Stephen Stuart
Stephen is a Distinguished Engineer at Google. His current focus area is developing secure, reliable, scalable software-defined networking (SDN) solutions for enterprise applications. Past efforts at Google include building teams and solutions in SDN for datacenters and WAN, network architecture, and network management software. Prior to Google, he was VP of Engineering for both Switch & Data and MFN, CTO for MIBH, and a Consulting Engineer at Digital Equipment Corporation.
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Google has been developing solutions for enterprise networking using SDN, including contributing to the open-source FAUCET project. This talk discusses how the FAUCET approach enables security, development velocity, and other innovation.
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Since the publication of OpenFlow: Enabling Innovation in Campus Networks in 2008, there has been a lot of published work and experience with SDN and OpenFlow in large networks and in datacenters, including at Google. In this article we will discuss an open source SDN controller, FAUCET. FAUCET was created to bring the benefits of SDN to a typical enterprise network and has been deployed in various settings, including the Open Networking Foundation, which runs an instance of FAUCET as their office network. FAUCET delivers high forwarding performance using switch hardware, while enabling operators to add features to their networks and deploy them quickly, in many cases without needing to change (or even reboot) hardware - and interoperates with neighboring non-SDN network devices.
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BwE: Flexible, Hierarchical Bandwidth Allocation for WAN Distributed Computing
Sushant Jain
Nikhil Kasinadhuni
Enrique Cauich Zermeno
C. Stephen Gunn
Jing Ai
Björn Carlin
Mathieu Robin
Amin Vahdat
Sigcomm '15, Google Inc (2015)
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WAN bandwidth remains a constrained resource that is economically infeasible to substantially overprovision. Hence, it is important to allocate capacity according to service priority and based on the incremental value of additional allocation. For example, it may be the highest priority for one service to receive 10Gb/s of bandwidth but upon reaching such an allocation, incremental priority may drop sharply favoring allocation to other services. Motivated by the observation that individual flows with fixed priority may not be the ideal basis for bandwidth allocation, we present the design and implementation of Bandwidth Enforcer (BwE), a global, hierarchical bandwidth allocation infrastructure. BwE supports: i) service-level bandwidth allocation following prioritized bandwidth functions where a service can represent an arbitrary collection of flows, ii) independent allocation and delegation policies according to user-defined hierarchy, all accounting for a global view of bandwidth and failure conditions, iii) multi-path forwarding common in traffic-engineered networks, and iv) a central administrative point to override (perhaps faulty) policy during exceptional conditions. BwE has delivered more service-efficient bandwidth utilization and simpler management in production for multiple years.
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BwE: Flexible, Hierarchical Bandwidth Allocation for WAN Distributed Computing
Björn Carlin
C. Stephen Gunn
Enrique Cauich Zermeno
Jing Ai
Mathieu Robin
Nikhil Kasinadhuni
Sushant Jain
ACM SIGCOMM 2015 (to appear)
Preview abstract
WAN bandwidth remains a constrained resource that is economically infeasible to substantially overprovision. Hence,it is important to allocate capacity according to service priority and based on the incremental value of additional allocation in particular bandwidth regions. For example, it may be highest priority for one service to receive 10Gb/s of bandwidth but upon reaching such an allocation, incremental priority may drop sharply favoring allocation to other services. Motivated by the observation that individual flows with fixed priority may not be the ideal basis for bandwidth allocation, we present the design and implementation of Bandwidth Enforcer (BwE), a global, hierarchical bandwidth allocation infrastructure. BwE supports: i) service-level bandwidth allocation following prioritized bandwidth functions where a service can represent an arbitrary collection of ows, ii) independent allocation and delegation policies according to user-defined hierarchy, all accounting for a global view of bandwidth and failure conditions, iii) multi-path forwarding common in traffic-engineered networks, and iv) a central administrative point to override (perhaps faulty) policy during exceptional conditions. BwE has delivered more service-efficient bandwidth utilization and simpler management in production for multiple years.
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Jupiter Rising: A Decade of Clos Topologies and Centralized Control in Google’s Datacenter Network
Joon Ong
Amit Agarwal
Glen Anderson
Ashby Armistead
Roy Bannon
Seb Boving
Gaurav Desai
Paulie Germano
Jeff Provost
Jason Simmons
Eiichi Tanda
Jim Wanderer
Amin Vahdat
Sigcomm '15, Google Inc (2015)
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We present our approach for overcoming the cost, operational complexity, and limited scale endemic to datacenter networks a decade ago. Three themes unify the five generations of datacenter networks detailed in this paper. First, multi-stage Clos topologies built from commodity switch silicon can support cost-effective deployment of building-scale networks. Second, much of the general, but complex, decentralized network routing and management protocols supporting arbitrary deployment scenarios were overkill for single-operator, pre-planned datacenter networks. We built a centralized control mechanism based on a global configuration pushed to all datacenter switches. Third, modular hardware design coupled with simple, robust software allowed our design to also support inter-cluster and wide-area networks. Our datacenter networks run at dozens of sites across the planet, scaling in capacity by 100x over ten years to more than 1Pbps of bisection bandwidth.
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B4: Experience with a Globally Deployed Software Defined WAN
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Sushant Jain
Joon Ong
Subbaiah Venkata
Jim Wanderer
Junlan Zhou
Min Zhu
Amin Vahdat
Proceedings of the ACM SIGCOMM Conference, Hong Kong, China (2013)
