about me

I am a Ph.D candidate in Computer Science and Engineering at the University of South Carolina. I work with my adviser Dr. Srihari Nelakuditi and colleagues in the ARENA lab in improving wireless network system performance. I am co-advised by Dr. Romit Roy Choudhury of Duke University.

Before joining the Ph.D program, I got my MS in Wireless Network Security from USC and Bachelors in Computer Science and Systems Engineering from Andhra University, India. I am interested in developing wireless solutions which make effective use of the characteristics unique to wireless networks. Please look at my research work section on projects I have worked/currently working on. Drop me an email if you are interested in any of the work or have any questions.

Research and Publications

Controller Assited Packet Scheduling (CAPS) [pdf]

Enterprise Wireless LANs using 802.11 wireless protocol are too conservative in their spatial reuse. Recently, some works proposed taking advantage of scheduling packets by a single gateway. This work carries over the element of staggering transmissions from CAST.

Combining the capture and staggering aspects, we propose to schedule packets more efficiently and achieve optimal spatial reuse. A poster version of this work appeared in SIGCOMM CoNEXT 2007.

Capture Aware Staggered Transmissions (CAST) [pdf]

The 802.11 physical layer capture phenomenon was well studied. Its affects on the signal to noise ratio (SINR) required to capture a packet are very interesting and form the central part of this work. Different SINR thresholds are required based on the time of arrival of the signal and interference.

This work takes advantage of the difference in SINR requirements to stagger transmissions and increase spatial reuse. A distributed protocol is proposed which helps each node determine individually whether it can transmit concurrently. This work is accepted for IEEE WCNC 2008.

Routing with Opportunistically Coded eXchanges (ROCX) [pdf]

Network coding for wireless networks seems to fit very well with the broadcast nature of wireless networks. With the increasing interest in multi-hop mesh networks, the scope for network coding increases. In this work we explored the efficacy of routing packets to increase coding opportunities and improve end-to-end throughput.

The routing with coding for a given topology was formulated as a linear programming problem. This is a joint work with Bin Ni and appeared in the proceedings of IEEE WiMesh 2006.

Piggybacked-Ack aided Concurrent Transmissions (PACT) [pdf]

The 802.11 wireless protocol solves the hidden terminal problem but introduces the exposed terminal problem which reduces the spatial reuse. We proposed to use piggybacked-ACKs which are embedded in the RTS and CTS packets.

Each transmitter will receive an ACK for a previous packet in the CTS phase of the next transmission.The removal of ACKs reduces the number of role reversals. This enabled the modification of the protocol to allow exposed terminals to transmit concurrently. This work appeared in the poster session of IEEE ICNP 05.

Wireless Dual Athentication Protocol (WDAP) [pdf]

The Wireless Dual Authentication Protocol fixes the vulnerability arising due to a malicious access point. In this work we compared the standard RSN (802.11i) protocol from the security and latency angles. The testbed implementation with prism 2/2.5 chipset based wireless cards running hostap driver was used to measure the latencies. This was my master's thesis. This work was published at ISWCS 2005.