Mobility and Networking Research

Established: July 12, 2012

The Mobility and Networking Research (MNR) Group focuses on basic and applied research in all areas related to networked systems and mobile computing. Researchers build proof-of-concept systems, engage with academia, publish scientific papers, publish software for the research community, and transfer cutting-edge technologies to Microsoft’s product groups.


Highlighted Project

Under the umbrella of the KNOWS project, we are revisiting classical wireless networking problems and designing new solutions that incorporate and build upon recent advances in software and hardware technologies for networking over the recently opened white spaces spectrum.

Feature Stories

  • Mobility and Networking Researchers Making a Big Impact in the Cloud 19 August 2014
  • Finding More Space in Spectrum 29 January 2014
  • Bahl Awarded SIGMOBILE’s Top Honor 1 October 2013
  • Big Advances in Data-Center Networking 12 August 2013
  • Bahl Achieves Alma Mater’s Distinction 17 April 2012
  • Multiplayer Gaming for Smartphones 28 June 2011
  • Tuning Smartphone Performance 31 October 2010
  • Using Wi-Fi to Boost 3G Capacity 16 September 2010
  • Trying to Cure PC Insomnia 19 April 2010

Research Pillars

  • Cloud Services
  • SDN and Datacenter Networking
  • Network Management
  • Energy Management
  • Personalization & Social
  • Security & Trust
  • Hardware Accessories

Tech. Transfers

Product group impact comes in many forms – consultation, design wins, code transfer, people transfer etc. Here are some examples:

  • Microsoft’s Wide Area Software Defined Network
  • XBOX One Wireless Controller Protocol
  • Service Graphs for Large-Scale Network Diagnostics to XBOX Live
  • Mileage data attribution to Windows Phone 8
  • Network Failure Recovery in Data Centers to Bing
  • Support for Security Features in Windows ARM to Windows
  • Virtual Wi-Fi in Windows 7 to Windows
  • Fully Configurable Windows Azure Software Load Balancer\
  • Partitioning and Recovery Service in Live Mesh
  • Centrifuge/PRS in Windows Live Messenger
  • DNS optimization in Bing


Sample Technology Licensing

Visit for licensing information.

  • Wireless (Wi-Fi) Hot Spot Network Access: Package includes five technologies: Global Authentication; Network Admission; Traffic Gateway; Client Module and Policy Manager.
  • Wi-Fi Location Determination: Technology to locate a wireless client by pattern matching the measured signal strength from multiple wireless access points against a database of previously collected signal strength.
  • Cellphone Power Management: Technology that leverages the cellular radio to wake-up the Wi-Fi radio on SmartPhones, Laptops, and NetBooks.
  • Virtual WiFi:Technology that abstracts a single Wireless LAN card to appear as multiple virtual Wireless LAN cards to the user/OS.
  • Mesh Connectivity: Ad-hoc routing and link quality measurement for mesh networks as a loadable software driver.
  • Undelivered or Delayed e-mail Notification System: An alerting technology for users when e-mails sent to them have been delayed or lost.
  • High Performance Internet Connectivity in Moving VehiclesA set of protocols, algorithms, and mechanisms that enable moving clients to transmit data packets on the wireless link that offers the fastest delivery, which minimizes application traffic delays..
  • Fast Wi-Fi Hand-off to Diversified Base Stations: Technology that opportunistically exploits base station diversity to minimize connection disruptions while supporting interactive applications for moving Wi-FI enabled clients.
  • Smart Antenna:Low cost directional antenna technology designed for increasing the range, throughput, and consistency of 802.11 networks















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













Project Hawaii SDK 1.0.8

June 2011

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Broom Tool Kit to Unbias Network Measurements

November 2009

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Microsoft Research TCP Analyzer (x64)

June 2009

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Microsoft Research TCP Analyzer (x86)

March 2009

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ELDA (E-mail Loss-Detection Add-in)

February 2008

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Microsoft Research Virtual WiFi

August 2005

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May 31, 2013


Bridgett Crews


Microsoft Research

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October 1, 2012


Sharad Agarwal

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March 1, 2011


David Molnar and Sharad Agarwal


New Directions in Wireless Systems Design 2013

Redmond, WA | May 2013

Join us for a fast paced half-day summit where some of the most active wireless networking and systems researchers in academia and industry give short (~10 minute) presentations answering the following question: what are the cannot miss cutting-edge problem(s) they are working on and how will their solution(s) transform/impact our industry?  The goal of this informal event is to create stronger ties between Microsoft’s technical community leaders and some of the top wireless and mobile systems…


Data-Driven Speech Enhancement

Established: January 8, 2017

Speech enhancement is one of the oldest problems in signal processing, dating back to the 1940s. The goal of this task is to take an audio signal from a microphone, clean it and forward clean audio to multiple clients such as speech recognizers, archival databases and speakers. The performance of this process is measured by the intelligible quality of the clean signal to listeners, measured by standard metrics such as PESQ, and to speech-recognizers, measured…

ProjecToR: Agile Reconfigurable Data Center Interconnect

ProjecToR is a novel, free-space optics based approach for building data center interconnects. It uses a digital micromirror device (DMD) and mirror assembly combination as a transmitter and a photodetector on top of the rack as a receiver. Our approach enables all pairs of racks to establish direct links, and we can reconfigure such links (i.e., connect different rack pairs) within 12 µs. To carry traffic from a source to a destination rack, transmitters and…

Wide-Area Optical Backbone Performance

Wide-area backbone networks (WAN) of Internet service providers and cloud providers are the workhorses of Internet traffic delivery. The providers spend millions of dollars toward building access points across the world and interconnecting them using optical links. Improving the availability and efficiency of the WAN is central to their ability to provide services in a reliable, cost-effective manner. Consequently, there has been significant research into measuring and characterizing various aspects of the WAN, such as…

Cloud-Powered Virtual Reality

Established: June 3, 2016

We are investigating how Cloud Computing can enable next-generation Virtual Reality experiences. In The News Check out what the press has to say about our work. ProxyIBR:  Neowin FlashBack: Yahoo, Network World, Neowin, Phone Arena, WinBeta, MS Power User, SlashGear, ... Kahawai: ZDNET, Neowin, ExtremeTech, Geek Irides: Neowin, VG24/7, ct magazine Outatime: Tech Crunch, The Verge, Engadget, Slashdot, PC Magazine, GameSpot, The Register, PCWorld, Gizmodo, SlashGear, Ars Technia, The Motley Fool

Quickr: Cost-effective data analytics at scale

Established: March 8, 2016

We are inundated with data. Resources to analyze the data are finite and expensive. Approximate answers allow us to explore much larger amounts of data than otherwise possible given available resources. Reducing the cost, if doable for a large fraction of the complex queries that run on this data, is of strategic importance because the savings can be re-invested into more sophisticated algorithms or be used as a key differentiator for analytics-as-a-service offerings. Unfortunately, state-of-art…


Established: February 19, 2016

We are developing new techniques to efficiently deliver content and services over large-scale cloud infrastructure.

RDMA for Cloud Computing

Established: May 1, 2013

In this project, we have introduced a series of technologies, including DCQCN congestion control and DSCP-based PFC, and addressed a set of challenges including PFC deadlock, RDMA transport livelock, PFC pause frame storm, slow-receiver symptom, to make RDMA scalable and safe, and to enable RDMA deployable in production at large scale. We currently are working on RDMA deadlock understanding and prevention, and RDMA support for future AI infrastructure. RDMA Congestion Control Modern datacenter applications…

Project Hawaii

Established: November 9, 2012

The Project Hawaii program was discontinued on October 8, 2013. With Project Hawaii, you can develop cloud-enhanced mobile applications that access a set of cloud services and Windows Azure for computation and data storage. Project Hawaii provides the tools and services; you provide the creativity and imagination. Get the latest version: Project Hawaii Software Development Kit (SDK) Click to open Project Hawaii Discussions Forum.  The forum will open in a new window.…

HomeOS: Enabling smarter homes for everyone

Established: September 30, 2010

It is no secret that homes are ever-increasing hotbeds of new technology such as set-top boxes, game consoles, wireless routers, home automation devices, tablets, smart phones, and security cameras. This innovation is breeding heterogeneity and complexity that frustrates even technically-savvy users’ attempts to improve day-to-day life by implementing functionality that uses these devices in combination. For instance, it is impossible for most users…

