Research

Multi-user Extended Reality and the Metaverse (Ongoing)

Description: In this newly launched project, we are investigatinghow people can collaborate in an immersive environment, for example, the Metaverse. It overlaps with other ongoing efforts such as multi-user augmented reality (IEEE VR 2022) and multi-user volumetric video streaming (ACM HotNets 2021).

1. CoMIC: A Collaborative Mobile Immersive Computing Infrastructure for Conducting Multi-user XR Research
   Bo Han, Parth Pathak, Songqing Chen, and Lap-Fai (Craig) Yu
   To appear in IEEE Network Magazine.
   

2. Are We Ready for Metaverse? A Measurement Study of Social Virtual Reality Platforms
   Ruizhi Cheng, Nan Wu, Matteo Varvello, Songqing Chen, and Bo Han
   To appear in Proceedings of the 22nd ACM Internet Measurement Conference (IMC 2022).
   

3. Will Metaverse be NextG Internet? Vision, Hype, and Reality
   Ruizhi Cheng, Nan Wu, Songqing Chen, and Bo Han
   To appear in IEEE Network Magazine.
   

Mobile 3D Vision in Spatial Computing (Ongoing)

Description: In this project, we are examining how to perceive and understand the physical world in 3D to facilitate mobile spatial computing.

1. DeepMix: Mobility-aware, Lightweight, and Hybrid 3D Object Detection for Headsets
   Yongjie Guan, Xueyu Hou, Nan Wu, Bo Han, and Tao Han
   In Proceedings of the 20th ACM International Conference on Mobile Systems, Applications, and Services (MobiSys 2022), pages 28-41, June, 2022.
   

2. Preserving Privacy in Mobile Spatial Computing
   Nan Wu, Ruizhi Cheng, Songqing Chen, and Bo Han
   In Proceedings of the 32nd Workshop on Network and Operating System Support for Digital Audio and Video (NOSSDAV 2022), co-located with the 13th ACM Multimedia Systems Conference (MMSys 2022), pages 1-7, March, 2022.
   

3. Hybrid Mobile Vision for Emerging Applications
   Nan Wu, Felix Lin, Feng Qian, Bo Han
   In Proceedings of the 23nd ACM Workshop on Mobile Computing Systems and Applications (HotMobile 2022), pages 61-67, March, 2022.
   

4. Slimmer: Accelerating 3D Semantic Segmentation for Mobile Augmented Reality
   Huanle Zhang, Bo Han, Cheuk Yiu Ip, and Prasant Mohapatra
   In Proceedings of the 17th International Conference on Mobile Ad Hoc and Sensor Systems (MASS 2020), pages 603-612, December 2020.
   

Mobile Augmented/Mixed Reality (Ongoing)

Description: We are exploring the networking challenges of supporting augmented/mixed reality (AR/MR) on commodity mobile devices. We have utilized GPU acceleration at the network edge to reduce end-to-end latency of mobile AR (ACM Multimedia 2018) and on-device collaborative caching to address the scalability of edge-assisted mobile AR (ACM HotMobile 2018). We are now investigating headset-based mobile MR on devices such as Microsoft HoloLens 2 and Magic Leap One.

1. SEAR: Scaling Experiences in Multi-user Augmented Reality
   Wenxiao Zhang, Bo Han, and Pan Hui
   In Proceedings of the 29th IEEE Conference on Virtual Reality and 3D User Interfaces (VR 2022), pages -, March, 2022.
   (Also appears in IEEE Transactions on Visualization and Computer Graphics, Journal Track of IEEE VR 2022.)
   

2. Jaguar: Low Latency Mobile Augmented Reality with Flexible Tracking
   Wenxiao Zhang, Bo Han, and Pan Hui
   In Proceedings of the ACM Multimedia Conference (SIGMM 2018), pages 355-363, October, 2018.
   

3. CARS: Collaborative Augmented Reality for Socialization
   Wenxiao Zhang, Bo Han, Pan Hui, Vijay Gopalakrishnan, Eric Zavesky, and Feng Qian
   In Proceedings of the 19th ACM Workshop on Mobile Computing Systems and Applications (HotMobile 2018), pages 25-30, February, 2018.
   

Volumetric Video Streaming (Ongoing)

Description: As a natural extension of our past efforts on 360-degree video streaming, we are investigating the delivery of volumetric content that enables six degrees of freedom (6DoF). We have made a seminal contribution to volumetric video streaming by proposing a few visibility-aware optimization such as occlusion visibility and distance visibility (ACM MobiCom 2020). We have leveraged techniques such as remote content rendering and 3D content super resolution (ACM HotMobile 2021) to improve the performance of volumetric video streaming. We are now investigating more challenging research problems such as multi-user volumetric video streaming and live volumetric video streaming.

1. Vues: Practical Volumetric Video Streaming through Multiview Transcoding
   Yu Liu, Bo Han, Feng Qian, Arvind Narayanan, and Zhi-Li Zhang
   In Proceedings of the 28th ACM Conference on Mobile Computing and Networking (MobiCom 2022), pages -, September, 2022.
   

2. Innovating Multi-user Volumetric Video Streaming through Cross-layer Design
   Ding Zhang, Bo Han, Parth Pathak, and Haoliang Wang
   In Proceedings of the 20th ACM Workshop on Hot Topics in Networks (HotNets 2021), pages 16-22, November, 2021.
   

3. ViVo: Visibility-Aware Mobile Volumetric Video Streaming
   Bo Han, Yu Liu, and Feng Qian
   In Proceedings of the 26th ACM Conference on Mobile Computing and Networking (MobiCom 2020), pages 11:1-11:13, September 2020.
   

360-degree Video Streaming (Past)

Description: 360-degree videos are recorded using omni-directional cameras and thus allow users to freely control their viewing directions during playback. Streaming 360-degree videos to mobile devices is challenging, due to its high bandwidth demand. For example, to achieve the same perceived quality, the size of 360-degree videos is about 5X larger than that of conventional videos. We were among the first to propose viewport-adaptive 360-degree video streaming that improves mobile data usage and boosts quality of user experience (ACM MobiCom 2018). Other efforts in this project include investigation of live 360-degree video streaming (ACM MMSys 2019), analysis of viewport prediction under different interaction methods (ACM CoNEXT 2019), and delivery of ultra-high-definition 360-degree videos (WWW 2021). This project started my journey with mobile immersive computing.

1. DeepVista: 16K Panoramic Cinema on Your Mobile Device
   Wenxiao Zhang, Feng Qian, Bo Han, and Pan Hui
   In Proceedings of the 30th Web Conference (WWW 2021), pages 2232-2244, April, 2021.
   

2. Analyzing Viewport Prediction Under Different VR Interactions
   Tan Xu, Bo Han, and Feng Qian
   In Proceedings of the 15th International Conference on emerging Networking EXperiments and Technologies (CoNEXT 2019), pages 165-171, December, 2019.
   

3. LIME: Understanding Commercial 360-degree Live Video Streaming Services
   Xing Liu, Bo Han, Feng Qian, and Matteo Varvello
   In Proceedings of the 10th ACM Multimedia Systems Conference (MMSys 2019), pages 154-164, June, 2019.
   

4. Flare: Practical Viewport-Adaptive 360-Degree Video Streaming for Mobile Devices
   Feng Qian, Bo Han, Qingyang Xiao, and Vijay Gopalakrishnan
   In Proceedings of the 24th ACM Conference on Mobile Computing and Networking (MobiCom 2018), pages 99-114, October-November, 2018.
   

Network Management & Automation (Past)

Description: When I worked at AT&T Labs – Research, I initiated several projects on facilitating network management and automation, by leveraging key techniques such as network functions virtualization (NFV) and software-defined networking (SDN). More specifically, we studied how to improve the resiliency of virtual network functions (VNFs), the efficacy of service function chaining (SFC), and the generalizability of traffic management in production networks (IEEE COMMAG 2015 & 2017, ACM SOSR 2015 & 2017, and ACM CoNEXT 2019).

1. Egret: Simplifying Traffic Management for Physical and Virtual Network Functions
   Yikai Lin, Ajay Mahimkar, Bo Han, Zihui Ge, and Z. Morley Mao
   In Proceedings of the 15th International Conference on emerging Networking EXperiments and Technologies (CoNEXT 2019), pages 334-340, December, 2019.
   

2. On the Resiliency of Virtual Network Functions
   Bo Han, Vijay Gopalakrishnan, Gnanavelkandan Kathirvel, and Aman Shaikh
   IEEE Communications Magazine, vol. 55, no. 7, pp. 152-157, July 2017.
   

3. ParaBox: Exploiting Parallelism for Virtual Network Functions in Service Chaining
   Yang Zhang, Bilal Anwer, Vijay Gopalakrishnan, Bo Han, Joshua Reich, Aman Shaikh, and Zhi-Li Zhang
   In Proceedings of the 3rd ACM Symposium on SDN Research (SOSR 2017), pages 143-149, April, 2017.
   

4. EdgePlex: Decomposing the Provider Edge for Flexibility and Reliability
   Angela Chiu, Vijay Gopalakrishnan, Bo Han, Murad Kablan, Oliver Spatscheck, Chengwei Wang, and Yang Xu
   In Proceedings of the Symposium on SDN Research 2015 (SOSR 2015), article No. 15, June 2015.
   

5. Network Function Virtualization: Challenges and Opportunities for Innovations
   Bo Han, Vijay Gopalakrishnan, Lusheng Ji, and Seungjoon Lee
   IEEE Communications Magazine, vol. 53, no. 2, pp. 90-97, February 2015.
   

Mobile Opportunistic Networks (Past)

Description: In this project, we investigated how to efficiently combine data transmission over WiFi, Bluetooth, and cellular links in mobile opportunistic networks. The first part of this effort focused on offloading cellular network traffic to local communications via WiFi or Bluetooth on mobile devices. We studied various research problems such as influential mobile user selection and energy-efficient device discovery (IEEE TMC 2012, ACM MobiHoc 2012, IEEE ICNP 2012, IEEE/ACM TNET 2014, and IEEE TMC 2015). This part contributes as a major component of my Ph.D. dissertation. Motivated by the key observations in cellular traffic offloading, we explored how to leverage multi-path TCP (MPTCP) to improve the fairness among users and boost the performance of mobile applications such as web browsing and video streaming (IEEE ICNP 2014 and ACM CoNEXT 2015 & 2016).

1. MP-DASH: Adaptive Video Streaming Over Preference-Aware Multipath
   Bo Han, Feng Qian, Lusheng Ji, and Vijay Gopalakrishnan
   In Proceedings of the 12th International Conference on emerging Networking EXperiments and Technologies (CoNEXT 2016), pages 129-143, December 2016.
   

2. An Anatomy of Mobile Web Performance over Multipath TCP
   Bo Han, Feng Qian, Shuai Hao, and Lusheng Ji
   In Proceedings of the 11th International Conference on emerging Networking EXperiments and Technologies (CoNEXT 2015), article No. 5, December 2015.
   

3. On the Energy Efficiency of Device Discovery in Mobile Opportunistic Networks: A Systematic Approach
   Bo Han, Jian Li, and Aravind Srinivasan
   IEEE/ACM Transactions on Mobile Computing, vol. 14, no. 4, pp. 786-799, April 2015.
   

4. Multi-Path TCP: Boosting Fairness in Cellular Networks
   Ashwin Sridharan, Rakesh K. Sinha, Rittwik Jana, Bo Han, K. K. Ramakrishnan, N. K. Shankaranarayanan, and Ioannis Broustis
   In Proceedings of the 22nd IEEE International Conference on Network Protocols (ICNP 2014), pages 275-280, October 2014.
   

5. Your Friends Have More Friends Than You Do: Identifying Influential Mobile Users Through Random-Walk Sampling
   Bo Han, Jian Li, and Aravind Srinivasan
   IEEE/ACM Transactions on Networking, vol. 22, no. 5, pp. 1389-1400, October 2014.
   

6. eDiscovery: Energy Efficient Device Discovery for Mobile Opportunistic Communications
   Bo Han and Aravind Srinivasan
   In Proceedings of the 20th IEEE International Conference on Network Protocols (ICNP 2012), pages 1-10, October-November 2012.
   

7. Your Friends Have More Friends Than You Do: Identifying Influential Mobile Users Through Random Walks
   Bo Han and Aravind Srinivasan
   In Proceedings of the 13th ACM International Symposium on Mobile Ad Hoc Networking and Computing (MobiHoc 2012), pages 5-14, June 2012.
   

8. Mobile Data Offloading through Opportunistic Communications and Social Participation
   Bo Han, Pan Hui, V. S. Anil Kumar, Madhav V. Marathe, Jianhua Shao, and Aravind Srinivasan
   IEEE Transactions on Mobile Computing, vol. 11, no. 5, pp. 821-834, May 2012.
   

802.11 WiFi Networks (Past)

Description: In this project, we explored different aspects of IEEE 802.11 WiFi networks. (1). We started by first conducting extensive experiments to study the characteristics of sub-frame bit errors and their location distribution when data packets are delivered over WiFi networks, through which we identified three repeatable bit error patterns that are not induced by channel conditions. We verified that such error patterns are present in WLAN transmissions in different physical environments and across different wireless LAN hardware platforms (IEEE INFOCOM 2009 and IEE/ACM TNET). (2). In the second part of this project, we extended IEEE 802.11e EDCA with channel access throttling for more flexible and efficient QoS support and evaluated the performance of CAT with both simulations and experiments conducted using off-the-shelf WLAN hardware and open-source device drivers (IEEE SECON 2009). (3). Finally, motivated by our study of bit error patterns, we designed Maranello, a novel partial packet recovery mechanism for 802.11. We implemented Maranello using OpenFWWF (open-source firmware for Broadcom wireless cards), We deployed Maranello in a small testbed and evaluated its performance using real-world experiments under various channel conditions (USENIX NSDI 2010). This project was conducted mainly through research collaboration with AT&T Labs – Research when I was a Ph.D. student at the University of Maryland.

1. Are All Bits Equal? - Experimental Study of IEEE 802.11 Communication Bit Errors
   Bo Han, Lusheng Ji, Seungjoon Lee, Bobby Bhattacharjee, and Robert R. Miller
   IEEE/ACM Transactions on Networking, vol. 20, no. 6, pp. 1695-1706, December 2012.
   

2. Maranello: Practical Partial Packet Recovery for 802.11
   Bo Han, Aaron Schulman, Francesco Gringoli, Neil Spring, Bobby Bhattacharjee, Lorenzo Nava, Lusheng Ji, Seungjoon Lee, and Robert R. Miller
   In Proceedings of the 7th USENIX Symposium on Networked Systems Design and Implementation (NSDI 2010), pages 1-14, April 2010.
   

3. Channel Access Throttling for Improving WLAN QoS
   Bo Han, Lusheng Ji, Seungjoon Lee, Robert R. Miller, and Bobby Bhattacharjee
   In Proceedings of the 6th IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON 2009), pages 1-9, June 2009.
   

4. All Bits Are Not Equal - A Study of IEEE 802.11 Communication Bit Errors
   Bo Han, Lusheng Ji, Seungjoon Lee, Bobby Bhattacharjee, and Robert R. Miller
   In Proceedings of the 28th IEEE Conference on Computer Communications (INFOCOM 2009), pages 1602-1610, April 2009.