= [../Setup Understanding the AM API using Named Data Networking] = {{{ #!html
Image Map
}}} == 4 Wait for resources to be ready == You can tell whether your nodes are ''ready'' by using a script built on `omni` called `readyToLogin`. {{{ #!html
  1. Please use the command:
     
    readyToLogin -a AM_NICKNAME LabOne 
    
     
    where (as before) AM_NICKNAME and LabOne are your aggregate 
    manager nickname and your slice name (both found on your worksheet). 
      
  2. If it reports that the sliver is not yet ready (for example, it might say that the status is "changing"), then wait a minute or two and try again. Once everything is complete, readyToLogin will give output that should look something like this:
     
    ... 
    rschr's geni_status is: ready (am_status:ready)  
    User example logs in to rschr using: 
            ssh  -p 32768 -i /Users/example/.ssh/geni_key_portal example@pc1.utah.geniracks.net 
    User example logs in to collar using: 
            ssh -p 32769 -i /Users/example/.ssh/geni_key_portal example@pc1.utah.geniracks.net 
    ... 
    
}}} == 5 Trying out the NDN application == In this experiment, you will be able to see the NDN in-network caching in action. Our experiment consists of the following nodes: * A data source node, called {{{Custodian}}} that holds data in the namespace /nytimes * A internet router node, called {{{Internet}}} that forwards {{{Interest}}} and {{{Data}}} packets to and from the {{{Custodian}}}. * A university hub node, called {{{University}}} that forwards {{{Interest}}} and {{{Data}}} packets to and from the university nodes. * A principal investigator node, called {{{PI}}} and a experimenter node, called {{{Experimenter}}} that will send {{{Interest}}} requests to the {{{Custodian}}} via UDP tunnels. Download the scripts and Python codes to your computer and extract it. * [http://192.1.242.151/files/ndn-tutorial.gz ndn-tutorial.gz] Or alternatively, {{{ $ wget http://192.1.242.151/files/ndn-tutorial.gz $ tar -xvf ndn-tutorial.gz }}} In the '''ndn-tutorial-config.sh''' configuration file, edit the fields according to your GENI username, SSH key, GENI Aggregate name, pc and port numbers. Keep the quotes format unchanged, otherwise the script may not run. Run {{{copy-scripts.sh}}}, this will automatically transfer the necessary files to the nodes in our topology. {{{ $ ./copy-scripts.sh }}} Login into the node {{{Custodian}}} and start the NDN Forwarding Daemon (NFD), {{{ $ nfd-start }}} wait until the shell prompt returns (~ a few seconds). The NFD is now up and running. === 5.1 Run the NDN application on the same node === You are now ready to start the producer application and register a namespace. ^([#hn note: you can try other namespaces as well])^ {{{ $ python producer.py -n /nytimes }}} You should see a message {{{ $ Registering prefix /nytimes }}} Open another terminal on the custodian node and run {{{ $ python consumer.py -u /nytimes/science }}} This will start the consumer application that will send Interest request packets to the producer. Take a moment to look at the entries in the NFD. You are all set. Stop the producer application by {{{Ctrl + C}}} and stop the NFD {{{ $ nfd-stop }}} === 5.2 Run the NDN application on the entire topology === For this section, we are going to start the NFD in all nodes and register the namespace. We automated these tasks for the {{{University}}} and {{{Internet}}} nodes using a script. On your computer, run {{{ $ ./setup-app.sh }}} You should see NFD being started on the nodes. SSH to the {{{Custodian}}} node and start the {{{producer}}} application {{{ $ nfd-start $ python producer.py -n /nytimes }}} SSH to the {{{Experimenter}}} node, register the namespace, and start the {{{consumer}}} application {{{ $ nfdc register / udp4://10.0.0.1 $ python consumer.py -u /nytimes/science }}} This time the {{{Interest}}} request travels the entire topology, leaving breadcrumbs. The {{{Data}}} packet follows the breadcrumbs back to the {{{consumer}}}, leaving cached versions of the content. This is call in-network caching and it is one of the most important features in {{{Information Centric Networking (ICN)}}} You can check this phenomenon by running the same consumer application in the {{{PI}}} node. SSH to the {{{PI}}} node, register the namespace, and start the {{{consumer}}} application {{{ $ nfdc register / udp4://10.0.0.1 $ python consumer.py -u /nytimes/science }}} This time your {{{PI}}} node gets the content back, but nothing happens on the {{{Custodian}}} because the requested content is cached in the {{{University}}} node. You can repeat the experiment with different namespaces {{{ $ python consumer.py -u /nytimes/math }}} === 5.3 (Optional) Visualize experiment data flows === To use the GENI Desktop to visualize the data flows in your network, continue with the instructions [wiki:GENIExperimenter/Tutorials/GettingStarted_PartII_ccn/Procedure/Execute/GEMINI here]. ---- = [wiki:GENIExperimenter/Tutorials/jacks/GettingStarted_PartII_ndn/Procedure/Setup Setup] = = [wiki:GENIExperimenter/Tutorials/jacks/GettingStarted_PartII_ndn/Procedure/Finish Next: Finish] =