Crane: Fast and Migratable GPU Passthrough for OpenCL applications

Wednesday May 17th, 12-1PM @ BA5205

Speaker: James Gleeson

Title:
Crane: Fast and Migratable GPU Passthrough for OpenCL applications

Abstract:
General purpose GPU (GPGPU) computing in virtualized environments leverages PCI passthrough to achieve GPU performance comparable to bare-metal execution. However, GPU passthrough prevents service administrators from performing virtual machine migration between physical hosts.
Crane is a new technique for virtualizing OpenCL-based GPGPU computing that achieves within 5.25% of passthrough GPU performance while supporting VM migration. Crane interposes a virtualization-aware OpenCL library that makes it possible to reclaim and subsequently reassign physical GPUs to a VM without terminating the guest or its applications. Crane also enables continued GPU operation while the VM is undergoing live migration by transparently switching between GPU passthrough operation and API remoting.
 

Bio:
James is a PhD student under Eyal de Lara.  He has done research in mobile security for both physical and software attacks on Android phones.  His current research interests are in heterogeneous computing in data centers.

The Game of Twenty Questions: Do You Know Where to Log?

Thursday May 4th, 12-1PM @ BA5205

Speaker: Xu Zhao

Title:
The Game of Twenty Questions: Do You Know Where to Log?

Abstract:
A production system’s printed logs are often the only source of runtime information available for postmortem debugging, performance profiling, security auditing, and user behavior analytics.  Therefore, the quality of this data is critically important. Recent work has attempted to enhance log quality by recording additional variable values, but logging statement placement, i.e., where to place a logging statement, which is the most challenging and fundamental problem for improving log quality, has not been adequately addressed so far. This position paper proposes an automated placement of logging statements by measuring the uncertainty of software that can be eliminated. Guided by ideas from information theory, authors describe a simple approach that automates logging statement placement. Preliminary results suggest that the algorithm can effectively cover, and further improve, existing logging statements placed by developers. It can compute an optimal log-placement that disambiguates the entire function call path with only 0.218% of
slowdown.

Bio:
Xu Zhao is a 2nd year PhD student at the University of Toronto, under the supervision of Prof. Ding Yuan. His research interests lie in the area of performance of distributed systems and failure diagnosis. His current work focuses on automated placement of logging statements and non-intrusive performance profiling for distributed systems.

Challenges and Solutions to Secure Internet Geolocation

Wednesday May 3rd , 12-1PM @ BA5205

Speaker: AbdlRahman Abdou

Title:
Challenges and Solutions to Secure Internet Geolocation

Abstract:
The number of security-sensitive location-aware services over the Internet continues to grow, such as location-aware authentication, location-aware access policies, fraud prevention, complying with media licensing, and regulating online gambling/voting. 
An adversary can evade existing geolocation techniques, e.g., by faking GPS coordinates or employing a non-local IP address through proxy and virtual private networks. In this talk, I will present parts of my PhD work, including Client Presence Verification (CPV), which is a measurement-based technique designed to verify an assertion about a device’s presence inside a prescribed geographic region. CPV does not identify devices by their IP addresses. Rather, the device’s location is corroborated in a novel way by leveraging geometric properties of triangles, which prevents an adversary from manipulating network delays to its favor. To achieve high accuracy, CPV mitigates Internet path asymmetry using a novel method to deduce one-way application-layer delays to/from the client’s participating device, and mines these delays for evidence supporting/refuting the asserted location. I will present CPV’s evaluation results, including the granularity of the verified location and the verification time, and summarize some lessons we learned throughout the process.

Bio:
AbdelRahman Abdou is a Post-Doctoral Fellow in the School of Computer Science at Carleton University. He received his PhD (2015) in Systems and Computer Engineering from Carleton University. His research interests include location-aware security, SDN security, authentication, SSL/TLS and using Internet measurements to solve problems related to Internet security.