The Updated Version of the Bestselling Nessus Book.
This is the ONLY Book to Read if You Run Nessus Across the Enterprise
Ever since its beginnings in early 1998, the Nessus Project has attracted security researchers from all walks of life. It continues this growth today. It has been adopted as a de facto standard by the security industry, vendor, and practitioner alike, many of whom rely on Nessus as the foundation to their security practices. Now, a team of leading developers have created the definitive book for the Nessus community.
* Perform a Vulnerability Assessment
Use Nessus to find programming errors that allow intruders to gain unauthorized access.
* Obtain and Install Nessus
Install from source or binary, set up up clients and user accounts, and update your plug-ins.
* Modify the Preferences Tab
Specify the options for Nmap and other complex, configurable components of Nessus.
* Understand Scanner Logic and Determine Actual Risk
Plan your scanning strategy and learn what variables can be changed.
* Prioritize Vulnerabilities
Prioritize and manage critical vulnerabilities, information leaks, and denial of service errors.
* Deal with False Positives
Learn the different types of false positives and the differences between intrusive and nonintrusive tests.
* Get Under the Hood of Nessus
Understand the architecture and design of Nessus and master the Nessus Attack Scripting Language (NASL).
* Scan the Entire Enterprise Network
Plan for enterprise deployment by gauging network bandwith and topology issues.
* Nessus is the premier Open Source vulnerability assessment tool, and has been voted the "most popular" Open Source security tool several times.
* The first edition is still the only book available on the product.
* Written by the world's premier Nessus developers and featuring a foreword by the creator of Nessus, Renaud Deraison.

This exam is designed to validate Windows Server 2003 Microsoft Certified Systems Administrators (MCSEs) AD, Network Infrastructure, and Application Platform Technical Specialists skills. The object of this exam is to validate only the skills that are are different from the existing MCSE skills. This exam will fulfill the Windows Server 2008 Technology Specialist requirements of Exams 70-640, 70-642, and 70-643.
The Microsoft Certified Technology Specialist (MCTS) on Windows Server 2008 credential is intended for information technology (IT) professionals who work in the complex computing environment of medium to large companies. The MCTS candidate should have at least one year of experience implementing and administering a network operating system in an environment that has the following characteristics: 250 to 5,000 or more users; three or more physical locations; and three or more domain controllers.
MCTS candidates will manage network services and resources such as messaging, a database, file and print, a proxy server, a firewall, the Internet, an intranet, remote access, and client computer management.
In addition MCTS candidates must understant connectivity requirements such as connecting branch offices and individual users in remote locations to the corporate network and connecting corporate networks to the Internet.
* THE independent source of exam day tips, techniques, and warnings not available from Microsoft
* Comprehensive study guide guarantees 100% coverage of all Microsoft's exam objectives
* Interactive FastTrack e-learning modules help simplify difficult exam topics
* Two full-function ExamDay practice exams guarantee double coverage of all exam objectives
* Free download of audio FastTracks for use with iPods or other MP3 players
* 1000 page "DRILL DOWN" reference for comprehensive topic review

Uncertain data is inherent in many important applications, such as environmental surveillance, market analysis, and quantitative economics research. Due to the importance of those applications and rapidly increasing amounts of uncertain data collected and accumulated, analyzing large collections of uncertain data has become an important task. Ranking queries (also known as top-k queries) are often natural and useful in analyzing uncertain data.

"Ranking Queries on Uncertain Data" discusses the motivations/applications, challenging problems, the fundamental principles, and the evaluation algorithms of ranking queries on uncertain data. Theoretical and algorithmic results of ranking queries on uncertain data are presented in the last section of this book. "Ranking Queries on Uncertain Data" is the first book to systematically discuss the problem of ranking queries on uncertain data.

This volume explains how advances in computer technology will augment communication in person-to-person, organizational, and educational settings. It describes the convergence of virtual reality and group decision support, and how these will serve educational and organizational effectiveness. Contributors--experts from business and academia--examine what the computing/communications world will look like in the near future, what the specific needs of various industries will be, and how innovations will fit into organizations and society.

These three topics are addressed with attention to the following questions: What will be the size of initial and future markets for advanced computer and communications technology? What will be the future computing environment in manufacturing operations, in the executive suite, in the office, in the field and on the road, at the point of service, for the computer-integrated enterprise, at home, in the school, and in the global marketplace?