Measurement-based models of wireless networks

Established: August 19, 2010

Based on detailed measurements of wireless behavior in the wild, we build practical models that aid in understanding and predicting network performance. Our goal is to have a level of predictability that is similar to that in wired networks. Talks Measurement-based models enable predictable wireless behavior KAIST, June 2009 Effects of Interference of Wireless Mesh Networks: Pathologies and a Preliminary Solution HotNets, Nov 2007 Analyzing the MAC-level behavior of Wireless Networks in the Wild SIGCOMM,…

NetMedic: Detailed and Understandable Network Diagnosis

Established: August 19, 2010

NetMedic helps operators perform detailed diagnosis in computer networks. It diagnoses not only generic faults (e.g., performance-related) but also application specfic faults (e.g., error codes). It identifies culprits at a fine granularity such as a process or firewall configuration. Our work focuses on both the algorithmic aspects of detailed diagnosis as well as the important task of explaining diagnostic reasoning to the operator. Talks Detailed and understandable network diagnosis University of Wisconsin, Nov 2009; Georgia…

Lockr: Better Privacy for Social Networks

Established: August 17, 2010

Today’s online social networking (OSN) sites do little to protect the privacy of their users’ social networking information. Given the highly sensitive nature of the information these sites store, it is understandable that many users feel victimized and disempowered by OSN providers’ terms of service. Lockr is a system that improves the privacy of centralized and decentralized online content sharing systems. Lockr offers three significant privacy benefits to OSN users. First, it separates social networking content…

Bunker: A Privacy-Oriented Platform for Network Tracing

Established: August 17, 2010

Bunker is a network tracing system that offers strong privacy while simplifying the development of network tracing software. With Bunker, network operators can perform network tracing based on the following two-step usage model: Pre-load Bunker with the trace collection and anonymization software. Start data collection with Bunker. With Bunker, all sensitive data is stored in a buffer on disk that is "locked down" along with the tracing software. In this way, no raw data can…

BlueMonarch: A System for Evaluating Bluetooth Applications in the Wild

Established: August 17, 2010

BlueMonarch is a system for evaluating Bluetooth applications in the wild. BlueMonarch emulates a Bluetooth transfer to any device responding to Bluetooth Service Discovery requests; because many cell-phones, laptops, and PDAs in the wild respond to such probes, BlueMonarch enables quick prototyping of Bluetooth applications in the wild, to hundreds of unmodified Bluetooth devices. This functionality makes BlueMonarch useful for evaluating a large class of Bluetooth applications, those in which a local server under the…

Cloud Faster

Established: February 25, 2010

To make cloud computing work, we must make applications run substantially faster, both over the Internet and within data centers. Our measurements of real applications show that today's protocols fall short, leading to slow page-load times across the Internet and congestion collapses inside the data center. We have developed a new suite of architectures and protocols that boost performance and the robustness of communications to overcome these problems. About Cloud Faster We have developed a…

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 of handhelds by leaveraging nearby computing infrastructure. Brief Description The size, weight, and battery life of mobile devices severely limit the class of applications that run on them. This is not just…

Microsoft Research TCP Analyzer

Established: June 22, 2009

This tool analyzes network traces of Transmission Control Protocol (TCP) connections. Given a Microsoft Network Monitor trace, the analyzer provides various performance statistics and visualizations for the captured TCP connection. Included are plots of the time-sequence graph, round-trip time measurements, and more. The tool also contains an analysis engine that attempts to explain what the limiting performance factor of a particular connection was. The analyzer installs itself as a Microsoft Network Monitor…


Established: December 22, 2008

Connecting to Multiple IEEE 802.11 Networks with one WiFi Card (VirtualWiFi is an old project, and we started working on it in 2002. We are not actively working on this project since 2006, and will not be supporting this software at Microsoft Research. Thanks for your interest. However, the software and code will still be available for you to play around with. Also, check out the supported VirtualWiFi OIDs in Windows 7.)

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" wireless networking problems and designing new solutions that incorporate and build upon recent advances in software and hardware technologies for networking over the recently opened white spaces spectrum. Brief Description The WhiteFiService APIs and web…

VanLan: Investigating Connectivity from Moving Vehicles

Established: February 27, 2008

Our goal is to enable cheap and high-throughput wireless connectivity to moving vehicles in urban areas. Our goal is to enable cheap and high-throughput wireless connectivity to moving vehicles in urban areas. The available options for such connectivity today fall short in significant ways. Cellular networks are expensive and have low throughput. Same is likely to be true of WiMax networks if they were to become a reality. While some exisiting WiFi basestations can provide…

Wi-Fi Ads

Established: July 28, 2007

Delivering Location-Based Content to Clients Over Wi-Fi Networks Overview Many consumers carry portable electronic devices, smartphones, personal digital assistants, or laptops that can connect to Wi-Fi networks. Location-sensitive advertisements, ads targeted to a Wi-Fi user based in part on the physical location of that user, will be an important market in the near future. We have developed two schemes for distributing location-sensitive ads to Wi-Fi devices: BeaconStuffing and Neighborcast. BeaconStuffing fragments large messages, and embeds…


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 in detecting, isolating, diagnosing, and correcting faults. Furthermore, such tools should also detect network security breaches, possibly caused by innocent employees. The NetHealth project is about detecting, inferring, diagnosing, and recovering from user perceived performance…

Self Organizing Wireless Mesh Networks

Established: October 12, 2004

Community-based multi-hop wireless networks is disruptive to the current broadband Internet access paradigm, which relies on cable and DSL being deployed in individual homes. It is important because it allows free flow of information without any moderation or selective rate control. Compared to the large DSL and cable modem systems that are centrally managed, mesh networking is organic — everyone in the neighborhood contributes network resources and cooperates. Overview Researchers in Microsoft Research Redmond, Cambridge,…


Established: November 5, 2001

RADAR is the world's first Wi-Fi signal-strength based indoor positioning system. RADAR proves that RF fingerprinting and environmental profiling with commodity wireless LAN hardware can be used to determine user and machine location inside buildings, thereby enabling indoor location-aware applications (think - "Indoor-GPS") Wherever You Go, There Is Connectivity by Suzanne Ross Victor Bahl, a researcher with the Systems and Networking group, says his kid doesn't get too excited about his work. "He's seen too…

MSR Blog

Mobility and Networking Researchers Making a Big Impact in the Cloud

The annual conference of the Association for Computing Machinery’s Special Interest Group on Data Communication (SIGCOMM) is always a highlight for those who follow the latest developments in applications, technologies, architectures, and protocols for computer communication. SIGCOMM 2014, to be held in Chicago from August 17 to 22, is definitely the highlight of the year for Victor Bahl, (@SuperBahl) director of Microsoft Research’s Mobility and Networking Research Group (MNR). Two of Bahl’s MNR colleagues are…

August 2014

Microsoft Research Blog

Finding More Space in Spectrum

Radio and TV channels, mobile communications, GPS, and emergency communications are just a few examples of applications that occupy the airwaves. The radio spectrum is a finite resource, but demand for bandwidth is accelerating. As a result, the telecommunications industry is facing what the U.S. Federal Communications Commission (FCC) calls “the impending spectrum crunch.” In Microsoft Research’s Mobility and Networking Research Group, senior researcher Ranveer Chandra has been co-leading the Networking Over White Spaces (KNOWS) project,…

January 2014

Microsoft Research Blog

Big Advances in Data-Center Networking

These are exciting times for networking researchers. New developments in data-center networking—and the new efficiencies those advances offer—are making this one of the hottest fields in computing. Major figures in networking and communications research gather in Hong Kong from August 12 to 16 for SIGCOMM 2013, the flagship annual conference of the Association for Computing Machinery’s Special Interest Group on Data Communications. And a trio of papers from the Mobility and Networking Research Group at…

August 2013

Microsoft Research Blog

Other Members

Other Members

Postdoctoral Researchers

Aakankha ChowdheryPhD Stanford University(2013-15)

Monia GhobadiPhD University of Toronto(2014-16)

Meg Walraed-SullivanPhD UC San Diego(2012-15)

Hongqiang LiuPhD Yale University(2014-16)

