Emulation Examples
==================

This folder contains various examples which connect the simulation with real
networks. There are two key components to do this. One is the called external
interface (ExtInterface) which represents the network interface in the simulation
towards the real network. The other is called the RealTimeScheduler which is
responsible for synchronizing the simulation time with real time.

In order to run any emulation example in this folder, INET must be compiled with
the "Network Emulation" feature enabled. Enabling this feature can be done using
the IDE / INET Project Properties / Project Features or the opp_featuretool. If
the "Network Emulation" feature is not enabled, the simulation will stop with a
'Class "inet::RealTimeScheduler" not found' error.

To compile INET with the "Network Emulation" feature enabled, make sure that
libpcap-dev (v1.5.3 or later) is installed on your machine.

In order to be able to send packets through raw sockets and to receive packets
through pcap, applications require special permissions. There are two ways to
achieve this under linux.

The suggested solution is to use setcap to set the application permissions:

$ sudo setcap cap_net_raw,cap_net_admin=eip $(which opp_run_dbg)
$ sudo setcap cap_net_raw,cap_net_admin=eip $(which opp_run_release

This solution makes running the examples from the IDE possible. Alternatively,
the application can be started with root privileges from command line:

$ sudo `inet_dbg -p -u Cmdenv`

In any case, it's generally a bad idea to start the IDE as superuser. Doing so
may silently change the file ownership for certain IDE configuraiton files, and
it may prevent the IDE to start up for the normal user afterwards.