Which cloud computing characteristic enables consumers to provision new services with little to no interaction with humans at the provider?

Chapter 12—Unified Remote Access and BranchCache

One of the essential characteristics of cloud computing is broad network access. People need to be able to get the information they need from anywhere, and from any device. While this is often connected with the public cloud, the fact is that your users will need to access information in your private cloud, and they have the same expectations that they will be able to get to that information regardless of their current location, and regardless of type of device they are using. You will need to think about how you can provide secure remote access to your users. You will need to consider authentication and authorization, you will need to think about device state assessment, you will need to consider performance and reliability of connections, and what remote access methods work with what devices. In this chapter, we will go into the planning considerations you will need to make that will enable you to choose the right combination of Windows 8 technologies to enable the essential cloud characteristic of broad network access.

Summary

There are five key cloud characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service. A solution must exhibit these five characteristics to be considered a true cloud solution. There are four cloud deployment models: public, private, community, and hybrid. Each deployment model is defined according to where the infrastructure for the environment is located. There are three main cloud service models: Software as a Service, Platform as a Service, and Infrastructure as a Service. SaaS was the original cloud service model but the cloud has continued to grow and expand. Now a vast array of service models is available.

There are many factors pushing organizations toward the cloud, as well as many factors that are keeping organizations away. Each organization must evaluate cloud offerings for itself to see what best fits its needs.

Abstract

According to NIST definition of cloud computing, it has five characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service, while mobile computing focuses on device mobility and context awareness considering networking and mobile resource/data access. Mobile cloud computing is usually regarded as building on cloud computing and mobile computing; however, it has some unique features such as service offloading, migration, composition, etc. Mobile cloud computing enriches mobile computing technologies and leverages unified elastic resources of varied clouds and network technologies. This chapter provides an overview of various important concepts that are highly related to mobile cloud computing and illustrate their relations through real-world examples.

This chapter describes cloud computing technology and its impact on the data center network. We define the essential elements of cloud computing, including on-demand service, broad network access, resource pooling, elastic provisioning, and metered service at various quality of service levels. Models including software, platform, and infrastructure as a service (SaaS, PaaS, IaaS) are discussed, along with private, public, and hybrid cloud models and cloud service providers. Unique requirements of a cloud network include virtualization and virtual machine mobility, security, hypervisor virtual switching, converged storage, and new routing protocols such as Transparent Interconnection of Lots of Links (TRILL) and Shortest Path Bridging (SPB). We conclude with a brief discussion of software-defined networking (SDN) in the context of cloud computing.

What is the Cloud?

The term “cloud” has taken on a life of its own over the last several years. When talking about the cloud there are many different approaches that can be used.

When referring to the cloud the following are the essential characteristics that are needed for something to be referred to as a cloud service:

On-demand self-service.

Broad network access.

Resource pooling.

Rapid elasticity.

Measured service.

Some of the service models that are used to deploy the cloud are:

Software as a Service (SaaS).

Platform as a Service (PaaS).

Infrastructure as a Service (IaaS).

Within those service models the following are the deployment models that can be used:

Public/vendor cloud.

Private cloud and virtual private cloud.

On and off-premises.

Hybrid cloud.

Community cloud.

While cost is definitely one valuable reason for moving to the cloud the two big drivers typically focus around IT Efficiency and Business Agility:

IT Efficiency:

Enables a variable cost model for IT.

Minimizes overall IT costs—Shift CAPEX to OPEX.

Improves infrastructure resource deployment and utilization through virtualization.

Provides a flexible, reusable application development model.

Business Agility and Market Competitiveness:

Enables quicker “time-to-market.”

Rapid application deployment.

Reduced infrastructure setup/configuration.

Support for large-scale parallel programming.

Reduces switching costs associated with changing business strategies.

Alternatives for cost reduction efforts—allows for outsourcing segments of IT.

While this book is not about general cloud implementation, the focus is on the impact it has on security and overall APT.

One of the biggest reasons on why the cloud represents an exposure to many organizations is proper planning is not performed. If organizations actually understood the pros and cons, analyzed the exposures, and properly planned, the cloud can be an effective, cost-effective secure method for providing services to an organization.

1.1.1 Definitions

Before we discuss data in the cloud, we must first define what we mean both by the cloud and by data.