Visiting Researchers

Aditya AkellaAssociate ProfessorUniversity of WisconsinJan. – July 2014

Lin ZhongAssociate ProfessorRice UniversityJan. – Dec. 2012

Rodrigo FonsecaAssistant ProfessorBrown UniversitySummer 2012

Parmesh RamanathanProfessorUniversity of WisconsinSummer 2010

Romit Roy ChoudhuryAssociate ProfessorDuke University (now in UIUC)Summer 2010

Balaji PrabhakarProfessorStanford UniversitySummer 2009

Yang (Richard) YangAssociate ProfessorYale UniversitySummer 2009

Jennifer RexfordProfessorPrinceton UniversitySummer 2009

Charlie HuProfessorPurdueSummer 2008

Zhouqing Morley MaoAssociate ProfessorUniversity of MichiganSummer 2008

Past Members

Atul AdyaPhD MIT(no longer in MS)

Ranveer ChandraPRINCIPAL RESEARCHERPhD Cornell University(2005-15)

Ronnie ChaikenPRINCIPAL ENG. MANAGER(now in Power BI Data Services) (2011-14)

John DunaganPhD MIT(no longer in MS)

Albert GreenbergDISTINGUISHED ENGINEERPhD UWashington(now in Azure Networking)(2007-10)

David MaltzPARTNER DEV. MANAGERPhD CMU(now in Azure Networking)(2005-10)


Venkat PadmanabhanPRINCIPAL RESEARCHERPhD UC Berkeley(now in MSR India)

Parveen PatelPRINCIPAL SOFT. ENG. MGR.MS Utah(now in Windows Azure)

Lili QiuPROFESSOR, Computer ScienceUniversity of Texas, Austin(2001-04)

Brian ZillSENIOR RESEARCH SDEMS Carnegie Mellon

Students: PhD Fellows

Microsoft Research awards a two-year fellowship to outstanding Ph.D. students. The full description of the award is available on our Graduate Fellowship Program page. Past recipients with Ph.Ds. in Mobility & Networking are:

  • Pan Hu, U. Massachusetts Amherst (2015-17)
  • Yibo Zhu, UC Santa Barbara (2015-17)
  • Fadel Adib, MIT (2014-16)
  • Ashish Patro, University of Wisconsin (2012-14)
  • Lenin Ravindranath Sivalingam, MIT (2010-2012)
  • Shravan Rayanchu, University of Wisconsin (2009-11)
  • Rohan Narayana Murty, Harvard (2008-10)
  • Aruna Balasubramanian, U. Massachusetts Amherst (2008-10)
  • Karthik Lakshminarayanan, UC Berkeley (2005-07)
  • Jinyang Li, MIT (2004-05)
  • Qiang Huang, Princeton (2004-05)
  • Magdelena Balazinska, MIT (2003-05)
  • Ratul Mahajan, University of Washington (2003-05)
  • Ranveer Chandra, Cornell  (2002-05)
  • David Andersen, MIT (2002-04)

Summer 2015

  • Omid Alipourfard, Brown University
  • Kevin Boos, Rice University
  • Bo Chen, Ohio State University
  • Tiffany Chen, MIT
  • Seyed Fayazbakhsh, CMU
  • Jonas Fietz, EPFL
  • Rohan Gandhi, Purdue University
  • Petko Georgiev, U. Cambridge, U.K
  • Shubham Jain, Rutgers
  • Junchen Jiang, CMU
  • Yao Lu, University of Washington
  • Jon Mace, Brown University
  • Matthaios Olma, EPFL
  • Saman Naderiparizi, University of Washington
  • Justin Paupore, University of Michigan
  • Lalith Suresh Puthalath, TU-Berlin
  • Rahul Saladi, University of Minnesota
  • Lynn Salameh, University College London, U.K.
  • Aleksander Vitorovic, EPFL
  • Yang Wu, University of Pennsylvania
  • Chao Xie, University of Texas Austin
  • Haoyu Zhang, Princeton University
  • Yongle Zhang, University of Toronto
  • Hongze Zhao, Duke University
  • Yibo Zhu, University of California Santa Barbara
  • Danyang Zhuo, University of Washington

Summer 2014

  • Abigail Atchison, Tahoma High School
  • Anil Shanbhag, Massachusetts Institute of Technology
  • Shivani Bahl, Lakeside School (now at Cornell University)
  • Matt Calder, University of Southern California
  • Chen Chen, ETH Zurich
  • Kaifei Chen, University of California Berkeley
  • Tony Ferrese, University of California Berkeley
  • Peter Gao, University of California Berkeley
  • Robert Grandl, University of Wisconsin Madison
  • Kiryong Ha, Carnegie Mellon University
  • Pan Hu, UMASS Amherst
  • Ayush Kanodia, IIT Bombay
  • Junaid Khalid, University of Washington Madison
  • Rayman Preet Singh, University of Waterloo
  • Daniel Ohene-Kwofie, University of Witwatersrand
  • Qifan Pu, University of California Berkeley
  • Delsey Sabu, Seattle Pacific University
  • Haichen Shen, University of Washington
  • Clay Shepard, Rice University
  • Evangelia Skiani, Columbia University
  • Raajay Viswanathan, University of Wisconsin Madison
  • Tan Zhang, University of Wisconsin Madison
  • Yibo Zhu, University of California Santa Barbara

Summer 2013

  • Chen Chen, Carnegie Mellon University
  • Yu-Han (“Tiffany”) Chen, Massachusetts Institute of Technology
  • Lara Deek, University of California Santa Barbara
  • Ilan Ari Fogel, University of California Los Angeles
  • Rohan Gandhi, Purdue University
  • Robert Grandl, University of Wisconsin Madison
  • Cho-Yao Hong, University of Illinois Urbana Champaign
  • Xin Jin, Princeton University
  • Kyungmin (“Jason”) Lee, University of Michigan Ann Arbor
  • Frank Li, Massachusetts Institute of Technology
  • Robert LiKamWa, Rice University
  • Ashish Patro, University of Wisconsin Madison
  • Chunyi Peng, University of California Los Angeles
  • Sergey Grizan, Russian Intern Program
  • Anil Atmanand Shanbhag, Indian Institute of Technology Kanpur
  • Clayton Shepard, Rice University
  • Lixin Shi, Massachusetts Institute of Technology
  • Ashish Vulimiri, University of Illinois Urbana Champaign
  • Sangki Yun, University of Texas Austin
  • Mariya Zheleva, University of California Santa Barbara
  • Hongi (“James”) Zheng, Stanford University
  • Yibo Zhu, University of Texas Austin

Summer 2012

  • Aakanksha Chowdhery, Stanford University.
  • ABM Musa, University of Illinois at Chicago.
  • Anand Padmanabha Iyer, University of California, Berkeley.
  • Chi-Yao Hong, University of Illinois at Chicago.
  • Christopher Riederer, Columbia University.
  • Chun-Te Chun, University of Washington.
  • Daehyeok Kim, University of Texas, Austin.
  • Guatum Kumar, University of California, Berkeley.
  • Hongqiang (Harry) Liu, Yale University.
  • Hyeontaek Lim, Carnegie Mellon University.
  • Luis D. Pedrosa, University of Southern California.
  • Mikhail Rybalkin, Steklov Mathematical Institute.
  • Parya Moinzadeh, University of Illinois, Urbana-Champaign.
  • Peng Sun, Princeton University.
  • Rishabh Iyer, University of Washington.
  • Robert Likamwa, Rice University.
  • Seungyeop Han, University of Washington.
  • Vijay Adhikari, University of Minnesota.
  • Virajith Jalaparti, University of Illinois, Urbana-Champaign.
  • Zengbin Zhang, University of California at Santa Barbara.