Peer-to-Peer (P2P) networks enable users to directly share digital content (such as audio, video, and text files) as well as real-time data (such as telephony traffic) with other users without depending on a central server. Although originally popularized by unlicensed online music services such as Napster, P2P networking has recently emerged as a viable multimillion dollar business model for the distribution of academic and clinical information, telecommunications, and social networking. Written at an accessible level for any reader familiar with fundamental Internet protocols, Peer-to-Peer Networking and Applications explains the conceptual operations and architecture underlying basic P2P systems using well-known commercial systems as models. The book also delineates the latest research directions, thereby providing not only a sophisticated understanding of current systems, but also the means to improve upon these systems with innovations that will better performance, security, and flexibility. Peer-to-Peer Networking and Applications is thus both a valuable starting point and an important reference to those practioners employed by any of the 200 companies with approximately $400 million invested in this new and lucrative technology.
* Uses well-known commercial P2P systems as models, thus demonstrating real-world applicability.
* Discusses how current research trends in wireless networking, high-def content, DRM, etc. will intersect with P2P, allowing readers to account for future developments in their designs.
* Provides online access to the Overlay Weaver P2P emulator, an open source tool that supports a number of peer-to-peer applications with which readers can practice.

This book includes a number of selected papers from the PRO-VE '07 Conference, providing a comprehensive overview of recent advances in various Collaborative Networks domains. It covers trust aspects, performance and value systems, VO breeding environments, VO creation, e-contracting, collaborative architectures and frameworks, professional virtual communities, interoperability issues, business benefits, and case studies and applications in industry and services.

The term Quality of Service, abbreviated QoS, refers to network resource control mechanisms. Quality of Service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. This book brings all of the elements of network quality of service (QoS) together in a single volume, saving the reader the time and expense of making multiple purchases. It introduces network QoS, explains the basics, describes the protocols, and discusses advanced topics, by the best and brightest experts in the field. It is a quick and efficient way to bring valuable content together from leading experts in the field while creating a one-stop-shopping opportunity for customers to receive the information they would otherwise need to round up from separate sources.
* Chapters contributed by recognized experts cover theory and practice of network quality of service (QoS), allowing the reader to develop a new level of knowledge and technical expertise.
* Presents methods of analysis and problem-solving techniques, enhancing the reader's grasp of the material and ability to implement practical solutions.
* Use of examples illustrate core QoS concepts for enhanced comprehension

Service-Oriented Infrastructures including Grid and Cloud Computing are technologies in a critical transition to wider adoption by business. Their use may enable enterprises to achieve optimal IT utilization, including sharing resources and services across enterprises and on-demand utilization of those made available by business partners over the network. This book is an essential reference for researchers and practitioners in service-oriented IT. It analyses a selection of common capabilities (services capturing reusable functionality of IT solutions) that have been applied to tackle challenging business problems and were validated by the BEinGRID consortium in real-life business trials covering most European market sectors.

This exam is designed to validate Windows Server 2003 Microsoft Certified Systems Administrators (MCSAs) AD and Application Platform Technical Specialists skills. The object of this exam is to validate only the skills that are are different from the existing MCSA skills. This exam will fulfill the Windows Server 2008 Technology Specialist requirements of Exams 70-640 and 70-643.
The Microsoft Certified Technology Specialist (MCTS) on Windows Server 2008 credential is intended for information technology (IT) professionals who work in the complex computing environment of medium to large companies. The MCTS candidate should have at least one year of experience implementing and administering a network operating system in an environment that has the following characteristics: 250 to 5,000 or more users; three or more physical locations; and three or more domain controllers.
MCTS candidates will manage network services and resources such as messaging, a database, file and print, a proxy server, a firewall, the Internet, an intranet, remote access, and client computer management.
In addition MCTS candidates must understant connectivity requirements such as connecting branch offices and individual users in remote locations to the corporate network and connecting corporate networks to the Internet.

* THE independent source of exam day tips, techniques, and warnings not available from Microsoft
* Comprehensive study guide guarantees 100% coverage of all Microsoft's exam objectives
* Interactive FastTrack e-learning modules help simplify difficult exam topics
* Two full-function ExamDay practice exams guarantee double coverage of all exam objectives
* Free download of audio FastTracks for use with iPods or other MP3 players
* 1000 page "DRILL DOWN" reference for comprehensive topic review

Network management refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems, which includes controlling, planning, allocating, deploying, coordinating, and monitoring the resources of a network. This book brings all of the elements of network management together in a single volume, saving the reader the time and expense of making multiple purchases. It introduces network management, explains the basics, describes the protocols, and discusses advanced topics, by the best and brightest experts in the field. It is a quick and efficient way to bring valuable content together from leading experts in the field while creating a one-stop-shopping opportunity for customers to receive the information they would otherwise need to round up from separate sources.
* Chapters contributed by recognized experts in the field cover theory and practice of network management, allowing the reader to develop a new level of knowledge and technical expertise.
* This book's up-to-date coverage of network quality of service issues facilitates learning and lets the reader remain current and fully informed from multiple viewpoints.
* Presents methods of analysis and problem-solving techniques, enhancing the reader's grasp of the material and ability to implement practical solutions.
* Use of examples illustrate core network management concepts for enhanced comprehension.

