Jonathan Ponniah

NSF Center for Science of Information
Computer Engineering Systems Group
Texas A&M University


I am an NSF Center for Science of Information post-doctoral researcher at Texas A&M University.

My research is in the areas of security, distributed systems, networks, and network information theory. More specifically, I work on the design of secure protocols for wireless ad-hoc networks and towards an information-theoretic understanding of networks with bidirectional data flows.

My advisor is Professor P.R. Kumar. I am also a member of the Computer Engineering and Systems Group.

I received my Bachelors and Masters in Electrical Engineering from the University of Waterloo in 2006 and 2008 respectively. I was advised by Professor Liang-Liang Xie. I received my Doctorate in Electrical Engineering from the University of Illinois Urbana-Champaign in 2013.


Address: 188 Bizzell St, Room 333A, College Station, TX, 77843-3259

Email: jonathan DOT ponniah AT gmail DOT com


  • A Clean Slate Approach to Secure Wireless Networking,
    Jonathan Ponniah, Yih-Chun Hu, and P.R. Kumar
    now publishers, Foundations and TrendsŪ in Networking: Vol. 9: No. 1, pp 1-105., August 2015


  • An Achievable Rate Region for the Two-Way Multiple-Relay Channel,
    Jonathan Ponniah, Liang-Liang Xie, and P.R. Kumar
    In preparation, available upon request.

  • A Clean Slate Approach to Secure Ad-Hoc Wireless Networking - Open Unsynchronized Networks,
    Jonathan Ponniah, Yih-Chun Hu, and P.R. Kumar
    Submitted to the Transactions on Control of Networked Systems

  • A System-Theoretic Clean Slate Approach to Provably Secure Ad-Hoc Wireless Networking
    Jonathan Ponniah, Yih-Chun Hu, and P.R. Kumar
    TCNS, IEEE Transactions on Control of Networked Systems Volume: 34, No: 1, November 2014

  • An Orthogonal Multiple-Access Coding Scheme
    Jonathan Ponniah, Yih-Chun Hu, P.R. Kumar
    CIS, Communications in Information and Systems, Volume: 12, No: 1, 2012


  • A Clean Slate Design for Secure Wireless Ad-hoc Networks - Part 2: Open Unsynchronized Networks,
    Jonathan Ponniah, Yih-Chun Hu, and P.R. Kumar
    WiOpt 2015, 13th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks, Mumbai India, May 2015

  • A Clean Slate Design for Secure Wireless Ad-hoc Networks - Part 1: Closed Synchronized Networks,
    Jonathan Ponniah, Yih-Chun Hu, and P.R. Kumar
    WiOpt 2015, 13th International Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks, Mumbai India, May 2015

  • The Two-Way Multi-Relay Channel,
    Jonathan Ponniah, Liang-Liang Xie, and P.R. Kumar
    ITW 2015, IEEE Information Theory Workshop, Jerusalem Israel, May 2015

  • An Achievable Rate Region for the Two-Way Two-Relay Channel,
    Jonathan Ponniah, Liang-Liang Xie, and P.R. Kumar
    ISIT 2008, IEEE International Symposium on Information Theory, Toronto Canada, July 2008


  • A Clean Slate Approach to Secure Wireless Networking.
    Jonathan Ponniah.
    Doctoral Thesis, ECE University of Illinois Urbana-Champaign, August 2013.

  • An Information Theoretic Framework for Two-Way Relay Networks.
    Jonathan Ponniah.
    Masters Thesis, ECE University of Waterloo, August 2008.


  • An Information-Theoretic Approach to Bidirectional Networks
    The "two-way multi-relay channel" in information theory refers to a network in which information flows simultaneously and interactively in both directions between a pair of source/destination nodes with the assistance of intermediate relay nodes. This particular channel is implicit in almost all forms of modern communication. For instance, every packet transmitted over the internet by a user, must be routed to its final destination through intermediate routers, and acknowledged by the destination upon reception. The information-theoretic approach allows the channel statistics to be completely arbitrary; the transmitted sequences of all nodes potentially influence the received sequences at each node through an unspecified probability transition matrix. The problem is to characterize the capacity region; the set of rate pairs at which information can be conveyed with perfect reliability. In the arbitrary discrete memoryless channel under consideration, there are few tools with which to work. One of these tools is the information theoretic cut-set outer-bound which determines the rate vectors not in the capacity region. This outer bound is generally not achievable with the kinds of encoding schemes known today.

