1. Jungsik Yoon jsyoon@nm.gist.ac.kr Networked Media Lab Department of Information and Communication Gwangju Institute of Science and Technology (GIST) 2009. 9. 7

2.  It is planned to develop mobility emulation function in our TB at the third year.  I will introduce previous mobility emulators and its practical usage.  Finally, I will explain HY’s work in OMF and how to adapt that works in our TB (in GMF)

3.  Mobility Emulator? ◦ Study the Human mobility or behavior of the modern wireless mobile ad-hoc network (MANET) systems such as a delay (or disruption) tolerant network (DTN) and its application is a challenging task. ◦ Most of Previous research of human mobility was studied using network simulator. To test in real experiment, it requires a lot of investment for management as well as setup cost.  Advantages of emulation for studying of mobility ◦ Multipath fading ◦ Relative path delay ◦ Doppler or frequency shift

4.  Target environment ◦ The ORBIT indoor testbed, comprising of 128 IEEE 802.11 a/b/g interfaces, attached to 64 stationary nodes, arranged in an 8 by 8 grid ◦ Use video streaming application  Issues ◦ How to emulate real mobility information? ◦ How to develop handoff function for node’s mobility  Purpose of research ◦ CSMA/CA performance as the number of Tx nodes increasing ◦ Inter-contact time & user mobility ◦ WLAN hand-off mechanisms

5.  Input human mobility  Emulated path of a moving nodes. (if distance is large, utilize noise generation system)  Target application is working on virtual machine and it is connected to real node through tunneling in Network layer.

6.  Motivation ◦ tunneling and spatial switching methods are not favorable to study DTN and modern MANET applications because it is hard to emulate the behavior of network stack below IP layer. ◦ On/Off-based mobility emulation method and its implementation that virtually migrates applications over static-grid testbed to mimic the device mobility  System Design ◦ Emulator server is communica -te with each client throught wired connections