This is an NDN application designed to investigate the difference in travel times for interest packets in relation to data packets. The files should be put in the ndn-cxx/examples directory and can be built using the instructions found at: https://github.com/named-data/ndn-cxx/tree/master/examples.

To use, start Server A on one machine:

# From the ndn-cxx directory on Machine A
./build/examples/serverA [prefix Server A will advertise]

and start Server B on the other machine:

# From the ndn-cxx directory on Machine B
./build/examples/serverA [prefix Server B will advertise] [name of Interest 2]

Note that [name of Interest 2] should begin with the same prefix that Server A is advertising. For example, if Server A is advertising /serverA, [name of Interest 2] could be /serverA/interest2. Then, on the same machine as server A, start the ping client:

# From the ndn-cxx directory on Machine A
./build/examples/startDoublePing [name of Interest 1] [number of interests to send]

Note that [name of Interest 1] should begin with the same prefix that Server B is advertising. For example, if Server B is advertising /serverB, [name to ping] could be /serverB/interest1.

startDoublePing will complete [number of interests to send] double ping cycles and then display the following statistics:

• Interest RTT
• Generate Interest 2 Time
• Interest Travel Time
• Data RTT
• Generate Data 1 Time
• Data Travel Time

The Generate Data 1 Time is fairly signifcant in some cases, as signing a data packet at runtime takes ~4 ms. To combat this, the code includes an option to make and sign 100 data packets in advance. The necessary lines of code are currently commented out and can be found by searching for *** V2 *** in the startDoublePing.cpp and serverB.cpp files.

This code has been adapted from the ndn-cxx consumer and producer applications (https://github.com/named-data/ndn-cxx/tree/master/examples), as well as the ndn-tools implementation of ndnping (https://github.com/named-data/ndn-tools/tree/master/tools/ping).