Summer 2011

  • Xuan Bao, Duke University
  • Apurv Bhartia, University of Texas Austin
  • Anuj Kumar, Carnegie Mellon University
  • Patrick Colp, University of British Columbia
  • Eduardo Cuervo Laffaye, Duke University
  • Qingxi Li, University of Illinois Urbana Champaign
  • Brent Longstaff, University of California Los Angeles
  • Radhika Mittal, Indian Institute of Technology Kanpur
  • Ardalan Amiri Sani, Rice University
  • Lenin Ravindranath Sivalingam, Massachusetts Institute Technology
  • Tingxin Yan, University of Massachusetts Amherst
  • Xia Zhou, University of California Santa Barbara

Summer 2010

  • Sara Alspaugh, University of California Berkeley
  • Colin Dixon, University of Washington Seattle
  • B. V. V. Sri Raj Dut, Indian Institute of Technology Kanpur
  • Daniel Halperin, University of Wasington Seattle
  • Srinivas Krishnan, Univ of North Carolina at Chapel Hill
  • He Liu, University of California San Diego
  • Justin Manweiler, Duke University
  • George P. Nychis, Carnegie Mellon University
  • Radhika Niranjan Mysore, University of California San Diego
  • Zhiyun Qian, University of Michigan
  • Eric Rozner, University of Texas Austin
  • Bo Tan, University of Illinois Urbana-Champaign

Summer 2009

  • Ashok Anand,  University of Wisconsin
  • Mohammad Reza Alizadeh Attar,  Stanford University
  • Aruna Balasubramanian,  University of Massachusetts Amherst
  • Dae-ki Cho, Graduate Student, University of California Los Angeles
  • Hossein Falaki,  University of California Los Angeles
  • Ang Li,  Duke University
  • Rohan Narayana Murty,  Harvard University
  • Radhika Niranjan Mysore,  University of California San Diego
  • Anh M. Nguyen,  University of Illinois – Urbana Champaign
  • George P. Nychis,  Carnegie Mellon University
  • Ki-Woong Park,  KAIST
  • Abhinav Pathak,  Purdue University
  • Swapnil Patil,  Carnegie Mellon University
  • Hariharan Rahul,  Massachusetts Institute of Technology
  • Shravan Rayanchu,  University of Wisconsin
  • Joshua Reich,  Columbia University
  • Alan C. Shieh,  Cornel University
  • Janani Sriram, Dartmouth University
  • Eeyore Wang,  Carnegie Mellon University

Summer 2008

  • Nilanjan Banerjee, University of Massachusetts Amherst
  • Mudit Jain, Indian Institute of Technology
  • Zhichun Li, , Northwestern University
  • Murtaza Motiwala, Georgia Institute of Technology
  • Patrick Verkaik, University of California San Diego
  • Ying Zhang, University of Michigan
  • Zheng Zhang, Purdue University

Summer 2007

  • Aruna Balasubramanian, University of Massachusetts Amherst. Vehicular Wi-Fi networking
  • Dhiman Barman, University of California Riverside. IPTV management
  • Xu Chen, University of Michigan. Dependency graph analysis in enterprise networks
  • Brent Couvrette, Woodinville High School. Game bandwidth estimation
  • Abhinav Jain, Indian Institute of Technology, Kanpur. Internet connectivity in Microsoft’s shuttle system.
  • Vaishnav Janardhan, Columbia University. Datagram Congestion Control Protocol (DCCP) implementation on Windows.
  • YongChul Kwon, University of Washington. Measuring and monitoring tools in Windows Live platform.
  • YonugKi Lee, Korea Advanced Institute for Science & Technology (KAIST). Game topological analysis
  • Lindsey Poole, Princeton University. Netdiff for ISP performance comparison
  • Ramya Raghavendra, University of California San Diego
  • Nilendu Sekhar, Indian Institute of Technology Kanpur. Enterprise network management

Summer 2006

  • Francisco Alvarez Cavazos, ITESM – Monterrey, Mexico.
  • Krishna Ramachandran,  University of California Santa Barbara. Enabling group communications in wireless mesh networks
  • Lun Li,  California Institute of Technolog. Generalizing fault detection in enterprise networked applications
  • Nikitas Liogkas,  University of California Los Angeles. Self-diagnosing faults in web browsers
  • Rohan Murty,  Harvard University. Providing wireless access point functionality using desktop machines
  • Srikanth Kandula,  Massachusetts Institute of Technology. Diagnosing faults in enterprise networks
  • Tulika Garg, Undergraduate, Indian Institute of Technology, Roorkie. Implementing the Mesh Connectivity Layer (MCL) in QualNet
  • Vladimir Brik,  University of Wisconsin. Self-diagnosing network faults in WiFi clients
  • Yuvraj Agarwal, University of California San Diego.

Summer 2005

Summer 2004

  • Manish Anand, University of Michigan. Comparison study of 802.11 and 802.16
  • Ranveer Chandra, Cornell University. Fault diagnosis in infrastructure wireless networks.
  • Pradeep Kyasanur, University of Illinois, Urbana Champion. Enhancing wireless mesh networks by using a separate control channel.
  • Ananth Rajagopala-Rao, University of California, Berkeley.
  • Sriram Ramabhadran, University of California, San Diego. Internet measurement
  • Sreedhar Veeravalli, Undergraduate, Indian Institute of Technology, India. Worked on TCPScope, a tool to analyze performance of TCP flows.
  • Can Vuran, Ph.D. Candidate, Georgia Tech. Worked on measurements of directional antennas.

Summer 2003

  • Ashwin Baharambe, Carnegie Mellon University. Internet gaming
  • Ranveer Chandra, Cornell University. Native WiFi and fault diagnosis in infrastructure wireless networks
  • Dejan Kostic, Duke University. Light-weight distributed failure notifications (Fuse)
  • Ananth Rajagopala-Rao, University of California, Berkeley. Trouble-shooting wireless mesh networks
  • Amit Saha, Rice University. Developing tools for measuring corporate wireless networks
  • Maneesh Varshney, University of California, Los Angeles. Neighbor location determination and MAC with directional antennas

Summer 2002

  • Ranveer Chandra, Cornell University. MultiNet and placement of Internet TAPs in wireless mesh networks
  • Kyle Jamieson, Massachusetts Institute of Technology. Bandwidth Sharing in Neighborhood Meshes
  • Karthik Lakshminarayanan, University of California, Berkeley. Worked on measurement of broadband networks

Summer 2001

  • Eugene Shih, Massachusetts Institute of Technology. Hardware and systems aspects of the Universal Communicator.
  • Kunwadee Sripanidulchai, Carnegie Mellon University. Peer-to-peer system for sharing Web content and on-demand streaming media content

Summer 2000

  • Anand Balachandran, University of California San Diego.
  • Li Li, Cornell University. Power conserving algorithms in ad hoc sensor networks
  • Allen Miu, Massachusetts Institute of TechnologyMobility management within The CHOICE Network and its deployment.
  • Shoamin Wang, Massachusetts Institute of Technology.Worked on Location Determination (WISH) and StudioMIT

Research Themes

Our research is focused on the following four broad themes. Each theme has numerous projects, and some projects span multiple themes. A partial list of current and past projects is available.

Network Verification

As we move from software on disk (e.g., Office) to Software-as-a-service delivered over the network (e.g., Ofice365) it is imperative that network down times not diminish service availability. Network verification seeks to guarantee correct operation of our data center and core networks by leveraging work in formal methods for programs. Despite the presence of cables and routers, a network can be viewed abstractly as a “program” that takes packets from the input edges of the network and outputs packets to the output edge.

This leads to a broad research agenda: building tools that are the equivalents of testers, static checkers, and compilers for Microsoft networks.  New research is required because differences in the networking domain require rethinking classical verification tools (e.g., model checking, symbolic testing) to produce new concepts. At MSR, we have built four tools including SecGuru (used operationally within Azure), NetSonar (aspects of which are in Autopilot), Batfish (which can predict the effect of routing configuration changes), and Network Optimized Datalog (which can check reachability across firewalls and load balancers). This is joint work between the MNR and RiSE groups, various network product teams, and external researchers in Stanford and UCLA.

In ongoing work, we are 1) improving the scalability of reachability checks by leveraging symmetries in data center topologies; 2) improving the speed of configuration change analysis by decomposing and modularizing the analysis logic into smaller chunks; and 3) proving correctness under all topologies and route announcements through symbolic execution of configurations.

Technology Policy

Public communications networks, such as those delivering mobile and wired broadband Internet access to homes and businesses, are typically subject to a high degree of regulatory oversight. Consequently, the policies that national governments enact have a big impact on how our customers experience our products, influencing how fast and available their connections are and how much they cost.

MNR technology policy efforts give researchers a clear understanding of policy perspectives, opportunities and constraints, and in coordination with LCA, bring world-leading technical knowledge into the policy-making arena. Examples of focus areas for MNR technology policy include rules for use of wireless radio frequencies (spectrum), and rules protecting networked services (such as O365, Bing, Skype and other Microsoft products) from being impaired by network operators (network neutrality).

