An informal survey of real-world communications failures
PETER BAILIS, UC BERKELEY
KYLE KINGSBURY, JEPSEN NETWORKS
“The network is reliable” tops Peter Deutsch’s classic list, “Eight fallacies of distributed computing” (https://blogs.oracle.com/jag/resource/Fallacies.html), “all [of which] prove to be false in the long run and all [of which] cause big trouble and painful learning experiences.” Accounting for and understanding the implications of network behavior is key to designing robust distributed programs—in fact, six of Deutsch’s “fallacies” directly pertain to limitations on networked communications. This should be unsurprising: the ability (and often requirement) to communicate over a shared channel is a defining characteristic of distributed programs, and many of the key results in the field pertain to the possibility and impossibility of performing distributed computations under particular sets of network conditions.
> The Network is Reliable
Eventual Consistency Today: Limitations, Extensions, and Beyond
The Antifragile Organization
Decoupled from IP, TCP is at last able to support multihomed hosts.
CHRISTOPH PAASCH AND OLIVIER BONAVENTURE, UCL
The Internet relies heavily on two protocols. In the network layer, IP (Internet Protocol) provides an unreliable datagram service and ensures that any host can exchange packets with any other host. Since its creation in the 1970s, IP has seen the addition of several features, including multicast, IPsec (IP security), and QoS (quality of service). The latest revision, IPv6 (IP version 6), supports 16-byte addresses.
> Multipath TCP
Passively Measuring TCP Round-trip Times
You Don’t Know Jack about Network Performance
TCP Offload to the Rescue
An intellectual history of programmable networks
NICK FEAMSTER, GEORGIA INSTITUTE OF TECHNOLOGY
JENNIFER REXFORD, PRINCETON UNIVERSITY
ELLEN ZEGURA, GEORGIA INSTITUTE OF TECHNOLOGY
Designing and managing networks has become more innovative over the past few years with the aid of SDN (software-defined networking). This technology seems to have appeared suddenly, but it is actually part of a long history of trying to make computer networks more programmable.
> The Road to SDN
HTTP continues to evolve
HTTP (Hypertext Transfer Protocol) is one of the most widely used application protocols on the Internet. Since its publication, RFC 2616 (HTTP 1.1) has served as a foundation for the unprecedented growth of the Internet: billions of devices of all shapes and sizes, from desktop computers to the tiny Web devices in our pockets, speak HTTP every day to deliver news, video, and millions of other Web applications we have all come to depend on in our everyday lives.
> Making the Web Faster with HTTP 2.0
Improving Performance on the Internet
High Performance Web Sites
How Fast is Your Web Site?
A close look at RTT measurements with TCP
STEPHEN D. STROWES, BOUNDARY INC.
Measuring and monitoring network RTT (round-trip time) is important for multiple reasons: it allows network operators and end users to understand their network performance and help optimize their environment, and it helps businesses understand the responsiveness of their services to sections of their user base.
> Passively Measuring TCP Round-trip Times
You Don’t Know Jack about Network Performance
Bufferbloat: Dark Buffers in the Internet
TCP Offload to the Rescue
Cryptography as privacy works only if both ends work at it in good faith
The recent exposure of the dragnet-style surveillance of Internet traffic has provoked a number of responses that are variations of the general formula, “More encryption is the solution.” This is not the case. In fact, more encryption will probably only make the privacy crisis worse than it already is.
> More Encryption Is Not the Solution
Join us in Lombard, IL, April 3-5, 2013, for NSDI ’13.
The 10th USENIX Symposium on Networked Systems Design and Implementation (NSDI ’13) focuses on the design principles, implementation, and practical evaluation of large-scale networked and distributed systems. The technical sessions will focus on hot topics such as pervasive computing, network integrity, data centers, performance, big data, security, privacy, and many others. NSDI ’13 also includes a poster and demo session, where presenters can showcase early research and discuss it with fellow attendees.
Register by March 13 and save. Additional discounts are available!
Constraints in an environment empower the services.
PAT HELLAND, SALESFORCE.COM
Living in a condominium (commonly known as a condo) has its constraints and its services. By defining the lifestyle and limits on usage patterns, it is possible to pack many homes close together and to provide the residents with many conveniences. Condo living can offer a great value to those interested and willing to live within its constraints and enjoy the sharing of common services.
Similarly, in cloud computing, applications run on a shared infrastructure and can gain many benefits of flexibility and cost savings. To get the most out of this arrangement, a clear model is needed for the usage pattern and constraints to be imposed in order to empower sharing and concierge services. It is the clarity of the usage pattern that can empower new PaaS (Platform as a Service) offerings supporting the application pattern and providing services, easing the development and operations of applications complying with that pattern.
Just as there are many different ways of using buildings, there are many styles of application patterns. This article looks at a typical pattern of implementing a SaaS (Software as a Service) application and shows how, by constraining the application to this pattern, it is possible to provide many concierge services that ease the development of a cloud-based application.
Fighting Physics: A Tough Battle
Commentary: A Trip Without a Roadmap
CTO Roundtable: Cloud Computing
A proposal to improve the performance and availability of streaming video and other time-sensitive media
AIMAN ERBAD, QATAR UNIVERSITY; CHARLES “BUCK” KRASIC, GOOGLE
The Internet/Web architecture has developed to the point where it is common for the most popular sites to operate at a virtually unlimited scale, and many sites now cater to hundreds of millions of unique users. Performance and availability are generally essential to attract and sustain such user bases. As such, the network and server infrastructure plays a critical role in the fierce competition for users. Web pages should load in tens to a few hundred milliseconds at most. Similarly, sites strive to maintain multiple nines availability targets—for example, a site should be available to users 99.999 percent of the time over a one-year period.
Related content on queue.acm.org
Four Billion Little Brothers?: Privacy, mobile phones, and ubiquitous data collection
- Katie Shilton
VoIP: What is it Good for?
- Sudhir R. Ahuja, Robert En
Data in Flight
- Julian Hyde
An introduction to PTP and its significance to NTP practitioners
RICK RATZEL AND RODNEY GREENSTREET, NATIONAL INSTRUMENTS
It is difficult to overstate the importance of synchronized time to modern computer systems. Our lives today depend on the financial transactions, telecommunications, power generation and delivery, high-speed manufacturing, and discoveries in “big physics,” among many other things, that are driven by fast, powerful computing devices coordinated in time with each other.
Principles of Robust Timing over the Internet
The One-second War (What Time Will You Die?)
Modern Performance Monitoring