Edgar Costa Molero
PhD Student
I am a final-year year PhD student in the Networked Systems Group lead by Prof. Dr. Laurent Vanbever. My research focuses on the management and development of the next generation of networks using programable devices. In the past I worked on traffic engineering and anomaly detection in both legacy and SDN-based datacenter networks.
Before starting my PhD, I earned a bachelor’s degree in Information and Communication Technology from the Polytechnic University of Catalonia, Spain, and then a Master’s degree in Electrical Engineering and Information Technology from ETH Zürich.
Recent Publications
FAst In-Network GraY Failure Detection for ISPs
ACM SIGCOMM 2022. Amsterdam, Netherlands (August 2022).
Blink: Fast Connectivity Recovery Entirely in the Data Plane
USENIX NSDI 2019. Boston, Massachusetts, USA (February 2019).
We present Blink, a data-driven system that leverages TCP-induced signals to detect failures directly in the data plane. The key intuition behind Blink is that a TCP flow exhibits a predictable behavior upon disruption: retransmitting the same packet over and over, at epochs exponentially spaced in time. When compounded over multiple flows, this behavior creates a strong and characteristic failure signal. Blink efficiently analyzes TCP flows to: (i) select which ones to track; (ii) reliably and quickly detect major traffic disruptions; and (iii) recover connectivity---all this, completely in the data plane. We present an implementation of Blink in P4 together with an extensive evaluation on real and synthetic traffic traces. Our results indicate that Blink: (i) achieves sub-second rerouting for large fractions of Internet traffic; and (ii) prevents unnecessary traffic shifts even in the presence of noise. We further show the feasibility of Blink by running it on an actual Tofino switch.
Hardware-Accelerated Network Control Planes
ACM HotNets 2018. Redmond, WA, USA (November 2018).
One design principle of modern network architecture seems to be set in stone: a software-based control plane drives a hardware- or software-based data plane. We argue that it is time to revisit this principle after the advent of programmable switch ASICs which can run complex logic at line rate.
We explore the possibility and benefits of accelerating the control plane by offloading some of its tasks directly to the network hardware. We show that programmable data planes are indeed powerful enough to run key control plane tasks including: failure detection and notification, connectivity retrieval, and even policy-based routing protocols. We implement in P4 a prototype of such a “hardware-accelerated” control plane, and illustrate its benefits in a case study.
Despite such benefits, we acknowledge that offloading tasks to hardware is not a silver bullet. We discuss its tradeoffs and limitations, and outline future research directions towards hardware-software codesign of network control planes.
Lectures
Advanced Topics in Communication Networks
Autumn 2021
Advanced Topics in Communication Networks
Autumn 2020
Advanced Topics in Communication Networks
Autumn 2019
Communication Networks
Spring 2019
Advanced Topics in Communication Networks
Autumn 2018
Supervised Theses
Enhancing Data Plane Signals for Network Monitoring Systems (M)
21st century data visualization for enhancing student learning (B, S)
Gauging Risk in Resource Optimizations on Stateful Packet-Processing Devices (M)
Improving Current P4 Prototyping Tools (S)