    • Spectrum: Every Windows device now relies on some form of wireless connectivity, and many – such as the HoloLens, Band, and most Surfaces – assume the availability of connections based on Wi-Fi or Bluetooth protocols. These protocols are built to work on “unlicensed” spectrum bands – frequencies that can be freely used without requiring permission or payment, as long as the device shares the spectrum appropriately with other users. MNR work develops novel sharing techniques and future applications of both unlicensed and licensed spectrum bands, supporting LCA advocacy for allocation of new bands to such purposes. It also informs regulatory efforts to ensure appropriate sharing of unlicensed bands.
    • Network neutrality: Every Microsoft service ultimately relies on a network operator to connect to the customer. In most countries, the communications regulatory framework remains rooted in a legacy industry model of services provided directly by network operators. The evolving model of network-independent services, like ours, delivered “over the top” of operator networks, is motivating a transition to new rules to address questions such as whether networks may impair or charge over-the-top service providers, whether and how such “over-the-top” services should be regulated, and the extent to which network operators should be deregulated. MNR work focuses on the impact that evolving network architecture has on the need for new rules as well as the creation of partnership opportunities with network operators.

Optical Networking

Design and operations of today’s networks decouples the physical layer from higher layers—to higher layers everything is an Ethernet port, irrespective of the physical media underneath. This decoupling makes it hard to diagnose failures, manage risk (e.g., multiple IP-level links may traverse the same physical media), debug degradation of packet delivery (e.g., corruption), or modulate transmission speed based on physical layer characteristics. The decoupling may have made sense in a world with diverse physical layers, but with the convergence of the physical layer to optics, we believe it is time to revisit it.

We are pursuing two threads of research. First, we are developing techniques to characterize the physical layer and correlate its performance to that of packet delivery. To enable this analysis, we are mining optical data from Microsoft’s wide area network (WAN) and data center networks. Our analysis is uncovering key insights such as fibers cuts are not the leading cause of WAN faults (equipment failures are), the level of optical power overprovisioning in WANs is such that data transmission speeds can be safely increased by over a third, and low receive power is a common cause of packet corruption inside data centers.

Second, we are exploring radical cross-layer network designs. For the data center, we are focusing on free-space optics and the use of DMDs (digital micromirror devices, which are pervasive in projectors today) as the basis for a completely flat interconnect with high fanout and fast (10 microsecond) switching. For WANs, we are focusing on cross-layer traffic engineering, that is, a system that jointly and dynamically decides the routing of wavelengths and packets. Since commodity hardware does not enable us to prototype such ideas, we are also developing an FPGA-based platform for programmable optical transceivers.

RDMA in Large Scale Data Center Networks

Modern datacenter applications demand high throughput (over 40Gbps) and ultra-low latency (less than 10 microseconds) from the network. At the same time, the brutal economics of the cloud services market dictates that CPU overhead should be minimized. Standard TCP/IP stacks cannot meet these requirements: e.g. the single hop latency of a production TCP stack can be over 15 microseconds, and to saturate a 40Gbps link, the stack can consume 15-20% CPU cycles. Remote Direct Memory Access (RDMA) can provide low latency, and high throughput by bypassing the host networking stack for data transfer operations. On IP-routed datacenter networks, RDMA is deployed using RoCEv2 protocol, which relies on Priority-based Flow Control (PFC) to enable a lossless (i.e. no congestion drops) network.

However, PFC can lead to poor application performance due to problems like head-of-line blocking and unfairness. To alleviates these problems, we have designed DCQCN, an end-to-end congestion control scheme for RoCEv2. To optimize DCQCN performance, we build a fluid model, and provide guidelines for tuning switch buffer thresholds, and other protocol parameters. Our experiments show that that DCQCN dramatically improves throughput and fairness of RoCEv2 RDMA traffic. DCQCN is implemented in Mellanox NICs, and is being deployed in Microsoft’s datacenters.

TIMELY, a protocol put forth by Google is a parallel effort to DCQCN. It aims to solve the same problem, but uses delay as a congestion signal (like TCP Vegas).

Another way to think about DCQCN and TIMELY is that these congestion control algorithms represent a new design point in the age-old tussle between fast response and stability. They rely on PFC to offer fast response (i.e. avoid packet drops) to short-term congestion, while relying on conventional, (ECN or delay-based) based congestion control to provide long-term stability.


Datacenter Networking & Performance Optimization of Cloud ServicesWe are pursuing a multi-year cross-lab research program that focuses on producing the next generation data center networking and services. We are experimenting with radical new designs in network architecture, programming abstractions, and performance management tools. We care about inexpensive future-proof networking inside the data centers, between globally distributed data centers and to the data centers. Our research includes several projects the cut across various systems and networking research areas that are being pursued in collaboration with Microsoft’s Global Foundation Services Team, Windows Azure Team, Bing Team, and the Management Solutions Division.

Mobile Computing & Software ServicesWe are pursuing a variety of mobility-related projects: studying how the cloud can enhance the user experience on mobile devices (HAWAII); understanding how people use smartphones and the performance characteristics of 3G networks (3GTest & Diversity Studies); building systems to enhance smartphone performance, functionality, and battery lifetime using code offload (MAUI); building infrastructure to enable mobile social applications (Virtual Compass); and enhancing mobile device sensors by making their sensor readings trustworthy. In the software services arena, we are pursuing a variety of systems to simplify building scalable and geo-distributed services (PRS/Centrifuge, Volley, and Stout). Another area of emphasis is home networks, where we are pursuing network diagnosis services for the home (NetMedic & NetClinic), as well as new services and abstractions for easily building networked applications for the home (HomeOS).

Continuous Hands-free Mobile InteractionWhen combined with high-resolution touch-enabled displays, web access has proven a killer application. Playing games, reading the news or watching YouTube can capture the attention of users for extended periods many times a day. However, if the user has limited attention or the relevant tasks are short and happen many times an hour, e.g., making an appointment, adding a song to a playlist or checking on a bus, pulling the phone out of your pocket for an immersive experience is cumbersome. The newly launched Continuous Mobile Interaction project is developing usages, devices and systems to make such lightweight but frequent actions easy to do. Current efforts are along several directions. (a) an always-available speech accessory, and (b) developer support for natural-language interaction (c) platform for multi-modal interaction in moving vehicles, and (d) an always-on visual cognition engine

Cognitive Wireless NetworkingThe 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. We are revisiting “classical” wireless networking problems and designing new solutions that incorporate and build upon recent advances in software and hardware technologies. Of interest lately has been our research solutions to problems in white space networking (the KNOWS project). We are working with ploicy makers, business units and acdemia to address the societal needs for providing inexpensive broadband connectivity everywhere.

Enterprise Network Management & ServicesWe are pursuing several different projects in this area. In particular, NetHealth is a network management research program in which end-hosts cooperatively detect, diagnose, and recover from network faults. Unlike existing products we take a end-host centric approach to gathering, aggregating, and analyzing data at all layers of the networking stack for determining the root cause of the problems. NetHealth includes several on-going projects in the wireless and wired space that are being pursued in collaboration with Microsoft’s Management Solutions Division and Microsoft’s Unified Communications Group.

Product Contributions

We strive to find a balance between long term research and product impact.  You may know about our research from the papers we publish and the talks we give, here we share with you a few examples of the broad impact we have had on Microsoft products.

Assorted Microsoft product logos

Our Big Hits

  • Microsoft’s Wide Area Software Defined Network (implements a centralized traffic engineering system that has led to an improvement of the inter-DC WAN bandwidth utilization from 40% to 90%+, thus saving us millions of dollars annually)
  • XBOX One Wireless Controller Protocol (a high throughput, low latency , energy efficient Microsoft propriety protocol between the XBOX One console and controllers. It has won accolades of mainstream press as the best controller in the gaming marker)
  • Windows Azure Full-Bisection Bandwidth Datacenter Network (hailed as one of the most significant recent advances in computer science, our design led to an 80x improvement in dollars/Mbit/sec over previous designs. It is now the architecture of choice for all of Microsoft’s Datacenters. It enabled technologies like the highly-scalable Windows Azure Flat Network Storage)
  • Windows Azure Software Load Balancer (reduced cost by a factor of 15 [$60K versus $1M] by removing dependence on expensive hardware load balancers and improved cloud manageability. This fully configurable load balancer is used by both Azure and Bing)
  • Windows Firmware TPM (enabled Microsoft to offer the widely used BitLocker and DirectAccess features and a new security feature, Virtual Smart Cards, in the Windows 8 RT and Windows 8 Phone)
  • XBOX Live Service Graphs (reduced performance diagnostics in large-scale enterprise & Data Center networks from days to minutes helping meet customer SLAs. XBox Live is the first Microsoft cloud service to use use this network performance diagnosis technology)
  • Windows Network Virtualzation (enabled Windows to provide seamless connectivity between Microsoft’s Data Centers and customers’on-premise networks. Our design heavily influenced the Hyper V network virtualization feature that ships in Windows Server 2012)
  • Windows Virtual Wi-Fi (enabled Windows features like range extension, concurrent corporate and guest access, and Internet gateway using a single Wi-Fi card. Before becoming a product, our prototype was downloaded several 100,000s times becoming the top three most popular MSR software download)
  • TCP for Data Center Networking (improved performance of Data Centers networks without incurring cost for expensive hardware switches. It is implemented in our core networking stack and deployed in our Data Center properties)

Details about these and our other product contributions are provided below.