  • The Two-Way Two-Relay Channel
    We consider the two-way two-relay channel. Previous work by Xie obtained an "achievable rate" (a lower bound on the capacity region) for the one-way multiple region, structurally similar to the outer-bound. We attempt to obtain the natural extension of this rate to the two-way two-relay channel. We discover that the structure of this "desired" rate region has a fundamental internal tension within it; the rates in one direction can only be obtained at the expense of the rates in the other direction. Therefore every effort to achieve this rate region fails.

    Papers: [ISIT '08]

    The Symmetric Two-Way Multiple-Relay Channel
    The internal tensions within the structure of the desired rate region cause a complete collapse of this structure when there are more than two relays in the network. Any effort to recover this rate region is realized in a series of decisions that individually favor the data rate in one direction over the data rate in the other direction. These decisions yield an encoding scheme and corresponding rate region. However, these rate regions and encoding schemes are intractable to write down. First of all, the number of encoding schemes is exponential in the number of nodes. Second, the rate region corresponding to each encoding scheme depends on the transmitted sequences and the history of decoded messages at each node. These parameters are specific to the encoding scheme and are intractable to explicitly characterize as the number of nodes becomes large. Moreover, these encoding schemes do not collectively recover the desired rate region, nor is any particular rate region universally included in another region. We discover that in a special kind of symmetric channel, the effort to recover the desired rate region is similar to the "reverse-order draft"; a process by which teams are ranked to pick players out of a common pool in the NFL draft. It turns out that the achievable region corresponding to this encoding scheme can be beautifully expressed in terms of the "reverse-order" ranking.

    Papers: [ITW '15]

    The Two-Way Multiple-Relay Channel
    We discover that all of the encoding schemes and corresponding achievable rate regions are specific realizations of a deeper structure and its underlying symmetry. The effort to recover the desired rate region ultimately creates the "ground" out of which all the particular encoding schemes and rate regions are realized. Even though each individual encoding scheme and rate region fails to recover the desired rate region, and is intractable to characterize by itself, together these encoding schemes and regions share a common ground. This ground is structurally expressed in the rank assignment, wherein each node in the network is assigned a unique rank according to a certain procedure. All encoding schemes and achievable rate regions can be represented in terms of these so called "valid rankings". Hence the achievable rate region can be completely characterized. The effort to reach the structure of the information-theoretic outer bound, though ultimately futile, creates a new structure out of the myriad ways in which the effort can be realized. This discovery opens the door to an information theory for multi-hop communication in wireless networks with multi-way data flows. For the two-way physically degraded symmetric Gaussian channel the reverse-order ranking achieves the capacity region asymptotically in the number of nodes.

  • Secure Wireless Ad-Hoc Networking
    Wireless ad-hoc networks lack a centralized controller. Hence, the nodes themselves must arrive at a consensus that accurately estimates the network topology, the feasible routes, and the corresponding transmission schedule. A protocol specifies the actions that each node must carry out, based on its internal state, to form a functioning network. A secure protocol ensures that the network retains its functionality even if adversarial nodes in the network behave in arbitrary or deliberately malicious ways. Secure protocols often inherit the legacy architecture of unsecured protocols, where any identified vulnerabilities are "patched". Unfortunately, it is impossible to know for certain whether all such vulnerabilities have been identified, or whether there are still others that have yet to be detected. As a result, the design process itself turns into an arms race between more sophisticated attacks and corresponding patches. At no point in this process is it possible to make any security guarantees.

    Closed Synchronized Networks
    We propose a "clean slate" systematic approach to secure protocol design that provides comprehensive security and performance guarantees contingent on some underlying model assumptions. The design problem is framed as the solution to a game between protocols and adversarial strategies, where the payoff of each outcome corresponds to the functionality retained by the network despite the adversarial activity. Since the adversarial nodes choose a strategy after the protocol has been announced, the max-min payoff (the "best worst case" payoff), is optimal. We propose a protocol that achieves this payoff regardless of the actions of the adversarial nodes. Moreover, we show that the protocol is actually min-max optimal; there is a saddle-point in the strategy space between protocols and adversarial strategies. Furthermore, we show that the adversarial nodes are strategically limited to either jamming or conforming to the protocol. These results assume that the legitimate nodes are both synchronized and simultaneously activated, so that no other legitimate nodes need join the network thereafter (the network is closed).

