Exercise 2: Measuring Performance of a MobilityFirst Router ¶

Objective ¶

In this exercise, we will try to drive synthetic traffic through the router and measure key performance characteristics such as throughput and forwarding latency. Since MobilityFirst presents a hop-by-hop block data transport, we can vary the unit size of the data block and observe it's impact on the performance. We will also try to visualize the performance results using OMF's result service by installing an OML-enabled monitor on the routers.

Deploy the Network ¶

This tutorial assumes that a 4 nodes topology has been already established in one of the Orbit sandboxes or the grid:

Host (GUID 101) ---- MFR1 (GUID 1) ---- MFR2 (GUID 2) ---- Host2 (GUID 102)

If not coming from the previous exercise follow these instructions to setup your network

Once logged into the grid console:

ssh username@console.grid.orbit-lab.org

From the console we will start by loading the Mobilityfirst image into the four nodes that have been assigned to you:

omf load -i 'mf-release-latest.ndz' -t system:topo:mf-groupX

system:topo:mf-groupX represents the group of 4 nodes and mf-groupX has to be replaced by the group id assigned to you.

For example, mf-group1 will load the image on nodes 'node1-1,node1-2,node2-1,node2-2'

If the output of your console looks similar to:

INFO exp:  ----------------------------- 
 INFO exp:  Imaging Process Done 
 INFO exp:  4 nodes successfully imaged - Topology saved in '/tmp/pxe_slice-2014-10-15t02.10.16.594-04.00-topo-success.rb'
 INFO exp:  ----------------------------- 
 INFO EXPERIMENT_DONE: Event triggered. Starting the associated tasks.
 INFO NodeHandler: 
 INFO NodeHandler: Shutting down experiment, please wait...
 INFO NodeHandler: 
 INFO NodeHandler: Shutdown flag is set - Turning Off the resources
 INFO run: Experiment pxe_slice-2014-10-15t02.10.16.594-04.00 finished after 1:50

your nodes have been imaged correctly.

Deploy Network ¶

Software and experiment control in the ORBIT testbed can be automated greatly using the OMF framework. An OMF control script is written in Ruby and allows the experimenter to specify the set of nodes, their network configuration, to specify software components and arguments, and to control their execution on one or more nodes. We will use an OMF script to bring up 4 ORBIT nodes to host our topology, with corresponding software components.

We will first introduce the main details of the scripts that will be run and then will step to the execution itself.

Software Component Specification ¶

The following snippet shows the specification of the MobilityFirst router along with the required arguments:

defApplication('MF-Router', 'router') {|app|
    app.shortDescription = "Click-based MobilityFirst Access Router"
    app.path = "/usr/local/src/mobilityfirst/eval/orbit/tutorial/scripts/ARWrapper.sh" 
    # click options
    app.defProperty('num_threads', 'number of threads', "-t",{:type => :integer, :mandatory => true, :default => 4, :order => 1})
    app.defProperty('ctrl_port', 'port for Click control socket', "-c",{:type => :integer, :order => 2})
    # click config file 
    app.defProperty('config_file', 'Click configuration file', "-C",{:type => :string,:mandatory=> true})
    # keyword parameters used in click config file
    app.defProperty('my_GUID', 'router GUID', "-m",{:type => :string, :mandatory => true})
    app.defProperty('topo_file', 'path to topology file', "-f",{:type => :string, :mandatory => true})
    app.defProperty('core_dev', 'core network interface', "-d",{:type => :string,:mandatory => true})
    app.defProperty('GNRS_server_ip', 'IP of local GNRS server', "-s",{:type => :string,:mandatory => true})
    app.defProperty('GNRS_server_port', 'Port of GNRS server', "-p",{:type => :string,:mandatory => true})
    app.defProperty('GNRS_listen_ip', 'IP to listen for GNRS response', "-i",{:type => :string,:default => "0.0.0.0"})
    app.defProperty('GNRS_listen_port', 'port to listen for GNRS response', "-P",{:type => :string,:default => "10001"})
    app.defProperty('edge_dev', 'edge network interface', "-D",{:type => :string,:mandatory => true})
    app.defProperty('edge_dev_ip', 'IP assigned to edge interface', "-I",{:type => :string,:mandatory => true})
}

defApplication('MF-GNRS', 'gnrs') {|app|
    app.shortDescription = "GNRS Server"
    app.path = "/usr/local/src/mobilityfirst/eval/orbit/tutorial/scripts/GNRSWrapper.sh" 
    app.defProperty('log4j_config_file', 'log 4j configuration file', "-d",{:type => :string, :order => 1})
    app.defProperty('jar_file', 'server jar file with all dependencies', "-j" ,{:type => :string, :mandatory=> true, :default => "/usr/local/src/mobilityfirst/gnrs/jserver/target/gnrs-server-1.0.0-SNAPSHOT-jar-with-dependencies.jar", :order => 2})
    app.defProperty('config_file', 'server configuration file', "-c",{:type => :string, :mandatory=> true, :order => 3})
}

