model: New content store variations: support for content freshness
The following content store realizations now fully support freshness set
in ContentObjects:
- ns3::ndn::cs::Freshness::Lru
- ns3::ndn::cs::Freshness::Random
- ns3::ndn::cs::Freshness::Fifo
Example ndn-simple-with-content-freshness demonstrates basics of new
content stores.
diff --git a/examples/ndn-simple-with-content-freshness.cc b/examples/ndn-simple-with-content-freshness.cc
new file mode 100644
index 0000000..cefb232
--- /dev/null
+++ b/examples/ndn-simple-with-content-freshness.cc
@@ -0,0 +1,118 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2012 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+// ndn-simple.cc
+#include "ns3/core-module.h"
+#include "ns3/network-module.h"
+#include "ns3/point-to-point-module.h"
+#include "ns3/ndnSIM-module.h"
+
+using namespace ns3;
+
+/**
+ * This scenario simulates a very simple network topology:
+ *
+ *
+ * +----------+ 1Mbps +--------+ 1Mbps +----------+
+ * | consumer | <------------> | router | <------------> | producer |
+ * +----------+ 10ms +--------+ 10ms +----------+
+ *
+ * This scenario demonstrates how to use content store that responds to Freshness parameter set in ContentObjects.
+ * That is, if producer set Freshness field to 2 seconds, the corresponding content object will not be cached
+ * more than 2 seconds (can be cached for a shorter time, if entry is evicted earlier)
+ *
+ * NS_LOG=DumbRequester ./waf --run ndn-simple-with-content-freshness
+ */
+
+int
+main (int argc, char *argv[])
+{
+ // setting default parameters for PointToPoint links and channels
+ Config::SetDefault ("ns3::PointToPointNetDevice::DataRate", StringValue ("1Mbps"));
+ Config::SetDefault ("ns3::PointToPointChannel::Delay", StringValue ("10ms"));
+ Config::SetDefault ("ns3::DropTailQueue::MaxPackets", StringValue ("20"));
+
+ // Read optional command-line parameters (e.g., enable visualizer with ./waf --run=<> --visualize
+ CommandLine cmd;
+ cmd.Parse (argc, argv);
+
+ // Creating nodes
+ NodeContainer nodes;
+ nodes.Create (3);
+
+ // Connecting nodes using two links
+ PointToPointHelper p2p;
+ p2p.Install (nodes.Get (0), nodes.Get (1));
+ p2p.Install (nodes.Get (1), nodes.Get (2));
+
+ // Install CCNx stack on all nodes
+ ndn::StackHelper ccnxHelper;
+ ccnxHelper.SetDefaultRoutes (true);
+ ccnxHelper.SetContentStore ("ns3::ndn::cs::Freshness::Lru",
+ "MaxSize", "2"); // allow just 2 entries to be cached
+ ccnxHelper.InstallAll ();
+
+ // Installing applications
+
+ // Consumer
+ ndn::AppHelper consumerHelper ("DumbRequester");
+
+ // /*
+ // 1) at time 1 second requests Data from a producer that does not specify freshness
+ // 2) at time 10 seconds requests the same Data packet as client 1
+
+ // 3) at time 2 seconds requests Data from a producer that specifies freshness set to 2 seconds
+ // 4) at time 12 seconds requests the same Data packet as client 3
+
+ // Expectation:
+ // Interests from 1, 3 and 4 will reach producers
+ // Interset from 2 will be served from cache
+ // */
+
+ ApplicationContainer apps;
+
+ consumerHelper.SetPrefix ("/no-freshness");
+ apps = consumerHelper.Install (nodes.Get (0));
+ apps.Start (Seconds (0.1));
+ apps.Stop (Seconds (10.0));
+
+ consumerHelper.SetPrefix ("/with-freshness");
+ apps = consumerHelper.Install (nodes.Get (0));
+ apps.Start (Seconds (20.1));
+ apps.Stop (Seconds (30.0));
+
+ // Producer
+ ndn::AppHelper producerHelper ("ns3::ndn::Producer");
+ producerHelper.SetAttribute ("PayloadSize", StringValue("1024"));
+
+ producerHelper.SetAttribute ("Freshness", TimeValue (Seconds (0))); // unlimited freshness
+ producerHelper.SetPrefix ("/no-freshness");
+ producerHelper.Install (nodes.Get (2)); // last node
+
+ producerHelper.SetAttribute ("Freshness", TimeValue (Seconds (2.0))); // freshness 2 seconds (!!! freshness granularity is 1 seconds !!!)
+ producerHelper.SetPrefix ("/with-freshness");
+ producerHelper.Install (nodes.Get (2)); // last node
+
+ Simulator::Stop (Seconds (30.0));
+
+ Simulator::Run ();
+ Simulator::Destroy ();
+
+ return 0;
+}