The Internet has led to the creation of a digital society, where (almost) everything is connected and is accessible from anywhere. However, despite their widespread adoption, traditional IP networks are complex and very hard to manage. It is both difficult to configure the network according to predefined policies, and to reconfigure it to respond to faults, load, and changes. To make matters even more difficult, current networks are also vertically integrated: the control and data planes are bundled together. Software-defined networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns, introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution. In this paper, we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound application programming interfaces (APIs), network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this new paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms—with a focus on aspects such as resiliency, scalability, performance, security, and dependability—as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment.

https://publications.uni.lu/bitstream/10993/20596/1/survey_on_SDN.pdf

Software-Defined Networking: A Comprehensive Survey

http://emamispnu.persiangig.com/Projects/Cloud%20Computing/science_2.pdf

Review: A survey on security issues in service delivery models of cloud computing

Software-Defined Networking (SDN) is an emerging paradigm that promises to change this state of affairs, by breaking vertical integration, separating the network's control logic from the underlying routers and switches, promoting (logical) centralization of network control, and introducing the ability to program the network. The separation of concerns introduced between the definition of network policies, their implementation in switching hardware, and the forwarding of traffic, is key to the desired flexibility: by breaking the network control problem into tractable pieces, SDN makes it easier to create and introduce new abstractions in networking, simplifying network management and facilitating network evolution. In this paper we present a comprehensive survey on SDN. We start by introducing the motivation for SDN, explain its main concepts and how it differs from traditional networking, its roots, and the standardization activities regarding this novel paradigm. Next, we present the key building blocks of an SDN infrastructure using a bottom-up, layered approach. We provide an in-depth analysis of the hardware infrastructure, southbound and northbound APIs, network virtualization layers, network operating systems (SDN controllers), network programming languages, and network applications. We also look at cross-layer problems such as debugging and troubleshooting. In an effort to anticipate the future evolution of this new paradigm, we discuss the main ongoing research efforts and challenges of SDN. In particular, we address the design of switches and control platforms -- with a focus on aspects such as resiliency, scalability, performance, security and dependability -- as well as new opportunities for carrier transport networks and cloud providers. Last but not least, we analyze the position of SDN as a key enabler of a software-defined environment.

The IoT paradigm holds the promise to revolutionize the way we live and work by means of a wealth of new services, based on seamless interactions between a large amount of heterogeneous devices. After decades of conceptual inception of the IoT, in recent years a large variety of communication technologies has gradually emerged, reflecting a large diversity of application domains and of communication requirements. Such heterogeneity and fragmentation of the connectivity landscape is currently hampering the full realization of the IoT vision, by posing several complex integration challenges. In this context, the advent of 5G cellular systems, with the availability of a connectivity technology, which is at once truly ubiquitous, reliable, scalable, and cost-efficient, is considered as a potentially key driver for the yet-to emerge global IoT. In the present paper, we analyze in detail the potential of 5G technologies for the IoT, by considering both the technological and standardization aspects. We review the present-day IoT connectivity landscape, as well as the main 5G enablers for the IoT. Last but not least, we illustrate the massive business shifts that a tight link between IoT and 5G may cause in the operator and vendors ecosystem.

/pdf/internet-of-things-in-the-5g-era-enablers-architecture-and-4vjccjwnie.pdf

Internet of Things in the 5G Era: Enablers, Architecture, and Business Models

There is currently considerable enthusiasm around the MapReduce (MR) paradigm for large-scale data analysis [17]. Although the basic control flow of this framework has existed in parallel SQL database management systems (DBMS) for over 20 years, some have called MR a dramatically new computing model [8, 17]. In this paper, we describe and compare both paradigms. Furthermore, we evaluate both kinds of systems in terms of performance and development complexity. To this end, we define a benchmark consisting of a collection of tasks that we have run on an open source version of MR as well as on two parallel DBMSs. For each task, we measure each system's performance for various degrees of parallelism on a cluster of 100 nodes. Our results reveal some interesting trade-offs. Although the process to load data into and tune the execution of parallel DBMSs took much longer than the MR system, the observed performance of these DBMSs was strikingly better. We speculate about the causes of the dramatic performance difference and consider implementation concepts that future systems should take from both kinds of architectures.