The National Institute of Standards and Technology (NIST) Special Publication 800-145 (NIST SP 800-145) defines the cloud as the hardware and software infrastructure required to provide “on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service.” These characteristics allow for three service models: software, platform, and infrastructure (Mell and Grance, 2011).

Software as a Service (SaaS) gives consumers use of software from providers that runs on cloud infrastructure. Examples of SaaS include social media like Facebook, Twitter, YouTube, and Pinterest. SaaS also includes email, website hosting, and data storage. Platform as a Service (PaaS) enables consumers to deploy and run their own software on the provider’s cloud infrastructure. Infrastructure as a Service (IaaS) means cloud providers host customer operating systems, so customers use their own software and control some network components (Mell and Grance, 2011).

NIST recognizes four deployment models for these service models: private, communal, public, or hybrid. Private clouds service a single individual, group, or organization. Communal clouds provide cloud services to a restricted community of consumers. Public clouds provide cloud services to the general public. Hybrid clouds have aspects of the other three, often to optimize these services (Mell and Grance, 2011).

By data we mean digital files like pictures, music, and documents; comments posted in tweets, blogs, and discussion threads. These things constitute data that you consciously place in cloud storage. However, your interaction with your cloud storage also provides or generates additional information, both about you and your data. This information could directly impact your privacy and security, or at a minimum it could leak or reveal important details about data that you thought private and secure. Cloud storage servers routinely collect this metadata, as do web browsers or applications that interact with cloud storage.

Cloud storage providers will collect metadata about your usage patterns, including network IP address, time, file size, file name, file action (add, modify, delete, etc.) to aid in quality of service (QoS).

Cloud data storage has many advantages for people, organizations, and companies. Cloud services give small businesses cost-effective access to capabilities that large companies often handle internally, thus bringing the benefits of scale economies to small businesses and making them more competitive. Cloud service providers also make these capabilities affordable to individuals too. Cloud services benefit people and companies by outsourcing hardware, software, maintenance, and management of data storage. Cloud storage provides off-site backup of critical data and allows access to the data anytime from anywhere. Cloud storage customers can easily increase their storage capacity too. Finally, studies have shown that outsourcing to the cloud can significantly cut company energy costs (Nedbal and Stieninger, 2014).

13.1 Introduction

When it comes to interconnectivity of devices and sharing of data through the Internet, the cloud computing paradigm is the go-to solution. The NIST definition of cloud computing contains five characteristics: on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service (Mell & Grance, 2011). With the emergence of the Internet of Things (IoT), where there is a need for interconnectivity between singular devices, the cloud paradigm has proved to be an effective solution till date. It provides reliable services based on virtual storage for the realization of IoT vision (Gubbi, Buyya, Marusic, & Palaniswami, 2013). However, with the recent boom in the IoT trend, increasing numbers of devices are being interconnected with the help of cloud computing. By 2020, it was expected that the number of interconnected devices would reach 24 billion (Gubbi et al., 2013) and by 2025 the total installed base of IoT-connected devices is projected to reach 75 billion according to Statista (Statista Research Department, 2016).

With this ever-increasing number of devices and the limited capacity of the cloud, it is natural that performance would decrease. To overcome the limitations, the fog computing paradigm was put forward. Unlike the centralized cloud, the fog computing model is highly distributed through its large number of fog nodes which provides localization. Therefore fog nodes are able to achieve low latency and context awareness (Bonomi, Milito, Zhu, & Addepalli, 2012). Fog computing and cloud computing are not mutually exclusive, rather they are implemented together to achieve the desired properties. The fog model contains an intermediate layer between cloud and user devices. This “fog layer” is closer to the end users, due to which a lower latency is achieved. The elements which make up this layer are called fog nodes. Any device that has computing capabilities, storage, and the ability to be connected with a network can act as a fog node (Fog Computing & the Internet of Things, 2016).

There are various features that make fog computing a nontrivial extension of cloud computing (Osanaiye et al., 2017), but for our model we are interested in two of these features: geographical distribution and location awareness. It is a well understood fact that device–server geographical distance and latency are correlated as the greater the distance, the more time that is taken by data packets to reach the destination. Therefore it is of great interest that fog computing servers are located in an optimum geographical position such that the greatest number of devices benefit from it. In this chapter, we propose a model for computing the geographical positions of fog nodes in a two-fog layer (F2C) network based on significant location points. Hence, the positions of the fog nodes are dependent on how the end-user devices are scattered in the region of concern.