    Papers: [WiOpt'15], [FnT Ch.1-4]

    Secure Clock Synchronization
    We consider the problem of secure clock synchronization in a network with adversarial and legitimate nodes. The legitimate nodes have local clocks that are relatively affine. The relative clock parameters between each pair of nodes, the skew and offset, can be measured by an exchange of timing packets provided the nodes generate correct time-stamps. These parameters can then be disseminated to the rest of the network allowing each node to obtain an accurate estimate of a common reference clock. The problem occurs when adversarial nodes generate false time-stamps that cause inconsistent estimates of the reference clock. We propose a "consistency check" algorithm that ensures the legitimate nodes obtain consistent estimates of a common reference clock to within any desired accuracy.

    Papers: [FnT Ch.5]

    Communication in Half-Duplex, Unsynchronized Networks
    In unsynchronized wireless ad-hoc networks, the nodes must broadcast probe packets to discovery their neighbors and synchronize their local clocks. However, if the nodes are half-duplex (they cannot simultaneously transmit and receive messages), then even this tentative step will fail if two neighbors are always simultaneously in transmit mode. We create an orthogonal MAC code that guarantees any node will exchange packets of fixed length within a bounded time, provided the skews of the local clocks are also bounded.

    Papers: [CIS '12], [FnT Ch.6]

    Closed Unsynchronized Networks
    We extend the clean slate approach to closed unsynchronized networks, by incorporating the consistency check and the orthogonal MAC code into the protocol. The new protocol enables a collection of unsynchronized nodes infiltrated with adversarial nodes to form a functioning network operating at min-max optimality. Moreover, the adversarial nodes are able to cooperate fully, whereas the legitimate nodes do not know which nodes are adversarial. The protocol addresses all stages of the operation from primordial birth until the expiry of the operating lifetime.

    Papers: [WiOpt '15], [TCNS '15], [FnT 'Ch.7]

    Open Unsynchronized Networks
    We extend the clean slate approach to open unsynchronized networks where legitimate nodes can be activated at any time. We include a "merge" process in the protocol to ensure that any pair of adjacent subnetworks will periodically interrupt regular operation to broadcast probe packets and listen for the probe packets from other nodes. The problem is that adversarial nodes might exploit this process to lure adjacent subnetworks into making repeated spurious merge attempts, which are expensive with respect to the overhead and throughput loss. We show using a finite-state machine argument that the legitimate nodes will eventually merge into the same network regardless of what the adversarial nodes do. Moreover, we show that protocol operates at the min-max optimal throughput, evaluated from the birth of the last legitimate node.

    Papers: [TCNS '16]


  • An Achievable Rate Region for the Two-Way Multiple-Relay Channel
    To be presented at the graduation day talk, ITA 2016, San Diego, Feburary 2016
  • A Clean Slate Approach to Secure Wireless Networking
    Invited lecture for the ITSOC School of Information Theory, Purdue, June 2013
    [SLIDES]    [VIDEO]
  • A Clean Slate Approach to Secure Wireless Networking
    Invited talk at MIT, December 2013



    I reviewed papers in the following venues:

      IEEE Transactions on Information Theory
      IEEE/ACM Transactions on Networking
      IEEE Transactions on Wireless Communications
      IFAC Workshop on Estimation and Control of Networked Systems

Teaching Assistant

  • Digital Signal Processing

    Course: ECE 413, Summer 2007, University of Waterloo
    Professor: Oleg Michailovich
    Role: I managed this course with Prof. Michailovich. I taught the lectures when Prof. Michailovich was away, prepared weekly tutorials, and graded the homework assignments and exams.

Relevant Graduate Coursework

  • University of Illinois Urbana-Champaign:
    MATH 540: Real Analysis
    MATH 541: Functional Analysis
    MATH 561: Theory of Probability
    MATH 561: Theory of Probability II
    MATH 580: Combinatorial Mathematics
    ECE 515: Control System Theory and Design
    ECE 567: Communication Network Analysis
    ECE 534: Random Processes
    ECE 555: Control of Stochastic Systems
  • University of Waterloo:
    STAT 901: Theory of Probability I
    STAT 902/ECE 784: Introduction to Stochastic Calculus
    STAT 850: Estimation and Hypothesis Testing
    ECE 612: Information Theory
    ECE 710: Network Information Theory
    ECE 610: Broadband Communication Networks

Awards & Honors


Russian Ships Near Data Cables Are Too Close for U.S. Comfort
David E. Sanger and Eric Schmitt, New York Times, October, 2015.

Elon Musk Plans Satellite Network
Guardian, Chris Johnson, November, 2014.

Announcing the Connectivity Lab at Facebook
Facebook Press Release, March, 2014.