/pdf/a-comparison-of-approaches-to-large-scale-data-analysis-2ueig83wcw.pdf

A comparison of approaches to large-scale data analysis

"Every developer working with the Web needs to read this book." -- David Heinemeier Hansson, creator of the Rails framework "RESTful Web Services finally provides a practical roadmap for constructing services that embrace the Web, instead of trying to route around it." -- Adam Trachtenberg, PHP author and EBay Web Services Evangelist You've built web sites that can be used by humans. But can you also build web sites that are usable by machines? That's where the future lies, and that's what RESTful Web Services shows you how to do. The World Wide Web is the most popular distributed application in history, and Web services and mashups have turned it into a powerful distributed computing platform. But today's web service technologies have lost sight of the simplicity that made the Web successful. They don't work like the Web, and they're missing out on its advantages. This book puts the "Web" back into web services. It shows how you can connect to the programmable web with the technologies you already use every day. The key is REST, the architectural style that drives the Web. This book: Emphasizes the power of basic Web technologies -- the HTTP application protocol, the URI naming standard, and the XML markup languageIntroduces the Resource-Oriented Architecture (ROA), a common-sense set of rules for designing RESTful web servicesShows how a RESTful design is simpler, more versatile, and more scalable than a design based on Remote Procedure Calls (RPC)Includes real-world examples of RESTful web services, like Amazon's Simple Storage Service and the Atom Publishing ProtocolDiscusses web service clients for popular programming languagesShows how to implement RESTful services in three popular frameworks -- Ruby on Rails, Restlet (for Java), and Django (for Python)Focuses on practical issues: how to design and implement RESTful web services and clients This is the first book that applies the REST design philosophy to real web services. It sets down the best practices you need to make your design a success, and the techniques you need to turn your design into working code. You can harness the power of the Web for programmable applications: you just have to work with the Web instead of against it. This book shows you how.

RESTful Web Services

Rails just keeps on changing. Both Rails 3 and 4, as well as Ruby 1.9 and 2.0, bring hundreds of improvements, including new APIs and substantial performance enhancements. The fourth edition of this award-winning classic has been reorganized and refocused so it's more useful than ever before for developers new to Ruby and Rails. Rails 4 introduces a number of user-facing changes, and the ebook has been updated to match all the latest changes and new best practices in Rails. This includes full support for Ruby 2.0, controller concerns, Russian Doll caching, strong parameters, Turbolinks, new test and bin directory layouts, and much more. Ruby on Rails helps you produce high-quality, beautiful-looking web applications quickly. You concentrate on creating the application, and Rails takes care of the details. Tens of thousands of developers have used this award-winning book to learn Rails. It's a broad, far-reaching tutorial and reference that's recommended by the Rails core team. If you're new to Rails, you'll get step-by-step guidance. If you're an experienced developer, this book will give you the comprehensive, insider information you need. Rails has evolved over the years, and this book has evolved along with it. We still start with a step-by-step walkthrough of building a real application, and in-depth chapters look at the built-in Rails features. This edition now gives new Ruby and Rails users more information on the Ruby language and takes more time to explain key concepts throughout. Best practices on how to apply Rails continue to change, and this edition keeps up. Examples use Concerns, Russian Doll caching, and Turbolinks, and the book focuses throughout on the right way to use Rails. Additionally, this edition now works on Ruby 2.0, a new release of Ruby with substantial functional and performance improvements. This edition is for Rails4.0 and beyond.

/pdf/agile-web-development-with-rails-19puq3limf.pdf

Agile Web Development with Rails

The popularity of REST in recent years has led to tremendous growth in almost-RESTful APIs that dont include many of the architectures benefits. With this practical guide, youll learn what it takes to design usable REST APIs that evolve over time. By focusing on solutions that cross a variety of domains, this book shows you how to create powerful and secure applications, using the tools designed for the worlds most successful distributed computing system: the World Wide Web. Youll explore the concepts behind REST, learn different strategies for creating hypermedia-based APIs, and then put everything together with a step-by-step guide to designing a RESTful Web API.Examine API design strategies, including the collection pattern and pure hypermedia Understand how hypermedia ties representations together into a coherent API Discover how XMDP and ALPS profile formats can help you meet the Web API "semantic challenge" Learn close to two-dozen standardized hypermedia data formats Apply best practices for using HTTP in API implementations Create Web APIs with the JSON-LD standard and other the Linked Data approaches Understand the CoAP protocol for using REST in embedded systems

RESTful Web APIs

You want to write professional-grade applications: Rails is a full-stack, open-source web framework, with integrated support for unit, functional, and integration testing. It enforces good design principles, consistency of code across your team (and across your organization), and proper release management.But Rails is more than a set of best practices. Rails makes it both fun and easy to turn out very cool web applications. Need Ajax support, so your web applications are highly interactive? Rails has it built in. Want an application that sends and receives e-mail? Built in. Supports internationalization and localization? Built in. Do you need applications with a REST-based interface (so they can interact with other RESTful applications with almost no effort on your part)? All built-in.With this book, you'll learn how to use ActiveRecord to connect business objects and database tables. No more painful object-relational mapping. Just create your business objects and let Rails do the rest. Need to create and modify your schema? Migrations make it painless (and they're versioned, so you can roll changes backward and forward). You'll learn how to use the Action Pack framework to route incoming requests and render pages using easy-to-write templates and components. See how to exploit the Rails service frameworks to send emails, implement web services, and create dynamic, user-centric web-pages using built-in Javascript and Ajax support. There is extensive coverage of testing, and the rewritten Deployment chapter now covers Phusion Passenger.As with the previous editions of the book, we start with an extended tutorial that builds parts of an online store. And, of course, the application has been rewritten to show the best of Rails V2.

Sam Ruby

Papers

RESTful Web Services

Agile Web Development with Rails

RESTful Web APIs

Agile Web Development with Rails, Third Edition