MUM Experimental Results

MUM Experimental Results

We have thoroughly tested and evaluated the performance of the MUM handoff management by deploying MUM streaming applications in our campus wireless network. Our testbed consists of several Windows and Linux client laptops equipped with four different wireless cards: i) in-ternal Intel PRO/Wireless 3945AGB, ii) Orinoco Gold Wi-Fi cards, iii) internal ASUS BT card, and iv) Mopogo BT dongles. MUM service gateways execute on standard Linux boxes with 1.8 GHz processors and 1024MB RAM.

During experiments, clients have moved between BT and Wi-Fi cells served respectively by Mopogo BT dongles and Cisco Aironet 1100 APs, by chang-ing various MUM WI domains corresponding to different buildings. All RSSI and handoff traces collected during our on-the-field experiments are available here. The following experimental results have been obtained while provisioning a video surveillance service consist-ing of a H263-encoded VoD flow (frame size = 176x144 pixels, constant frame rate = 8 frames/s) with buffer slots storing H263 RTP packets (667B per packet on the average).

Preliminary Results

Vertical Handoff Times

To initially assess the performance of the system, we evaluated main components that affect vertical handoff durations; in particular, we were interested to see how network coverage influenced handoff duration. Each measured time were evaluated on a set of 40 measures and we report mean value and standard deviation; each time is reported in seconds.

From Wi-Fi to BT: Target antenna	Network Coverage	Handoff latency (with BT inquiry)		Handoff latency (without BT inquiry)		Ignition time
		Mean	St.Dev.	Mean	St.Dev.	Mean	St.Dev.
Mopogo Broadcom chipset BT card	High (RSSI ~ 0, Goodput ~ 500-670 kbps)	6,727	0,707	1,553	0,250	0,044	0,002
Mopogo Broadcom chipset BT card	Low (-12<=RSSI <0, Goodput ~ 200-400 kbps)	9,207	0,699	3,633	0,438	0,044	0,002
Centrino Duo internal SRC chipset BT card	High (RSSI ~ 0, Goodput ~ 500-670 kbps)	6,921	0,647	1,765	0,239	0,047	0,002
Centrino Duo internal SRC chipset BT card	Low (-11<=RSSI<0 , Goodput ~ 200-400 kbps)	9,614	1,284	3,734	0,651	0,047	0,002
From BT to Wi-Fi: Target antenna	Network Coverage	Handoff time		AP detection time		Ignition time
Centrino Duo internal Wi-Fi card	High (RSSI>= -25, Goodput ~ 6,47 Mbps)	0,384	0,072	0,212	0,029	0,016	0,001
Centrino Duo internal Wi-Fi card	Low (RSSI <= -89, Goodput ~3,98 Mbps)	0,971	0,163	0,414	0,056	0,016	0,001
Orinoco Gold Wi-Fi card	High (RSSI>= -50, Goodput ~ 7 Mbps)	0,487	0,064	0,303	0,047	0,024	0,001
Orinoco Gold Wi-Fi card	Low (RSSI <= -80, Goodput ~1-2 Mbps)	0,584	0,067	0,267	0,047	0,024	0,001

Table 1: Vertical Handoff Times

We are currently updating this page.

More details will be available soon!!

2-feb-10