After computing the positions, the two main applications of the F2C network are proposed. The first application is using the fog nodes as computational resources which provide computing services to the user devices and the second application is using the network as a physical layer for user-to-user data transmission.

Characteristics of a Cloud Infrastructure

The next topic we need to cover for cloud computing are the characteristics of a cloud infrastructure. The idea here is to expose the ways that cloud infrastructures differ from traditional computing environments.

On-demand self-service: The consumer can provision aspects of the service (CPU, storage, network, etc.) without the need to interact with the cloud provider. This is typically accomplished with the use of user interfaces and/or APIs.

Broad network access: It is critical that the cloud infrastructure be accessible via variety of network-capable devices, e.g. SmartPhones, PCs, laptops, tablets, and so on.

Resource pooling: The provider uses an infrastructure which allows for the pooling of physical computing resources to service many consumers. This implies a multi-tenant model. The most common technology used to accomplish this is a virtual machine(s). The advantage here is that it allows consumers who do not know or care about how their resources are being managed.

Rapid elasticity: This was already discussed. The basic idea is that resources can quickly be increased or decreased depending on the consumer’s needs. The manner in which this is accomplished is either manually or automatically.

Measured service: Cloud providers typically meter and measure the services they provide (CPU, memory, storage, etc.). The time unit or measurement is typically based on the hour. You only pay for what you use. Cloud logging providers typically charge based on the amount of log data you are allowed to send to the cloud, as well as how long you want to retain your log.

Multi-tenancy: Due to the multi-tenant nature of the cloud, there is a need “for policy-driven enforcement, segmentation, isolation, governance, service levels, and chargeback/billing models for different consumer constituencies” (Cloud Security Alliance, 2009).

More details on these topics can be found in Cloud Security Alliance (December 2009) and Web (2011a, 2011b).

Note

2.1 Cloud Computing Characteristics

The following are the five main characteristics of Cloud Computing that most people agree upon:

On-demand self-service: Cloud services are on-demand; that is, service consumers can automatically request the service based on their needs, without human interaction with the service provider.

Easy to access standardized mechanisms: NIST refers to this characteristic as broad network access; however, the term “global reach capability” is also used. The idea is that it should be possible to access cloud services through the network using standardized interfaces and access mechanisms. Having global reach capability does not mean that these services must always be accessible from the Internet, because this depends on the deployment model used. However, it should be possible to reach the service globally, when policies allow this.

Resource pooling and multi-tenancy: In Cloud Computing, resources [i.e., storages, processors, memory, network bandwidth, and virtual machines (VMs)] are shared between multiple tenants, and assigned exclusively at run time to one consumer at a time. Assigning resources is done dynamically based on the consumers’ needs. Sharing resources can help increase utilization, and hence significantly reduce the operation cost. Scheduling algorithms can be used to dynamically assign resources to different tenants based on the type of workload, fairness, locality, and many other factors [7,8].

Rapid elasticity: Elasticity is the ability to scale in and out by provisioning resources and releasing them, respectively. Cloud Computing should provide mechanisms to allow quick and automatic elasticity. The large pool of resources in cloud datacenters gives the illusion of infinite resources to the consumers, and elasticity provides the flexibility to provision these recourses on-demand.

Measured service: Providing cloud metrology or mechanisms to measure service usage as well as to monitor the health of services is crucial in Cloud Computing. Measuring services enables optimizing resources and provides transparency for both consumers and providers, allowing them to better utilize the service. Measured services can help in building closed-loop cloud systems that are fully automated.

Auditability and certifiability: Regulatory compliance requires enforcing rules and regulations. Services should provide logs and trails that allow the traceability of policies, so as to ensure that they are correctly enforced.

The list above (except point f) is based on the NIST definition. The list describes Cloud Computing based on what is currently available in the market, and represents the main characteristics of Cloud Computing in general. Many other characteristics can be added to this list in the future. For example, we added “auditability and certifiability” to the list above based on the current regulatory compliance requirements. On the other hand, comprehensive lists of characteristics can be made for each layer and each type of service provided in the cloud environment. For example, at the application level, a possible cloud service characteristic is that a service must be portable, pre-configured, or adaptable.