#Enable OML reporting by default
defApplication('MF-HostStack', 'hoststack') {|app|
    app.shortDescription = "MF host network stack"
    app.path = "/usr/local/bin/mfstack" 
    app.defProperty('log_level', 'log level', nil,{:type => :string, :mandatory => true, :order => 1, :default => "-e"}) # default is 'error'
    app.defProperty('config_file', 'stack configuration file', nil,{:type => :string, :mandatory => true, :order => 2})
}

As seen above, the router is configured with both 'core' and 'edge' interfaces. The core interfaces connect routers towards the core of the network, while the edge interface enables hosts to connect and access the MobilityFirst network.

Also seen above is the GNRS service related arguments that specify which server (IP and port) the router should use for in-network name resolution purpose, both for sending requests and to receive responses. By default it will listen on all interfaces and port 10001.

Setting up the Software Node Groups ¶

The following shows how the node groups for the routers are setup in the OMF control scripts. Node groups allows experimenters to use single statements to set configuration and execute commands across all nodes in the group.

for i in 1..num_routers
    defTopology("topo:router_#{i}") { |t|
        aNode = routersTopo.getNodeByIndex(i-1)
        t.addNode(aNode)
        info aNode, " assigned role of router with GUID: #{i}"
    }
  
    defGroup("router_#{i}", "topo:router_#{i}") {|node|
        node.addApplication('MF-Router') {|app|
            app.setProperty('num_threads', router_threads)
            app.setProperty('config_file', click_conf)
            app.setProperty('my_GUID', router_guid[i-1])
            app.setProperty('topo_file', rtr_topo_file)
            app.setProperty('core_dev', core_dev)
            app.setProperty('GNRS_server_ip', GNRS_server_ip)
            app.setProperty('GNRS_server_port', GNRS_server_port)
            app.setProperty('GNRS_listen_ip', "192.168.100.#{i}")
            app.setProperty('GNRS_listen_port', GNRS_listen_port)
            app.setProperty('edge_dev', edge_dev)
            app.setProperty('edge_dev_ip', router_ether_if_ip[i-1])
        }

      #If is the first router add the GNRS
      if i == 1
      aNode = routersTopo.getNodeByIndex(i-1)
      info aNode, " will also host the GNRS server"
          node.addApplication('MF-GNRS') {|app|
            app.setProperty('log4j_config_file', GNRS_log_file)
            app.setProperty('jar_file', GNRS_jar_file)
            app.setProperty('config_file', GNRS_conf_file)
          }
      end
    
      node.net.e0.ip = "192.168.100.#{i}"
      node.net.e0.netmask = '255.255.255.0'
    
    node.net.w0.mode = "adhoc"
    node.net.w0.type = 'g'
    node.net.w0.channel = "11"
    node.net.w0.essid = "SSID_group_#{i}"
    node.net.w0.ip = "192.168.#{i}.1"
    }
end

#Create host groups
for i in 1..num_hosts
    defTopology("topo:host_#{i}") { |t|
        aNode = hostsTopo.getNodeByIndex(i-1)
        t.addNode(aNode)
        info aNode, " assigned role of client with GUID: #{100 + i}"
    }
  
    defGroup("host_#{i}", "topo:host_#{i}") {|node|
        node.addApplication('MF-HostStack') {|app|
            app.setProperty('config_file', hoststack_conf_file[i-1])
            app.setProperty('log_level', log_level)
        }
      
    #node.net.e0.ip = "192.168.#{i}.#{i+100}"
      #node.net.e0.netmask = '255.255.255.0'
    
    node.net.w0.mode = "adhoc"
    node.net.w0.type = 'g'
    node.net.w0.channel = "11"
    node.net.w0.essid = "SSID_group_#{i}"
    node.net.w0.ip = "192.168.#{i}.2"
    }
end

As can be seen above, properties which were defined in the MF-Router, MF-GNRS and MF-HostStack applications have been set here. Moreover, node interfaces have been set up, and IP addresses have been assigned to them. As we discussed earlier the router is configured with both edge and core interfaces. The ethernet interface is used to connect to the core of the network, and the wireless interface is for connection to the clients. On the other side, the client is equipped with wifi interface to connect to the access router.

We will assume the network described and initialized in Exercise 1 is up and functional. Here also we will use mfping to send packets between the hosts. In addition to the deployment specified in exercise 1, we install OML-enabled statistics monitor for MobilityFirst routers.

The entire script is available as part of the tutorial package as orbit/tutorial/scripts/exercise2.rb

The key extensions over previous script are briefly discussed below.

