USENIX Update

Paper presented by Guohan Lu, Chuanxiong Guo, Yulong Li, Zhiqiang Zhou, Tong Yuan, Haitao Wu, Yongqiang Xiong, Rui Gao, and Yongguang Zhang of Microsoft Research Asia at the 8th USENIX Symposium on Networked Systems Design and Implementation (NSDI '11). Recipient of the Best Paper Award. Abstract: As one of the fundamental infrastructures for cloud computing, data center networks (DCN) have recently been studied extensively. We currently use pure software-based systems, FPGA based platforms, e.g., NetFPGA, or OpenFlow switches, to implement and evaluate various DCN designs including topology design, control plane and routing, and congestion control. However, software-based approaches suffer from high CPU overhead and processing latency; FPGA based platforms are difficult to program and incur high cost; and OpenFlow focuses on control plane functions at present. In this paper, we design a ServerSwitch to address the above problems. ServerSwitch is motivated by the observation that commodity Ethernet switching chips are becoming programmable and that the PCI-E interface provides high throughput and low latency between the server CPU and I/O subsystem. ServerSwitch uses a commodity switching chip for various customized packet forwarding, and leverages the server CPU for control and data plane packet processing, due to the low latency and high throughput between the switching chip and server CPU. We have built our ServerSwitch at low cost. Our experiments demonstrate that ServerSwitch is fully programmable and achieves high performance. Specifically, we have implemented various forwarding schemes including source routing in hardware. Our in-network caching experiment showed high throughput and flexible data processing. Our QCN (Quantized Congestion Notification) implementation further demonstrated that ServerSwitch can react to network congestions in 23us.

Paper presented by Damon Wischik, Costin Raiciu, Adam Greenhalgh, and Mark Handley of University College London at the 8th USENIX Symposium on Networked Systems Design and Implementation (NSDI '11). Recipient of the Best Paper Award. Abstract: Multipath TCP, as proposed by the IETF working group mptcp, allows a single data stream to be split across multiple paths. This has obvious benefits for reliability, and it can also lead to more efficient use of networked resources. We describe the design of a multipath congestion control algorithm, we implement it in Linux, and we evaluate it for multihomed servers, data centers and mobile clients. We show that some 'obvious' solutions for multipath congestion control can be harmful, but that our algorithm improves throughput and fairness compared to single-path TCP. Our algorithm is a drop-in replacement for TCP, and we believe it is safe to deploy.

Paper presented by Yong Wang of UESTC and Northwestern University; Daniel Burgener, Marcel Flores, and Aleksandar Kuzmanovic of Northwestern University; and Cheng Huang of Microsoft Research at the 8th USENIX Symposium on Networked Systems Design and Implementation (NSDI '11). Abstract: A highly accurate client-independent geolocation service stands to be an important goal for the Internet. Despite an extensive research effort and significant advances in this area, this goal has not yet been met. Motivated by the fact that the best results to date are achieved by utilizing additional 'hints' beyond inherently inaccurate delay-based measurements, we propose a novel geolocation method that fundamentally escalates the use of external information. In particular, many entities (e.g., businesses, universities, institutions) host their Web services locally and provide their actual geographical location on their Websites. We demonstrate that the information provided in this way, when combined with network measurements, represents a precious geolocation resource. Our methodology automatically extracts, verifies, utilizes, and opportunistically inflates such Web-based information to achieve high accuracy. Moreover, it overcomes many of the fundamental inaccuracies encountered in the use of absolute delay measurements. We demonstrate that our system can geolocate IP addresses 50 times more accurately than the best previous system, i.e., it achieves a median error distance of 690 meters on the corresponding data set.

The paper submissions deadline for the 7th USENIX Symposium on Networked Systems Design and Implementation (NSDI ’10) is approaching. Please submit your work by September 25, 2009.

NSDI focuses on the design principles and practical evaluation of large-scale networked and distributed systems. The goal is to bring together researchers from across the networking and systems community to foster a broad approach to addressing our common research challenges.

More information and submission guidelines can be found here.

USENIX NSDI ’10 will take place April 28–30, 2010, in  San Jose, CA.