Innovation in Manufacturing Networks A fundamental concept of the emergent business, scientific and technological paradigms ces area, innovation the ability to apply new ideas to products, processes, organizational practices and business models - is crucial for the future competitiveness of organizations in a continually increasingly globalised, knowledge-intensive marketplace. Responsiveness, agility as well as the high performance of manufacturing systems is responsible for the recent changes in addition to the call for new approaches to achieve cost-effective responsiveness at all the levels of an enterprise. Moreover, creating appropriate frameworks for exploring the most effective synergies between human potential and automated systems represents an enormous challenge in terms of processes characterization, modelling, and the development of adequate support tools. The implementation and use of Automation Systems requires an ever increasing knowledge of enabling technologies and Business Practices. Moreover, the digital and networked world will surely trigger new business practices. In this context and in order to achieve the desired effective and efficiency performance levels, it is crucial to maintain a balance between both the technical aspects and the human and social aspects when developing and applying new innovations and innovative enabling technologies. BASYS conferences have been developed and organized so as to promote the development of balanced automation systems in an attempt to address the majority of the current open issues.

This book focuses on broadband distribution and systems architecture and concentrates on practical concepts that will allow the reader to do their own design, improvement, and troubleshooting work. The objective is to enhance the skill sets of a large population that designs and builds broadband cable plants, as well as those maintaining and troubleshooting it. A large cross-section of technical personnel who need to learn these skills design, maintain, and service HFC systems from signal creation through transmission to reception and processing at the customer end point. In addition, data/voice and video specialists need to master and reference the basics of HFC design and distribution before contending with the intricacies of their own unique services. This book serves as an essential reference to all cable engineers-those who specifically design and maintain the HFC distribution plant as well as those primarily concerned with data/voice technology as well as video technology. Included is an online component consisting of spreadsheets that were used in developing the material presented in the book.
* Concentrates on practical concepts that will allow the user to do his own design, improvement, and trouble-shooting work.
* Prepares cable engineers and technicians to work with assurance as they face the latest developments and future directions.
* Concise and tightly focused, allowing readers to easily find answers to questions about an idea or concept they are developing in this area.

Focused on renewable energy systems and the development of information and communication technologies (ICTs) for their integration in smart grids, this book presents recent advances and methods that help to ensure that power generation from renewable sources remains stable, that power losses are minimized, and that the reliable functioning of these power generation units is maintained. The book highlights key topics and technologies for renewable energy systems including the intelligent control of power generators, power electronics that connect renewable power generation units to the grid, and fault diagnosis for power generators and power electronics. In particular, the following topics are addressed: * Modeling and control of power generators (PMSGs, DFIGs); * Modeling and control of power electronics (converters, inverters); * Modeling and fault diagnosis of the transmission and distribution Grid; and * Modelling and control of distributed power generation units (interconnected synchronous generators or photovoltaic units). Because of the above coverage, members of the wider engineering community will find that the nonlinear control and estimation methods presented provide essential insights into the functioning of renewable energy power systems, while the academic community will find the book a valuable textbook for undergraduate or graduate courses on renewable energy systems.

This book provides a comprehensive examination of Internet QoS theory, standards, vendor implementation and network deployment from the practitioner's point of view, including extensive discussion of related economic and regulatory issues. Written in a technology-light way so that a variety of professionals and researchers in the information and networking industries can easily grasp the material. Includes case studies based on real-world experiences from industry.
The author starts by discussing the economic, regulatory and technical challenges of the existing QoS model. Key coverage includes defining a clear business model for selling and buying QoS in relation to current and future direction of government regulation and QoS interoperability (or lack thereof) between carriers and networking devices. The author then demonstrates how to improve the current QoS model to create a clear selling point, less regulation uncertainty, and higher chance of deployment success. This includes discussion of QoS re-packaging to end-users; economic and regulatory benefits of the re-packaging; and the overall benefits of an improved technical approach. Finally, the author discusses the future evolution of QoS from an Internet philosophy perspective and lets the reader draw the conclusions.
This book is the first QoS book to provide in depth coverage on the commercial and regulatory aspects of QoS, in addition to the technical aspect. From that, readers can grasp the commercial and regulatory issues of QoS and their implications on the overall QoS business model. This book is also the first QoS book to provide case studies of real world QoS deployments, contributed by the people who did the actual deployments. From that, readers can grasp the practical issues of QoS in real world. This book is also the first QoS book to cover both wireline QoS and wireless QoS. Readers can grasp the QoS issues in the wireless world. The book was reviewed and endorsed by a long list of prominent industrial and academic figures.
* The only book to discuss QoS technology in relation to economic and regulatory issues
* Includes case studies based on real-world examples from industry practitioners.
* Provides unique insight into how to improve the current QoS model to create a clear selling point, less regulatory uncertainty, and higher chance of deployment success.