Cloud and Enterprise Division (Azure, Servers, Visual Studio,...)

Microsoft’s Wide Area Network – Architecture & Management Software (2013-14)Increases the inter-DC WAN utilization from 40% to 90%+

  • Previously inter-DC WANs running MPLS achieved only 40% average utilization. We built a logically centralized traffic engineering system that attains 90%+ average utilization while meeting different service policies. This saves tens of millions of dollars in WAN expense each year. Our paper describing an early (pre-production) version of this system was published in SIGCOMM 2013. Our design and technologies have been adopted and put into production by Windows Azure Networking and Microsoft’s Global Network Services.

AutoPilot’s Network-state Management Service (2014)Dramatically simplifies network management app development and operations while maintaining network-wide SLA

  • DC network management applications are complex and sophisticated, usually requiring years to design, develop and deploy. Running multiple such applications is challenging as they may conflict with one another and their collective actions can impair network operation. The Autopilot Statesman service that we developed, simplifies application development by shielding apps from low-level interactions with devices. By offering a novel network state model, Statesman enables apps to operate independently while maintaining network-wide safety. Our technology has been deployed in all Autopilot managed datacenters.

Windows Azure ZKaaS (ZooKeeper as a service) (2014)A multi-tenant coordination cloud service that uses open source Zookeeper

  • We worked closely with the AutoPilot team to build a multi-tenant layer on top of ZooKeeper that can be deployed and monitored by their software. The coordination service underneath runs multiple ensembles which can execute arbitrary requests from authenticated tenants. Although the ensembles are shared, to the user it seems as if they are running a dedicated ensemble. In future releases tenants will receive concrete compute resources tokens with full performance isolation.

Windows Azure Autopilot NetInsight (2013-14)End-to-end measurement and analysis tools that run automatically and vastly improve the accuracy of WAN fault localization.

  • Localizing performance faults on WAN is difficult due to the plethora of routers and paths between DCs. We developed a system that accurately localizes faults to a specific router interface among thousands of candidate routers and paths. Compared to the state-of-the-art SNMP-based system, our system, called NetInsight, reduces the number of false positives by two orders of magnitude.

Network Virtualization for Hybrid Clouds (2010-12)Enabled Windows to provide seamless connectivity between Microsoft’s Data Centers and customers’on-premise networks 

  • Cloud computing provides as much compute and storage as needed, where needed. However, large enterprises require hybrid clouds: private Data Centers that only send overflow computing to the cloud. The challenge is to allow competing enterprises to use the same public Internet addresses on a shared Azure network without interference, and to also have seamless connectivity back to the enterprise network. We designed new mechanisms with separate logical and physical Internet addresses in V-Net thus allowing it to efficiently virtualizes Azure’s network; V-Net allows fast delivery of Internet packets, rapid migration of Virtual Machines with low overhead, and performance isolation V-Net’s design has heavily influenced the Hyper-V network virtualization feature that ships in Windows Server 2012.

Visual Studio Energy Modeler & Profiler (2012)

  • 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 MobiSys 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.

GreenUp (2011-12)Delivers significant power and monetary savings for enterprise customers by enabling seamless remote access to sleeping desktop machines 

  • Enterprise can save significant amounts of power by letting idle desktop machines go to sleep (S3). This behavior has been the default setting in Windows desktop for many years. However, users and system administrators often override this because they may need to access the machines remotely. Current wake-on-Lan technique are cumbersome, and do not always work on complex networks. We designed and built a wakeup service (“GreenUp”) that works transparently – any time the user tries to remotely access a sleeping machine, it seamlessly wakes it up. This encourages users to save power. GreenUp scales up to large, complex corporate networks, by using a novel distributed leader election

Fully Configurable Windows Azure Software Load Balancer (2011)Reduced costs by a factor of 15 by removing dependence on hardware load balancers and improved cloud manageability as well 

  • Hardware load balancers are traditionally used as the front tier of clouds to distribute incoming traffic to servers. We designed a scale-out software load balancer that can dynamically scale from 1 Gbps to 100 Gbps. To the best of our knowledge this was the first software load balancing solution in industry. Our solution reduces costs by a factor of 15x ($60K versus $1M) compared to hardware load balancers, and allowed more flexibility and easier management as well. To compete with the speed of hardware, our design made clever use of existing routing protocols and the Windows networking stack. Our design is now the load balancer of choice for Azure and Bing.

Full-Bisection Bandwidth Datacenter Networks (2009-10)Servers in a datacenter are no longer limited by the network that connects them

  • For cloud services the three key elements to success are: cost of infra-structure, availability, and response time. Conventional datacenter design advocated by established networking vendors does poorly on all three measures. We designed and validated a new datacenter network architecture that excels in all three metrics; in particular, it provides an 80X improvement in dollars/Mbit/sec over existing designs while providing uniform high capacity between servers, performance isolation between services, and dynamic resource allocation across large server pools. Our design is now the network architecture of choice for all of Microsoft’s datacenters including those managed by XBox, Bing and Azure.. Our initial SIGCOMM 2009 paper (VL2: A Scalable and Flexible datacenter Network) was republished by the Communications of the Association for Computing Machinery (CACM) in 2011 as one of the most important research result in Computer Science in recent years; it was cited as “a great example of rethinking networking from scratch, while coming full circle to work with today’s equipment.”

TCP Analyzer (2010)Enabled Microsoft Network Monitor to provide deeper insights into the working of Internet’s Transport Control Protocol 

  • We designed and built a plugin (called an “expert”) for Microsoft Network Monitor (NetMon) that helps analyze TCP traces. It uses several sophisticated heuristics to answer the key question “what limited the throughput of this TCP connection”. Apart from answering this question, the plugin also allows the user to visualize the connection in a number of different ways. Our plugin has been downloaded thousands of time, and is one of the most popular NetMon “experts”.

Operating Systems Engineering (Windows, Phone, Windows Embedded)

Data Sense Bandwidth Attribution Technology (2012)

  • We built a technology that tracks cellular and Wi-Fi data consumption for individual apps and OS components, and displays it in an intuitive UI. A challenge we had to overcome was to accurately attribute data consumption across the numerous APIs and OS services that mobile apps use, and to do so in a lightweight manner. See the original technology demo video (Aug. 2011).

Mobile Input Services & Technology (2012)

  • Typing intelligence: We enabled Windows Phone to scale their typing intelligence solutions (hit-target resizing, spell correction, candidates-on-demand, etc.) to over 50+ languages, including new languages such as Latin Hindi.
  • WordFlow Keyboard User Adaptation: We helped with a feature that allows Windows Phone keyboard to adapt to the users’ language and offer their words as completions and next word predictions.
  • Keyboard Input Architecture: We helped revise the input architecture and created a new edit buffer to facilitate new features such as user adaptation, multilingual editing within the same message, and seamless multi-modal integration.

Firmware TPM Emulator (2012)

  • We delivered the TPM driver and firmware TPM simulator. The development team used our simulator to develop & test important security features even before the vendors provided them the actual devices. A better description of our contribution is provided under “Windows”.

AppInsight to the Application Compatibility Team (2012)

  • We delivered a customized version of our application analytics tool for performance testing and failure analysis of the top WP marketplace applications on various hardware and software SKUs. The development team run this tool routinely on third-party apps and they estimate to have reduced the time spent on app. failure analysis by a factor of 2 to 4. The first paper (AppInsight: Mobile App Performance that describes our system appeared in OSDI 2012.

Wireless Optimizations in Windows 8 (2011-12)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.