Setting up the 'OML enabled Monitor on Routers Application' ¶

The following snippet from the script shows the code added to set up the OML enabled Monitor on Routers Application and its arguments:

defApplication("mf_click_monitor", "mf_click_monitor") do |app|
    app.shortDescription = "OML enabld statistics monitor for MobilityFirst Routers"
    app.path = "/usr/local/bin/mf_click_mon"
    app.defProperty('ctrl_port', 'Port for Click control socket', nil,{:type => :string, :mandatory => true, :order => 1})
    app.defProperty('self-id', 'OML ID', nil,{:type => :string, :mandatory => true, :order => 2})
    app.defProperty('oml-config-file', 'OML configuration file', "--oml-config",{:type => :string,:mandatory=> true})
    app.defProperty('oml-domain', 'OML domain name', "--oml-domain",{:type => :string,:mandatory=> true})
end

self_id = "MonitorID"
oml_config_file = "/usr/local/src/mobilityfirst/eval/orbit/tutorial/conf/click-oml-config.xml"
oml_domain = "#{Experiment.ID}"

defGroup("router_monitors", "router_universe") {|node|
  node.addApplication('mf_click_monitor') {|app|
    app.setProperty('ctrl_port', router_control_port)
    app.setProperty('self-id', self_id)
    app.setProperty('oml-config-file', oml_config_file)
    app.setProperty('oml-domain', oml_domain)
  }
}

As seen above, the OML enabled monitor will work with the MobilityFirst router that will enable us to track and visualize the forwarding performance of MFRs. In order report statistics to the OML server, the monitor periodically queries the monitor through the control port (ctrl_port in our script)

Running the Benchmark Application ¶

To generate the traffic that will be reported by the routers, we will use the same mfping application as in the previous exercise.

First of all, you will need to start the experiment via the OMF script. Download the script to the orbit console:

    wget www.winlab.rutgers.edu/~bronzino/downloads/orbit/exercise2.rb

Once the file has been downloaded, execute it with the following command:

    omf exec exercise2.rb

The following snippet shows how the exercise runs. As indicated above first we will run mfping between the hosts as described in exercise 1:

If not coming from the previous exercise follow these instructions to run mfping

Once the host and router components are up, you can log in to the sender (host identified by GUID 101) and receiver (host identified by GUID 102) host nodes (two separate terminals) and run the 'mfping' application.

Run the mfping 'server' specifying the application GUID:

mfping -s -m 102 -o 101

where "-s" specifies that the host is running as server, "-m" specifies the source guid and "-o" the destination one

To run the mfping 'client'

mfping -c -m 101 -o 102 -n 10

Where "-c" specifies the client is running and "-n" specifies the number of pings between the two nodes. If successfully executed, the client will display some information similar to the following snippet

root@node1-1:~# mfping -c -m 101 -o 102 -n 10
64 bytes received: seq_n=0, time=25.1470 msec
64 bytes received: seq_n=1, time=23.7070 msec
64 bytes received: seq_n=2, time=20.0559 msec
64 bytes received: seq_n=3, time=24.0371 msec
64 bytes received: seq_n=4, time=23.1831 msec
64 bytes received: seq_n=5, time=20.3069 msec
64 bytes received: seq_n=6, time=24.1379 msec
64 bytes received: seq_n=7, time=19.6230 msec
64 bytes received: seq_n=8, time=20.3931 msec
64 bytes received: seq_n=9, time=20.2239 msec

Visualizing the Performance Data ¶

Method 1: OMF framework supports a result service that allows experimenters to query data stored using the OML measurement framework. The query is performed over the web and requires that you know the hostname and port where the result service runs, and the experiment ID associated with this experiment - this is obtained from the output following the execution of the control script. It should look something like this :

Experiment ID: default_slice-2014-10-15t02.12.19.869-04.00

The result service supports either dumping of the entire database or a SQL-like querying option to selectively retrieve required measurement data. The below HTTP request shows an example query to retrieve the reported statistics from the OML enabled monitor for MobilityFirst Routers. In order to see the results the following web page should be retrieved using any browser. The following URL should be typed in the browser:

http://oml.orbit-lab.org:5054/result/dumpDatabase?expID=default_slice-2014-10-15t02.12.19.869-04.00

In this case the hostname is "oml.orbit-lab.org" and the port number is "5054".

Note that the URL used in wget, in particular the arguments, may require to be encoded to unambiguously represent special characters when using the HTTP protocol.

This data can also be downloaded using "wget" command and easily visualized using a tool such as gnuplot. You can find a helper script in the tutorial package that plots they key performance data downloaded.

Method 2: Alternatively, the performance data may be visualized using omf-web, OMF's web-based visualization service. It also works in concert with the result service referenced in Method 1, and makes available a variety of graph widgets to visualize live-experiment data logged using OML. Detailed documentation on the installation and usage of omf-web can be found on the ​omf-web github site.

Since this is installed on all ORBIT domains, we only need to concern ourselves with defining the widget configuration required to bring up the live graphs for the performance data we are logging. In order to bring up the visualization, we only need to start the basic omf-web service with the configuration file arguments.