  With the proliferation of cheaper electronic devices, wireless communication
over multiple-channels in a multi-interface network is now possible. For
instace, wireless sensor nodes can now operate over multiplechannels. Moreover,
cognitive radio sensor networks are also evolving, which also operates over
multiple-channels. In the market, we can find antennas that can support the
operation of multiple channels, for e.g. the cc2420 antenna that is used for
communication between wireless sensor nodes consists of 16 programmable
channels. The proper utilization of multiple-channels reduces the interference
between the nodes and increase the network throughput. Recently, a Cognitive
Radio Cognitive Network (CRCN) patch for NS-2 simulator has proposed to support
multi-channel multi-interface capability in NS-2. In this tutorial, we consider
how to simulate a multi-channel multiinterface wireless network using the NS-2
simulator. This tutorial is trageted to the novice users who wants to
understand the implementation of multi-channel multi-interface in NS-2. We take
the Cognitive Radio Cognitive Network (CRCN) patch for NS-2 simulator and
demonstrate broadcasting over multiple-channels in a multi-interface network
setting. In our seeting, node braodcasts the Hello packets to its neighbors.
Neighboring nodes receive the Hello packets if and only if they are tuned to
the same channel. We demonstrate through example that the tuning of receivers
can be done in two fashions.