Network Quality of Service for Virtual Machines (2011-12)Enabled Windows 8 to provide predictable networking to high-value cloud services

  • We helped design and evaluate a mechanism to adaptively control the network usage of a Virtual Machine (VM), analogous to equivalent controls that existed for CPU and memory. Our design includes a feedback loop that ensures VMs receive network bandwidth that is proportional to their share and that spare bandwidth is allocated among VMs that need it. OurVM Rate Shaper shipped in Windows 8.

Support for Security Features in Windows ARM (2011-12)Enabled widely used security features (BitLocker, DirectAccess, Virtual SmartCards) on Windows RT and Windows Phone

  • Many enterprises mandate the use of crucial security features such as BitLocker and Direct Access on their employees mobile devices. These Windows features require Trusted Platform Module (TPM) chips that are normally part of the hardware of modern computers. Unfortunately, Windows 8 and Windows Phone have low power versions that run on ARM chips which do not have standard TPM hardware; instead, ARM offers an alternate hardware security platform called TrustZone. We worked with the Windows team and helped deliver a reference implementation of a firmware emulation (of the missing TPM chip) we called fTPM that leverages ARM’s hardware. Microsoft delivered fTPM to our SoC partners who incorporated it in their latest firmware releases.This then enabled Microsoft to offer BitLocker, Direct Access, and a new Windows 8 security feature, Virtual Smart Cards, in the Windows 8 RT and Windows 8 Phone releases.

Antenna Placement on Windows Tablet (2011-12)Enabled best-in-class Wi-Fi network connectivity & performance

  • 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 wereincorporated in the final design of Windows 8 tablets.

Datacenter TCP (2010-12)Improved network performance in Data Centers with inexpensive switches 

  • We designed a new variant of TCP, called Datacenter TCP (DCTCP) to address congestion control issues in datacenter networks. DCTCP leverages Explicit Congestion Notification (ECN) and a simple mOLti-bit feedback mechanism at the host to reduce application latencies by overcoming network impairments such as queue buildup, buffer pressure, and incast. DCTCP was designed in close collaboration with the Windows Networking Team and itships in the Windows 8 networking stack. The initial paper (Datacenter TCP) was published in SIGCOMM 2010.

Virtual Wi-Fi (2009)Enabled Windows to connect to multiple WLANs simultaneously and offer range extension, concurrent corporate and guest connection, and Internet gateway features

  • 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 mini-port 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.

Network Bandwidth Estimation (2004-05)Enabled Windows to offer a better media streaming experience over Wi-Fi

  • We developed a technique (“Probe-Gap”) to estimate the capacity and the available bandwidth of network paths based on end-point measurements. The problem was particularly difficult for cable modems and Wi-Fi networks because they do not have point-to-point links. For example, they employ mechanisms such as token bucket rate regulation; non-FIFO scheduling, and multiple rate. The initial paper (Bandwidth Estimation in Broadband Access Networks) describing the problem was published in IMC 2004. Probe-Gap first shipped in Windows XP.

NDIS WLAN extensions in Windows 2000, Windows XP, Vista & Windows 7Elevated Wireless LAN connectivity to a premier consumer networking technology in Windows

  • We designed the (first set of) NDIS WLAN OID for Windows 200 and beyond. Prior to our contribution Windows exposed a wireless LAN network adapter as an Ethernet network adapter. We enhanced the programming interface exposed by the Network Device Interface Specification (NDIS) and WinSock which then enabled novel wireless-aware and mobility-aware applications.

Applications and Services Engineering (Bing, Skype, Office, Outlook,...)

Network Failure Recovery in Data Centers (2012)NetPilot reduces the recovery time for the common Data Center network failures from a few hours to tens of minutes

  1. Handling network failures is one of the most challenging tasks for Data Center operators. Different from the conventional failure diagnosis and repair process which requires significant human intervention, Our NetPilot technology mitigates failures by deactivating or restarting the suspect network devices without the need for knowing the exact root causes. By enabling automatic failure mitigation, Netpilot dramatically reduces the recovery time for common network failures. Our initial paper (NetPilot: Automating Datacenter Network Failure Mitigation) describing this system was published in SIGCOMM 2012 and we shipped as part of the Bing Metallica Release in June 2012

Improving Page Load Time of Bing Searches (2012)Faster load times leads to better user experience

  1. We performed a comprehensive analysis of the page load time in Bing to help uncover and explain strange effects such as Page Load Time (PLT) increase during off-peak hours and the impact of browser population and query type. These insights were used to develop a more precise and detailed alerting tool for PLT degradation. We documented some of our learnings in a SIGCOMM 2013 paper (A provider-side view of Web Search Response Time).

Onset-of-congestion Signaling (2012)Our congestion prediction technology enables mitigation strategies that lead to better application performance

  1. In distributed file systems, when one storage node is congested both read- and write- traffic can be steered to other replicas and other nodes with empty space. If the on-set of such congestion is detected quickly, one can avoid needless queuing lags and improve overall store throughput. We helped design a predictor that uses current load and historical performance to predict the congestion status of storage nodes in Cosmos early. As a side-benefit, this also serves as a measure of application-perceived capacity of the distributed storage layer and a monitor of current usage and hotspots. Our technology is shipping in Cosmos clusters in Bing since December 2011.

ReOptimizer for Data Parallel Computing (2011)This technology significntly reduced the response times of large jobs in our Data Centers

  1. Performant execution of data-parallel jobs needs good execution plans. Certain properties of the code, the data, and the interaction between them are crucial to generate these plans. Yet, these properties are difficult to estimate due to the highly distributed nature of these frameworks. We built the first reoptimizer for data-parallel jobs. It collects certain code and data properties by piggybacking on job execution and adapts execution plans by feeding these properties to a query optimizer. Our technology shipped in Bing’s Cosmos clusters in December 2011. and it has significantly improved the response times on production jobs.

Mitigating Outliers in Data Parallel Jobs (2009)

  1. Laggard tasks signicantly prolong the completion time for data-parallel jobs. The causes for such outliers include run-time contention for processor, memory and other resources, disk failures, varying bandwidth and congestion along network paths and imbalance in task workload. We buit a system that monitors tasks and culls outliers by restarting tasks, network-aware placement of tasks and protecting outputs of valuable tasks. The result was a significant improvement of job completion time. Our technology is in production use across all of the Cosmos clusters in Bing since May 2010.

NetTrace (2009)

  1. To answer some of the basic questions about real workloads we built NetTrace, a network tracing service for large data center clusters. This service collects low level networking logs (socket-level) and uploads to COSMOS. Processing the data yields a much better understanding of the traffic patterns of operational workloads and also helps diagnose whether the network or the application is to blame for poor performance. NetTrace ships as an autopilot service in Bing since 2009. We also shipped an analysis suite and Bing continues to invest in NetTrace, in their June 2012 release, they expanded the types of data captured, lowered resource consumption of the logger and are in the process of rolling it out as an always-on service.

DNS Query Time Optimization (2008)

  1. We conducted a series of experiments to measure the DNS query resolution time for Bing. Based on these measurement we came up with a set of improvements to our DNS query chain. Worked closely with Bing we deployed these improvements and in the process reduced the median DNS query time by more than half of previous amount. More importantly, the 95th percentile was cut in half.

Scalable and Consistent Caching (2008)Enabled MSN web properties to better handle spikes in load (flash crowds)

  1. The MSN Publishing Platform serves billions of web pages a month. As they grew, scalability bottlenecks started to show up in their previous architecture. TheScalable and Consistent Caching (SCC) technology allowed them to solve these bottlenecks while maintaining the strict consistency semantics that content publishers expect, such as adding breaking news to a web page and all viewers seeing the updated content.

Partitioning and Recovery Service (2008)Enabled Live Mesh (now SkyDrive) backend cloud services to scale resiliently

  1. The Live Mesh data center services need to partition user data across a large number of servers. We designed and built the Partitioning and Recovery Service (PRS), which became their mechanism for doing this. The PRS made the development of the server code easier by providing a number of novel properties, such as strong consistency for soft state and guaranteed notifications to trigger state republishing. Microsoft’s Live Mesh product won CNET’s best technology innovation/achievement award.

