Wireless Network Design: Optimization Models and Solution ...

12 Simulation-Based Methods for Network Design 287
IEEE802.16 wireless access technologies when the Host Identity Protocol (HIP)
[17] is used for managing mobility. HIP is an emerging end-to-end (e2e) security
association establishment and maintenance protocol that gathers security, multihoming,
and mobility management through the introduction of a new namespace in the
TCP/IP stack. Therefore, this case study focuses on analyzing the feasibility of HIP
when handovers take place. It provides insight into the mobility management protocol
selection not only for the research community, but also for network operators.
The OMNeT++ [20] simulation tool was selected for this study because of its
mature simulation model for HIP. OMNeT++ is an open source simulation platform
that provides a modular and extensible architecture for modeling any communication
context regardless its complexity. OMNeT++ does not provide specific components
to be included in the simulation scenario, but modules that can be hierarchically
combined to build specific network components. These modules are defined
based on a set of frameworks. A framework is a package that contains functions and
atomic modules to create different network functionalities and components. The
development of frameworks is independent to the core of the OMNeT++ simulation
tool. Consequently, customized modeling environments, that meet specific user
needs, can be developed through the integration of available frameworks.
In this case study, in order to study HIP protocol in a multi-technology mobile
environment, we built a new framework that integrates functionalities from two
different frameworks: Inetmanet [20] and HIPSim++ 3 . Inetmanet offers modules
for modeling IEEE802.11 and IEEE802.16 technologies as well as modules for
defining the mobility patterns of the mobile nodes, channel models, etc. On the
other hand, the HIPSim++ framework provides a basic model of the HIP protocol.
HIPSim++ has been specifically designed for modeling the HIP protocol based on
the xMIPV6 framework where fundamental functionalities for modeling mobility
management protocols are defined. The resultant integrated framework provides required
modules and functionalities to model IEEE802.11 and IEEE802.16 wireless
access technologies and handover processes managed with the HIP protocol. Figure
12.11 shows the main stages involved in the framework development to obtain the
customized framework.
Fig. 12.11 Framework Integration
3 The source code for HIPSim++ is available online at
http://www.ict-optimix.eu/index.php/HIPSim.