in San Diego (Aug 21, 1998):

note log-log scale

1.6 observations: visible outdegree (indicates many next hops/peerings)

from San Diego

         IP address          outdegree
         -----------------   ---------               70              65                61              55               54               50              41              36              35              34               32              32               30


1.7 scope of CAIDA measurements (12 mo projection)

1.8 architecture

1.9 visualization efforts skping: real-time single destination RTT measurement/display

skpath: real-time single @@dwm path dynamics monitor

skpath to

1.10 data visualization: RTT candle plots

historical order statistics in candle plots (aggregation of large datasets)

NOTE: heavy-tailed distributions.

1.11 Cisco with prefix cache

skping: real-time single destination RTT measurement/display

1.12 Cisco running CEF

1.13 data viz: RTT candle plots, to aggregate larger data sets

simple forward path analysis

the naive approach taken by some tools can be misleading....

NOTE: you can do both, but presumably you'll want to know the difference in the paths and should hence just add the hops as individual targets which are measured in the same manner as the final destination.

1.14 further RTT visualizations

1.15 macroscopic topology visualization

1.16 next steps

22 aug 98, kc,

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