Wireless Streaming Multimedia LaboratoryComputer Science Department
Worcester Polytechnic Institute
100 Institute Road
Worcester, MA 01609, USA
Streaming multimedia applications over wireless have been increasingly deployed. However, streaming multimedia techniques are primarily designed for wired networks and can perform poorly over wireless networks. Our research focuses on the impact of a wireless connection on the performance of streaming multimedia applications.
We have developed a wireless testbed for streaming multimedia research as shown in Figure 1. A server streams multimedia content over IEEE 802.11 b/g WLAN to mobile clients, while a wireless sniffer captures and analyzes network traffic. With the use of custom software we had developed, we can use our testbed to analyze and characterize the streaming traffic from multiple layers, such as the application layer, network layer and the wireless MAC layer.
Figure 1. Wireless Streaming Multimedia Testbed
The streaming server is capable of serving popular commercial streaming formats, such as RealNetworks, Windows Media, and Quicktime. In addition, the server can deliver live streaming encoding from multiple media capture devices, as well as pre-record contents from disk. The server uses ethereal packet capture software, as needed.
The streaming server connects to a wireless Access Point via a 100M LAN. The Access Point provides IEEE 802.11 b/g WLAN connections for mobile client.
Notebook computers are used as mobile clients to connect and playback media content served by media server. Our customized media players, Media Tracker and Real Tracker are used to playback media content and record the application layer statistical information.
The mobile clients have monitoring software installed to record the current connection status of the Access Point. Network level packet capture software, such as Ethereal, are used as needed.
The wireless sniffer has a IEEE 802.11 b/g PCI WLAN adapter installed. By setting the adapter to monitoring mode, Ethereal packet capture software is able to capture the MAC layer packets of IEEE 801.11 b/g WLAN protocol, including the management frame and beacons.
Jon Gretarsson, Feng Li, Mingzhe Li, Ashish Samant, Huahui Wu, Mark Claypool and Robert Kinicki. Performance Analysis of the Intertwined Effects between Network Layers for 802.11g Transmissions, In Proceedings of the 1st ACM Workshop on Wireless Multimedia Networking and Performance Modeling (WMuNeP), Montreal, Canada, October 2005. Online at: http://www.cs.wpi.edu/~claypool/papers/co-ap/
Mark Claypool. On the 802.11 Turbulence of Nintendo DS and Sony PSP Hand-held Network Games, In Proceedings of the 4th ACM Network and System Support for Games (NetGames), Hawthorne, NY, USA, October 2005. Winner! Best paper award. Online at: http://www.cs.wpi.edu/~claypool/papers/hand-held/
Mingzhe Li, Feng Li, Mark Claypool, and Robert Kinicki. Weather Forecasting - Predicting Performance for Streaming Video over Wireless LANs, In Proceedings of the 15th ACM International Workshop on Network and Operating Systems Support for Digital Audio and Video (NOSSDAV), Stevenson, Washington, USA, June 2005. Online at: http://www.cs.wpi.edu/~claypool/papers/weather/
Feng Li, Jae Chung, Mingzhe Li, Huahui Wu, Mark Claypool, and Robert Kinicki. Application, Network and Link Layer Measurements of Streaming Video over a Wireless Campus Network, In Proceedings of the 6th Passive and Active Measurement Workshop (PAM), Boston, Massachusetts, USA, April 2005. Online at: http://www.cs.wpi.edu/~claypool/papers/wlan/
Mingzhe Li, Choong-Soo Lee, Emmanuel Agu, Mark Claypool, and Robert Kinicki. Performance Enhancement of TFRC in Wireless Ad Hoc Networks, In Proceedings of the 10th International Conference on Distributed Multimedia Systems (DMS), San Francisco, California, September 2004. Online at: http://www.cs.wpi.edu/~claypool/papers/re-tfrc/
Choong-Soo Lee, Mingzhe Li, Emmanuel Agu, Mark Claypool and Robert Kinicki. Low Delay Marking for TCP in Wireless Ad Hoc Networks , In Proceedings of IEEE Workshop on Multihop Wireless Networks (MWN), Phoenix, Arizona, USA, April 2004. Online at: http://www.cs.wpi.edu/~claypool/papers/ldm/
Mingzhe Li, Mark Claypool, and Bob Kinicki, Wireless sniffing by example - how to build and use an ieee 802.11 wireless network sniffer, Tech. Rep. WPI-CS-TR-05-19, Department of Computer Science at Worcester Polytechnic Institute, Nov. 2005, Online at: ftp://ftp.cs.wpi.edu/pub/techreports/pdf/05-19.pdf.
Wireless streaming multimedia performance measurement
Capacity estimation for streaming multimedia over wireless
Forward Error Correction of streaming multimedia study over wireless
Buffering of streaming multimedia over wireless
Media scaling over wireless
The Real 10 Platform from RealNetworks.
Helix Community - A open community for digital media delivery for Real.
WindowsMedia.com The Windows Media Home.
Quicktime from Apple.
Darwin - A open source streaming server for QuickTime.
This material is based upon work supported by the National Science Foundation under Grant Number 0303592. Any opinions, findings and conclusions or recomendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF).