Portrait of Ranveer Chandra

Ranveer Chandra

Principal Researcher

About

More about my research is available in the following MSR Luminaries interview, and article, and the recent Economist article. We recently published a paper describing our White Space Deployments in Africa.

Key projects:

IoT Applications: Leading research on the end-to-end design of IoT Applications, with an initial focus on Agriculture. Read the Economist article here.
Battery Research at Microsoft: Leading this effort since 2011. Shipped several innovations in products, such as Visual Studio and Windows. Two key research themes are: offload (MAUI, WearDrive, Somniloquy) and new battery architectures, e.g. Software Defined Batteries.
TV White Spaces: Started this project in 2005. Awarded MIT TR-35 Award for WhiteFi. Now working on worldwide deployments and policy.
Low Latency Wireless: Designed the XBOX One Wireless Controller Protocol. This is shipping on 10 million+ XBOXes,
VirtualWiFi: Ph.D. Thesis. This has led to the design of Wi-Fi Direct. Software has over half million downloads.

Bio:

Ranveer Chandra is a Principal Researcher at Microsoft Research where he is leading an Incubation on IoT Applications. His research has shipped as part of multiple Microsoft products, including VirtualWiFi in Windows 7 onwards, low power Wi-Fi in Windows 8, Energy Profiler in Visual Studio, and the Wireless Controller Protocol in XBOX One. He is active in the networking and systems research community, and has served as the Program Committee Chair of IEEE DySPAN 2012, and ACM MobiCom 2013.

Ranveer is leading the battery research project, and co-leading the white space networking project at Microsoft Research. He was invited to the FCC to present his work on TV white spaces, and spectrum regulators from India, China, Brazil, Singapore and US (including the FCC chairman) have visited the Microsoft campus to see his deployment of the world’s first urban white space network. As part of his doctoral dissertation, Ranveer developed VirtualWiFi. The software has been downloaded more than 500,000 times and is among the top 5 downloaded software released by Microsoft Research. It is shipping as a feature in Windows since 2009.

Ranveer has published more than 60 papers, and filed over 100 patents, more than 65 of which have been granted by the USPTO. His research has been cited by the popular press, such as CNET, MIT Technology Review, Scientific American, New York Times, WSJ, among others. He has won several awards, including best paper awards at ACM CoNext 2008, ACM SIGCOMM 2009, IEEE RTSS 2014, and USENIX ATC 2015, the Microsoft Research Graduate Fellowship, the Microsoft Gold Star Award, the MIT Technology Review’s Top Innovators Under 35, TR35 (2010) and Fellow in Communications, World Technology Network (2012). Ranveer has an undergraduate degree from IIT Kharagpur, India and a PhD from Cornell University.

For a more detailed CV, click here.

Projects

FarmBeats: IoT for agriculture

Established: April 14, 2016

Several studies have demonstrated the need for the world’s food production to double by 2050. However, there is limited amount of additional arable land, and water levels have also been receding. Although technology could help the farmer, its adoption is…

PinDrop

Established: May 28, 2015

The PinDrop project focuses on building the substrate for supporting high-quality real-time streaming over wired and wireless networks. Context Real-time streaming across the wide-area network (WAN) is key to several existing and anticipated services, including voice and video conferencing (e.g.,…

Dynamic Spectrum and TV White Spaces

Established: November 30, 2012

The Spectrum Opportunity Microsoft is working with key partners around the world to ensure consumers have access to an increasing range of connected devices. To meet growing consumer demand and address other policy challenges, we must consider multiple approaches which…

Battery Research at Microsoft

Established: March 19, 2015

Mobile devices such as smartphones, along with other battery operated devices, are energy constrained. While hardware capabilities have increased tremendously over the last ten years, battery energy density has only doubled. In this project we are exploring several techniques to…

Mobile Assistance Using Infrastructure (MAUI)

Established: September 9, 2009

The Mobile Assistance Using Infrastructure (MAUI) project enables a new class of cpu- and data-intensive applications that seamlessly augment the cognitive abilities of users by exploiting speech recognition, NLP, vision, machine learning, and augmented reality. it overcomes the energy limitations…

Networking Over White Spaces (KNOWS)

Established: December 19, 2008

The next generation of wireless networks will include software defined radios, cognitive radios, and multi-radio systems which will co-exist harmoniously while operating over a very wide range of frequencies. Under the umbrella of the KNOWS project we are revisiting "classical"…

NetHealth

Established: January 6, 2007

Overview Networks are being deployed extensively in large corporations, small offices, and homes. However, a significant number of "pain points" remain for end-users and network administrators. To resolve complaints quickly and efficiently, network administrators need tools that can assist them…

Publications

2016

2015

Software Defined Batteries
Anirudh Badam, Ranveer Chandra, Jon Dutra, Anthony Ferrese, Steve Hodges, Pan Hu, Julia Meinershagen, Thomas Moscibroda, Bodhi Priyantha, Evangelia Skiani, in Symposium on Operating Systems Principles (SOSP'15), ACM – Association for Computing Machinery, October 5, 2015, View abstract, Download PDF

2014

2013

2012

2011

2010

2009

2008

2007

2006

Discovering Dependencies for Network Management
Victor Bahl, Paul Barham, Richard Black, Ranveer Chandra, Moises Goldszmidt, Rebecca Isaacs, Srikanth Kandula, Lun Li, John MacCormick, Dave Maltz, Richard Mortier, Mike Wawrzoniak, Ming Zhang, in Workshop on Hot Topics in Networks (HotNets-V), Association for Computing Machinery, Inc., November 1, 2006, View abstract, Download PDF

2005

2004

2003

2002

2001

Projects

Other

Awards

  • Microsoft Research Luminaries Series 2014 (Article & Video)
  • MIT Technology Review TR-35 (35 top innovators under 35) in 2010 (Profile)
  • Fellow in Communications, World Technology Network 2012
  • Microsoft Gold Star Award 2010
  • ACM SIGCOMM Best Paper Award, 2009
  • ACM CoNEXT Best Paper Award, 2008
  • IEEE RTSS, Best Paper Award, 2014
  • USENIX Annual Technical Conference, Best Paper Award, 2015
  • GigaOM Top 15 Mobile Influencers
  • Microsoft Graduate Research Fellowship, 2002 to 2005

Professional Service

Students

I have served on the Ph.D. committees of:

  • Omid Fatemieh (UIUC, 2011, now at Microsoft)
  • Eric Rozner (UT Austin, 2011, now at IBM Research)
  • Shravan Rayanchu (U Wisconsin, 2012, now at Google)
  • Souvik Sen (Duke, 2012, now at HP Labs).
  • Parya Moinzadeh (UIUC, 2013, now at Google)
  • Farhana Ashraf (UIUC, 2013)
  • George Nychis (CMU, 2013, now at Adaptrum)
  • Mariya Zheleva (UCSB, 2014, now at SUNY)
  • Apurv Bhartia (UT Austin, 2014, now at Meraki)

I have also worked with some very good interns:

  • Yuvraj Agarwal (UCSD)
    2006: Reducing power consumption of VoIP over Wi-Fi for smartphones
    2007: Worked on reducing energy consumption of desktop PCs and laptops
    Currently Assistant Professor in CMU, Previously Director of SYNERGY Labs @ UCSD
  • Apurv Bhartia (UT Austin)
    2011: Designed efficient wireless display mechanisms
  • Aakanksha Chowdhery (Stanford)
    2012: Investigated Dynamic Spectrum Access techniques in various spectrum bands
    Now at Microsoft Research
  • Saumitra Das (Purdue)
    2006: New routing metrics for mesh networks
    Currently Sr. Systems Engineer, R&D at Qualcomm
  • Chris Dekmezian (UC Berkeley)
    2015: New dynamic battery deigns
  • Omid Fatemieh (UIUC)
    2008 to 2010: Security in White Space networks
    Now at Microsoft
  • Tony Ferresse (UC Berkeley)
    2014: Investigated chemistries to be used in multi-battery mobile systems
  • Tulika Garg (IIT Roorkee)
    2006: Implemented MCL in QualNet
  • Pan Hu (UMass)
    2014: Designed hardware for multi-battery mobile systems
  • Junchen Jiang (CMU)
    2013: Security in mobile systems
  • Xinxin Jin (UCSD)
    2015: Cloud for weakly connected IoT systems
  • Srikanth Kandula (MIT)
    2006: Developed algorithms for localizing faults in enterprise networks
    2007: Developed eXpose for determining communication rules in a packet trace
    Now at Microsoft Research
  • Zerina Kapetanovic (University of Washington)
    2015: Sensors, solar panels, and white spaces for IoT deployments
  • Manikanta Kotaru (Stanford)
    2015: Diagnosing Skype call quality over wireless networks
  • Lopa Kundu (NCSU)
    2015: Efficient antenna designs for small form factor mobile devices
  • Amy Kumar (U. Iowa)
    2015: Single radio design for XBOX
  • Jing Li (UCSD)
    2013: Studied the energy overhead of mobile storage systems
  • Lun Li (Caltech)
    2006: Algorithms for a black box technique to detect faults using packet traces
  • Qingxi Li (UIUC)
    2011: Techniques for low-latency wireless display
  • Radhika Mittal (IIT Kharagpur, now at UC Berkeley)
    2011: An energy estimator for mobile apps
    Now Ph.D. student at UC Berkeley
  • Parya Moinzadeh (UIUC)
    2012: Developed data driven techniques for diagnosing energy bugs on mobile devices
    Now at Google
  • Rohan Murty (Harvard)
    2006-2007: Design and implementation of a dense access point system
    2008: Worked on protocols for networking in UHF bands
    2009: Worked on a geo-location service for white spaces
    Now Harvard Fellow, EVP at Infosys
  • Andres Neyem (University of Chile)
    2009: Designed a system for proximity sensing
    Now Professor at Pontificia Universidad Católica de Chile
  • George Nychis (CMU)
    2009:
    Worked on MIC interference issues in white spaces & campus deployment
    2010: Studies loss characteristics in wireless networks
    Now at Adaptrum
  • Ki-Woong Park (KAIST)
    2009: Designed and implemented a new system for social networking on phones
  • Chunyi Peng (UCLA)
    2013: Modulation techniques to be used in the XBOX One
    Now Assistant Professor in Ohio State
  • Ramya Raghavendra (UCSB)
    2007: Worked on applications of variable channel widths in 802.11
    Now at IBM Research, TJ Watson
  • Hariharan Rahul (MIT)
    2009: Designed algorithms for coexistence in white space networks
  • Shravan Rayanchu (Wisconsin)
    2010: Working on real-world channel width adaptation algorithms
    Now at Google
  • Eric Rozner (UT Austin)
    2010: Studied loss characteristics in wireless networks
    Now at IBM Research, Previously at AT&T Research
  • Jinghao Shi (SUNY Buffalo)
    2015: Wireless protocol verification
  • Evangelia Skiani (Columbia)
    2014: Algorithms to use multi-battery systems
  • Deepak Vasisht (MIT)
    2015: Design of an IoT Edge, and the Machine Learning and Vision algorithms.
  • Xiaohui (Eeyore) Wang (CMU)
    2009: Explored changes in the network stack for the next generation of networking technolgies
  • Jongho Won (Purdue)
    2015: Path planning and battery life optimizations for drones
  • Hang Yu (Rice)
    2 internships in 2012: Investigated techniques to use in the protocol of the XBOX One Wireless Controllers
  • Yuan Yuan (University of Maryland)
    Summer 2006, Fall 2006 & Spring 2007: Designed a new MAC for cognitive radios, and implemented it in QualNet
    Now at Google
  • Sangki Yun (UT Austin)
    2013: Studied bandwidth overlapping systems in 802.11ac
  • Mariya Zheleva (UCSB)
    2013: Worked on the spectrum observatory — to mine spectrum measurements for patters of spectrum use
  • Xia Zhou (UCSB)
    2011: Working on low power Wi-Fi mechanisms
    Now Assistant Professor in Dartmouth College

 

Press

Selected Press

On IoT and Agriculture:

On white spaces:

On Energy Management & Batteries:

On Channel Widths:

On VirtualWiFi:

Personal:

Talks

Panelist:

Selected Keynotes/Colloquia/Invited Talks:

Tech Transfers

I work closely with product teams within Microsoft. Some of the publically disclosed engagements are listed below.

XBOX One Wireless Controller Protocol (2013 to now)
The wireless protocol between the XBOX One controller and console

Designed the high-throughput, low-latency wireless protocol that shipped in the XBOX One. Research and industry has always focused on getting higher throughput. However, little prior work, if any, looks at achieving high throughput while achieving low (guaranteed) latency. For the XBOX One we designed a protocol that achieves both. I enjoyed being deeply involved with the design, development, and testing of the controllers.

Visual Studio 2013 Energy Profiler (2013) – Diagnostics & Performance Toolbox for Windows 8.1
Enables app developers to estimate the energy consumption of their apps

Described here, and also showcased in Steve Ballmer’s Build Keynote: (around 45th minute). Our research paper Empowering Developers to Estimate App Energy Consumption, published in ACM MobiCom 2012 describes the details of the system.

Low Energy Wi-Fi (2012) – Windows 8, Windows 10
Increases battery lifetime in Windows 8 Tablets and Surface computers.

Compared to laptops the new class of mobile devices, such as tablets and Surface computers, need to stay connected even when the screen is turned off. Keeping the Wi-Fi always on consumes significant energy. We designed a set of techniques that allows the Wi-Fi device to not lose its connection even when the screen is turned off and the processor (and SoC) is in a low power state. We accomplished this by reducing the Wi-Fi power consumption to a few mW in standby state. Our techniques shipped in Windows 8.

Antenna Placement on Windows Tablet (2012) – Windows 8.1
Enabled best-in-class Wi-Fi network connectivity & performance for tablets

We helped design the antenna placement on tablet devices. Since users hold tablets differently than laptops, existing antenna placement techniques (on the laptop’s screen) are not the most optimal for tablets. The placement of a user’s hand around the antenna might reduce the signal, and so can the orientation in which the tablet is held. We studied these phenomena in detail – in the wild and in antenna chambers – and made recommendations to the Windows 8 team, which were incorporated in the final design of Windows 8 tablets.

Visual Studio Energy Modeler & Profiler (2012) – Windows Phone 8 Dev Tools
Enables mobile app developers to estimate the energy consumption of their apps

Poorly written apps are one of the primary reasons for high energy drain on mobile devices. One reason for energy-inefficient apps is that app developers do not have sufficient tools to determine the energy impact of their apps. As part of a Wattson research project we designed a Visual Studio plug-in that provides visibility to the application developer of their application’s energy consumption. Our paper Empowering Developers to Estimate App Energy Consumption, published in ACM MobiCom 2012 describes the details of the system. This work formed the basis for the Energy Profiler that is part of the Visual Studio SDK for Windows Phone 8.

Singapore White Space Database (2012)
Used by Singapore’s regulatory authority in the Singapore White Space Trail
http://whitespaces.msresearch.us/Singapore/

White spaces profer to be a possible solution towards improving spectrum effiency. As part of our research since 2005, we developed a geo-location database service which returns a list of TV channels at any given location, and filed to be a white space database provider with the FCC. We are also working with governments outside the US with white space trials. We recently released a version of our database as part of the ongoing white spaces trial in Singapore.

Virtual Wi-Fi (2009) – Windows 7, Windows 8, Windows 10
Enables Windows to connect to multiple WLANs simultatenously. Is the foundation of SoftAP & Wi-Fi Direct features in Windows 7 & Windows 8

We designed a technique to virtualize wireless LAN (WLAN) cards. With it users can concurrently connect to multiple Wi-Fi networks using a single WLAN card, thus enabling several novel scenarios. The original paper. The original paper ( MultiNet: Connecting to Multiple IEEE 802.11 Networks Using a Single Wireless Card) was published in INFOCOM 2004. Our miniport driver was downloaded by over hundred thousand developers and was one of Microsoft Research’s most popular software downloads. Virtual Wi-Fi first shipped in Windows 7.

Research

My research focuses on different aspects of mobile computing, in particular wireless communications and energy efficiency. Currently I am working on three different projects:

    • White space networking in the TV bands and other portions of the spectrum (KNOWS Project page)
    • Low latency wireless for gaming and other real-time applications
    • Energy-efficient computing for smartphones and tablets (Battery Project Page)

Video Links: An overview of my research is available in this MSR Luminaries Video. Some other video links are here: on white spaces, on improving battery life, and on code offload.

In the past I have worked on wireless management, mesh networks, enterprise network management, and different wireless architectures. More details about some of the projects are below.

White Space Networking (Cognitive Radios, SDRs, …)http://research.microsoft.com/knows

We started the KNOWS project at Microsoft Research in early 2006, and since then I have led the technical aspects of the project through three versions. In the first phase, we looked at the MAC protocol for white spaces in a mesh setting. In the second phase, we proposed WhiteFi, a system for providing Wi-Fi like connectivity for white spaces. In the third phase, we have now built and deployed a white space network in Microsoft campus. More details on this project can be found here.

Energy-Efficient Computing

I am working on ways to reduce the energy consumption of PCs and mobile phones. Somniloquy (NSDI 2009) provides a way to let PCs go to sleep mode without losing network connectivity. Cell2Notify is a notification architecture for mobile phones that allows devices to turn on Wi-Fi only when needed, thereby increasing their battery lifetime. This is an active project, and expect to see more information soon.

Network Management (eXpose, DAIR, Sherlock, …)
http://research.microsoft.com/nethealth

With the increasing complexity of enterprise networks, there is a pressing need for efficient approaches to detect, localize, diagnose and repair faults in the network. I have worked on several aspects of network management as part of a bigger project, called NetHealth. Sherlock uses dependency analysis to localize faults that impact end-users, DAIR helps IT administrators locate regions of poor WLAN coverage and performance, and WiFiProfiler enables users to collaborately diagnose Wi-Fi problems.

“Whats Going On? Extracting Communication Rules in Edge Networks”, Srikanth Kandula, Ranveer Chandra, Dina Katabi. Proceedings of ACM SIGCOMM, Seattle, August 17-22, 2008

Mobile Systems

Smartphones are becoming extremely popular. While they provide a new and unique user experience, several key problems need to solve to fully realize their potential. First, RF spectrum is limited, and a proliferation of smartphones has led to significantly degraded performance. This is likely to become worse in the future. Second, battery technology is not evolving at the same pace as applications, and the energy-hungry applications on a smartphone quickly drain its battery. With these constraints in mind, I have been working on technologies and applications to make better use to the RF spectrum while consuming lesser energy.

  • “MAUI: Making Smartphones Last Longer with Code Offload”, Eduardo Cuervo, Aruna Balasubramanian, Dae-ki Cho, Alec Wolman, Stefan Saroiu, Ranveer Chandra, Paramvir Bahl, Proceedings of ACM MobiSys 2010, June 15-18, 2010.
  • “Virtual Compass: Relative Positioning to Sense Mobile Social Interactions”, Nilanjan Banerjee, Sharad Agarwal, Paramvir Bahl, Ranveer Chandra, Alec Wolman, Mark Corner, Proceedings of Pervasive, May 17-20, 2010.
  • “Wi-Fi Neighborcast: Enabling Communication Among Nearby Clients”, Ranveer Chandra, Jitendra Padhye, Lenin Ravindrananth. Proceedings of ACM HotMobile, Napa Valley, February 25-26, 2008.
  • “BeaconStuffing: Wi-Fi Without Associations”, Ranveer Chandra, Jitendra Padhye, Lenin Ravindrananth, Alec Wolman. Proceedings of IEEE HotMobile, Tucson, February 26-27, 2007.
  • “Wireless Wakeups Revisited: Energy Management for VoIP Over Wi-Fi Smartphones”, Yuvraj Agarwal, Ranveer Chandra, Alec Wolman, Paramvir Bahl, Kevin Chin, Rajesh Gupta. Proceedings of ACM/USENIX MobiSys, Puerto Rico, June 11-14, 2007

Mesh Networks
http://research.microsoft.com/mesh

I have worked on networking issues in layer 2 and layer 3 (both on unicast and multicast) in wireless mesh networks. The details of this project are available on our group’s Mesh Networking page.

Rethinking the Design of Wireless Systems

Wi-Fi is designed as a convenient replacement for the wire, and its design mostly attempts to mimic the behavior of the Ethernet. For example, a Wi-Fi card needs to associate to an Access Point (AP) before it can send data packets, which is similar to the action to plugging the Ethernet cable in the wall. Furthermore, Wi-Fi restricts a card to associate to at most one AP. In my opinion, the wireless medium has a number of powerful properties and wireless networks should be treated differently from traditional wired networks. I have built some systems that try to break away from these constraints in Wi-Fi networks as part of VirtualWiFi and WiFiAds projects.