Managing Shared Credential Vulnerabilities (2008)The technology behind Microsoft Forefront risk analysis and mitigation planning feature

  1. We developed a technique which evaluates the risk to an organization based on patterns of user privilege and access. Attackers use accounts to compromise machines and use machines to compromise accounts. In the absence of explicit management to mitigate this risk, growth in jumping from one machine to another via a compromised account is exponential. In a test, corroborated by our graph-based analysis, we found that over 70% of the machines investigated yielded at least one account that granted control over 100 other machines on the next hop. Our system performs static analysis and generates pre- and post-incident reports for planning risk mitigation strategies. We shipped our technology in the Access and Security Division’s (ASD) ForeFront Product Suite.

Devices and Studios (XBox, XBox Live, Hardware, Surface...)

XBOX One Wireless Controller Protocol (2013-14)The wireless protocol between the XBOX One controllers and the console

  • We designed the wireless protocol which XBOX accessories use to connect with the XBOX one console. The protocol enables high-throughput and low-latency wireless communication, which is required for gaming and media traffic. Using this protocol the XBOX One can support more number of accessories, with higher throughput, lower latency than any known gaming or home entertainment system that currently exists in the market.

Service Graphs for Large-Scale Network Diagnostics (2012)Helps meet customer service level agreements (SLAs) by quickly identifying faltering components, reducing down time from days to minutes

  • One of the challenge for cloud vendors is to avoid network and system failures that can potentially cripple business users. It is an unfortunate fact that sometimes performance failures do occur and users complain about poor response times. Localizing the source of performance problems in large enterprise and cloud networks is a hard problem because each request depends in complex ways on numerous hardware and software components. We devised a new method to identify these dependencies and record them in an Inference Graph which we then used to quickly and accurately localize the failure to a small set of possible culprits. Our SIGCOMM 2007 and OSDI 2008 papers show how to narrow down the set of potential dependencies by 100x – 10000x. Our inference graph technology was adopted by Microsoft Services Engineering Team and shipped as Azure Service called “Service Call Graph 1.0”. Network performance faults that previously took hours or days to diagnose can now be diagnosed in matter of minutes.


MNR works with academic institutions in a number of different ways. We sponsor a number of ACM and IEEE conferences; Our researchers serve on steering and program committees of academic conferences and workshops; we serve on editorial boards of prestigious journals; Via the Hawaii Academic outreach program, we support mobile computing courses and research at several universities; we invite colleagues from academia to visit us and we host events that provide a forum to brainstorm about new research.

Founded / Co-Founded

Sample Professional Service


  • Program Co-Chair  USENIX NSDI
  • Program Chair HotMobile
  • Steering Committee: MobiCom, MobiSys, DySPAN, MCS Workshop, ISWC, CoRoNet Workshop, HotMobile
  • Information Director ACM SIGMOBILE
  • Editorial Board Member: MC2R, CCR, IEEE Journal on IoT, …


  • General Chair HotMobile
  • Program Committee Co-Chair: MobiCom
  • Program Committees: MobiSys, MobiCom, NSDI, SIGCOMM
  • Poster/Demo Chair: SIGCOMM
  • Steering Committee: MobiCom, MobiSys, DySPAN, MCS Workshop, ISWC, CoRoNet Workshop, HotMobile


  • General Chair: DySPAN
  • Program Committee Co-Chair: DySPAN, MobiGames
  • Program Committees: MobiSys, MobiCom, NSDI, DySPAN, SIGCOMM
  • Poster/demo/workshop Chairs: MobiSys, SIGCOMM
  • Steering Committee: MobiCom, MobiSys, DySPAN, MCS Wokshop, MobiHeld Workshop, ISWC, CoRoNet Workshop
  • Associate Editor: IEEE Transactions of Mobile Computing (2011-12)


  • Program Committees: MobiCom, NSDI, SIGCOMM, MobiSys, ICNP. MobiHeld
  • Steering Committee: MobiCom, MobiSys, DySPAN, MCS Wokshop, MobiHeld Workshop, ISWC, CoRoNet Workshop

Brainstorming Events

For a number of years we have been organizing mindswap events between researchers from industry, academia, and government. At these events we have open discussions on important research topics and the challenges ahead.  For the benefit of the community, we make videos and presentation slides from all talks available on the event’s web site. Here are the events we have organized:

    • New Results in Networking Research, Redmond, WA (Dec. 5, 2013)
    • New Directions in Wireless Systems Design, Redmond, WA (May 30, 2013)
    • New Directions in Networked Systems Design. Redmond, WA (October 31, 2012)
    • Data Analytics and the Networks that Enable Them, Woodinville, WA (June 18-19, 2012)
    • Mobile + Cloud, Westin Hotel, Bellevue, WA (June 2-3 2010)
    • Cognitive Wireless Networking, Salish Lodge, Snoqualmie, WA (June 5-6 2008)
    • High Speed TCP , Redmond, WA (February 5-6, 2007)
    • Research and Practice in Corporate/Campus Networks  Snoqualmie, WA (June 1-2, 2006)
    • Wireless Networking: Goa, India (April 7-8, 2006)
    • Self Managing Networks, Kirkland, WA (Jun 1-2, 2005)
    • Mesh Networking: Snoqualmie, WA (Press Report)  (June 23-24, 2004)

    Project Hawaii Academic Partners (2010 - 11)

    Fall 2011:

    Cambridge University, University of North Carolina, Purdue University, University of Michigan, Michigan State University, Singapore Management University School of Information Systems, Egypt-Japan University of Science and Technology, Virginia Tech University, University of South Carolina, Old Dominion University, Clemson University, Temple University, University of Utah, University of Wisconsin-Madison, University of Arkansas, University of Oregon

    Spring 2011:

    University College London, Stanford University, Duke University, University of Arkansas, University of Minnesota, University of Illinois at Urbana-Champaign, New York University, University of Massachusetts Lowell, Stony Brook University, University of Houston, University of California Santa Barbara, Ohio State University, Temple University, Purdue University, University of California Santa Barbara, University of Leipzig, Germany, Indiana University, Purdue University, Pontificia Universidade Catolica, Brasil, University of Goettingen, University of Washington

    Fall 2010:

    Singapore Management University School of Information Systems, University of Micigan, University of Maryland, University of Arkansas, University fo California at Santa Barbara, Michgan State University.

    Spring 2010:

    University of Southern California, University of Wisconsin Madison, Duke University

    Conference Support

    We have consistently supported strong conferences on mobile systems. A sampling of some conferences we have supported in the recent past

    2013MobiCom, HotMobile, S3, MobiSys, HotNets

    2012MobiSys, HotMobile, DySPAN

    2011MobiCom, SIGCOMM, MobiSys, DySPAN, NSDI, MobiCom – PhDForum

    Research Center Membership

    Research Support

    In addition to Project Hawaii Support, and an extensive University Relations Program dedicated to funding research at Universities, occasionally we too support faculty research in areas of our interests. Examples of institutes MCRC Researchers have supported in the past include:

    • University College London (Prof. Brad Karp, 2010)
    • Duke University (Prof. Romit Roy, 2009)
    • USC (Prof. Ramesh Govindan, 2009)
    • Harvard University (Prof. Matt Welsh, 2008)
    • University of Toronto (Prof. Yashar Ganjali, 2010; Prof. Stefan Saroiu, 2007)
    • Princeton University (Prof. vivek Pai, 2007)
    • UCLA (Prof. Todd Millstein, 2008)
    • MIT (Prof. Dina Katabi)
    • International Computer Science Institute Berkeley (Prof. Scott Shenker)
    • UCSD (Prof. Geoff Voelker)
    • CMU (Prof. Peter Steenkiste, 2010; Prof. Srini Seshan)
    • Columbia (Prof. Dan Rubensteini & Prof. Vishal Misra)
    • Texas A&M University (Prof. Nitin Vaidya)
    • University of California Berkeley
    • University of Maryland, College Park (Prof. William Arbaugh)
    • UT Austin (Prof. Lili Qiu)
    • University of Wisconsin-Madison (Prof. Suman Banerjee)
    • Rice (Prof. Ed. Knightly, 2010; Prof. T. S. Eugene Ng, 2007)

    Distinguished Guests

    Microsoft Research organizes an annual faculty summit in Redmond. The summit offers a unique opportunity for us to mingle with researchers in academia. In addition to this we have had the pleasure of hosting several distinguished researchers in our center as well. Here is a partial list of a few who have visited us:

      • Rodrigo Fonseca, Brown University
      • Lin Zhong, Rice University
      • Rajesh Balan, Singapore Management University
      • Romit Roy, Duke University
      • Ramesh Govindan, University of Southern California
      • Suman Banerjee, Wisconsin University Madison