Direct Code Execution (DCE) is a module for ns-3 that provides facilities to execute, within ns-3, existing implementations of userspace and kernelspace network protocols or applications without source code changes. For example instead of using the pseudo application provided by ns-3 V4PingHelper you can use the true ping.

If you wish to cite DCE in your academic work, please reference this paper.


DCE is maintained by Hajime Tazaki and Matthieu Coudron.

Manual Structure

This document consists of the following parts:

  1. Quick Start: The document describes a quick instruction of DCE.
  2. User’s Guide: The document is for people who will use DCE to experiment.

DCE Outlook

  • To run an application using DCE, it is usually not necessary to change its sources. However you will need to recompile them.
  • The simulation is executed wholly within a single process which greatly facilitates the debugging.
  • DCE is very memory-efficient, thanks to the way it loads the executables similarly to shared libraries.

Supported Features

  • Simulation with POSIX socket application (no manual modifications)
  • C/C++ applications
  • Simulation with Linux kernel implemented network protocol
  • IPv4/IPv6
  • running with POSIX socket applications and ns-3 socket applications
  • configuration via sysctl-like interface
  • multiple nodes debugging with single gdb interface
  • memory analysis by single valgrind execution with multiple nodes
  • Variance of network stacks
  • ns-3 native stack (IPv4/IPv6, partially)
  • Network simulation cradle network stack (IPv4 TCP only)
  • Linux network stack (IPv4/IPv6/others)
  • Per-node configuration/stdin input
  • Per-node syslog/stdout/stderr files output

Tested Applications

  • CCNx
  • Quagga
  • iperf
  • ping/ping6
  • ip (iproute2 package)
  • Mobilt IPv6 daemon (umip)
  • Linux kernel (from 2.6.36 to 3.7 versions)
  • http server (thttpd)
  • torrent (libtorrent from rasterbar + opentracker)

Tested Environment

Currently, DCE only supports Linux-based operating systems. DCE has been tested on the following distributions:

  • Ubuntu 16.04 and equivalents (gcc-5.4, libc-2.23)

but you can try on others (e.g., CentOS, RHEL). However, unfortunately only a narrow range of older Linux systems work with DCE (gcc-5-based systems such as Ubuntu 16.04).

If you find that you can run on another distribution, please let the Maintainers know. Also, if you would like to work on getting DCE to work on newer systems, please let the Maintainers know.