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1 . Use ping to determine the propagation delay. Specifically, send 10 very small packets (these will be 24 bytes) to a particular destination and recod the average round-trip time (RTT). Then use ping to send 10 packets with larger payload (type "ping" then press enter for help with ping) and compute the average RTT. Compare the difference in the RTTs and determine the transmission time. You might need to try this with various sized packets.
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2 . Do links have time-varying delay? To answer this questions run trace route and ping at different times of the day (e.g., the middle of the night, morning, afternoon, etc., or maybe just run ping for an entire day) and compare the delay times. (Make sure to include destinations not in the US. Also, use IP addresses instead of names. Use nslookup to translate between names an IP addresses.) Use packet sizes less than 1450. One way to do this is use "ping XXXX.com -t > PingData.txt." Then open the file in a text editor to remove the first few lines and last few lines and remove the letters "ms" (use the replace function for this). So, when you are done, the file has many lines of
...
Reply from 66.218.71.198: bytes=32 time=79 TTL=243
Reply from 66.218.71.198: bytes=32 time=80 TTL=243
...
Then open this file in excel (or matlab) and make a plot of RTT.
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