Network use has evolved over time to be dominated by content distribution and retrieval, while networking technology is mainly concerned with connections between named hosts. Accessing contents and services require the mapping of what users care about to where the content is located. Content Centric Networking (CCN) is a new paradigm in networking and a future Internet architecture which treats content as the primitive - decoupling location from identity, security and access - to retrieve content by name.

inbaverSim is an OMNeT++ based model framework to simulate CCN based networks. The functionality and the message formats follow the description provided in RFC 8569 and RFC 8609. An overview to the model framework is provided in the publication inbaverSim: An OMNeT++ Model Framework for Content Centric Networking

The sections that follow provide details of inbaverSim such as installing, node architecture, etc. The text immediately below is a TL;DR summary of how to install and run simulations with inbaverSim.

1. Install the latest version of OMNeT++
2. Run the OMNeT++ IDE and install the INET model framework
3. Build the INET model framework in mode
4. Import inbaverSim repository (this respository) by cloning from GitHub inbaverSim
5. Build inbaverSim project
6. Run simulations using the omnetpp-simple-network.ini

Node Models

inbaverSim is able to model the operation of different types of CCN nodes and networks. A list of node types are given below.

• Wireless Nodes - Nodes that are able to connect to infrastructure based wireless networks (e.g., WLAN, LTE)
• Wireless Access Routers - Routers that are access points/base stations for wireless nodes
• DTN/OppNets Nodes - Wireless nodes that employ direct communications between nodes
• Wired Nodes - Nodes connected to networks over wired network attachments
• Access Routers - Routers for wired network nodes
• Core Routers - Central CCN routers that connect other networks
• Content Servers - Servers that host content
• Wireless Sensor Nodes - Wireless sensor nodes deployed with sensors (temperature, humidity, etc.)
• IOT Gateways - Gateways connecting wireless sensor networks and the Internet
• Internet - Node simulating a CCN based Internet where the behaviour of many nodes and applications are deployed

The picture below shows the topology of a CCN network with all the above nodes.

Protocol Stack

The node architecture of an inbaverSim node of any type consist of a 3-layer protoclol stack as seen from the following picture.

• Application: All CCN based applications are deployed at this layer
• Forwarding: The fowarding mechanism described in RFC 8569 or other custom CCN forwarding mechanism is implemented at this layer (e.g., DTN, IoT)
• Transport: This layer implements different transports that connect nodes to deliver CCN packets. Currently, two transports are supported - conceptual wired and wireless transports

The picture below shows the inbaverSim node model architecture in OMNeT++.

Installing

inbaverSim is written for OMNeT++ and additionally uses the INET model framework of OMNeT++. Therefore, they have to be installed first to use inbaverSim. The installation procedure is as follows.

1. Install OMNeT++ - OMNeT provides an Install Guilde to install OMNeT++ in different operating systems.

2. Install INET Model Framework - Installing is done through the OMNeT++ IDE. The steps are as follows.

• Run the OMNeT++ IDE
• Create a new workspace
• After creating the workspace, the IDE will prompt asking to install INET
• Once the INET code base is installed, rebuild INET in release mode

3. Install inbaverSim and build as follows.

• Import the code from the GitHub repositorty
• Adjust project properties (Project References and C/C++ General->Paths and Symbols)
• Build inbaverSim

If there are problems when building the model, check FAQ

Running Simulations

The simulation folder has sample .ini files to run simulations. The procedure of running a simulation is given below.

1. Setup the '.ini file to run simulations as follows.

• Select a sample .ini file from simulations folder
• Open file by double clicking
• Add/adjust parameters as required (e.g., change sim-time-limit to a different duration)

2. Run the simulation as follows.

• Select .ini file
• Right-click and click on Run As->OMNeT++ Simulation
• Select the Config name in the new window that will pop up
• Select the Run button to run the simulation

The pictures below shows two different CCN networks created to simulate.The first picture shows a simple CCN network that includes wireless and wired nodes connected to a network with CCN infrastructure (routers and content servers)

The second network is similar to the first one but with connections to CCN based sensor networks.

Statistics

Every simulation creates statistics during the simulation run. These statistics are collected in the simulations/results folder. Use the results viewing capability of the OMNeT++ IDE to view the results.

The graph below shows the content download delays of a single node during a 48-hour period.

The graph below shows the network-wide cache hit ratio during a 48-hour period.

Details about each statistic is listed in STATS.

Questions and Comments

If you have any questions or comments about inbaverSim, write to us at [email protected]