Network processors are the basic building blocks of today's high-speed, high-demand, quality-oriented communication networks. Designing and implementing network processors requires a new programming paradigm and an in-depth understanding of network processing requirements. This book leads the reader through the requirements and the underlying theory of networks, network processing, and network processors. It covers implementation of network processors and intergrates EZchip Microcode Development Environment so that you can gain hands-on experience in writing high-speed networking applications. By the end of the book, the reader will be able to write and test applications on a simulated network processor.
Comprehensive, theoretical, and pracitical coverage of networks and high-speed networking applicationsDescirbes contemporary core, metro, and access networks and their processing algorithmsCovers network processor architectures and programming models, enabling readers to assess the optimal network processor typer and configuration for their applicationFree download from http: //www.cse.bgu.ac.il/npbook includes microcode development tools that provide hands-on experience with programming a network processor

Strengthen your understanding of fast-moving WDMA optical network technology, and learn how to better select and design reliable all-optical telecom networks with this practical book. It will help expand your knowledge of LLN, Manhattan, Shuffle, De Bruijn, Gemmet, Matrix, Swift, and Starnet and will show you how to employ an effective method of network organization based on traffic demands.

Sleep medicine has been developing for more than 40 years. The current concepts in sleep technology are mainly centered on polysomnography (PSG) and issues related to sleep technicians. However, the editorsbelieve that the true value of technology is revealed only when benefits to humanity are manifest. To this end, they endeavor to create a new era in sleep technology, one that will improve the quality of people's sleep and daily lives.

This edited book, Introduction to Modern Sleep Technology, provides a comprehensive reference volume to the latest advancements in the area of Sleep Technology. It offers an excellent range of insights and opinions from leading researchers and experts in multiple disciplines spanning academia, clinical practice and industry. Up-to-date insights into the current research topics in this field are featured in addition to the latest technological advances with reference to appropriate working examples.

Thecurrentbookcombines the five dimensions of knowledge, i.e., sleep medicine, clinical psychology engineering, industrial design and technology management to ensure the content is applicable to people's daily lives.

This edited book, Introduction to Modern Sleep Technology, provides a comprehensive reference volume to the latest advancements in the area of Sleep Technology. It offers an excellent range of insights and opinions from leading researchers and experts in multiple disciplines spanning academia, clinical practice and industry. Up-to-date insights into the current research topics in this field are featured in addition to the latest technological advances with reference to appropriate working examples.

Thecurrentbookcombines the five dimensions of knowledge, i.e., sleep medicine, clinical psychology engineering, industrial design and technology management to ensure the content is applicable to people's daily lives.

Thecurrentbookcombines the five dimensions of knowledge, i.e., sleep medicine, clinical psychology engineering, industrial design and technology management to ensure the content is applicable to people's daily lives.

Exchange 2007 represents the biggest advance in the history of Microsoft Exchange Server technology. Given Exchange's leap to x64 architecture and its wide array of new features, it isn't surprising that the SP1 release of 2007 would be particularly robust in terms of hotfixes, security enhancements and additional functionality.
Tony Redmond's upgraded edition of his popular Microsoft Exchange Server 2007 bible features extensive coverage of the significant changes and additions offered with SP1. Every chapter has been updated, with particular focus on the most pivotal aspects of SP1, including:
*install enabling on Windows Server 2008
*IVp6 support
*Unified Messaging inclusion
*EMC enhancements
*Client Access Improvements for Outlook Web Access and Activesync
*New user interfaces for POP3 and IMAP4
*System resource monitoring and message routing improvements
*New features for the mailbox server role
*.pst file data managment improvements
*new high-availability features
*optimization for mobile access
*and much more
*Complete coverage of all the updates in SP1 ensure admins skip the initial 2007 release's bugs and upgrade with ease
*Written by HP Services CTO Tony Redmond, the world's most trusted author of Exchange books for over a decade
*250+ pages of updates throughout, including totally new sections on Windows 2008 compatibility, Microsoft Yona, Windows Mobile 6 and 6.1 devices, Apple iPhone, and more

The future for Nagios in the enterprise is certainly bright! "Nagios 3 Enterprise Network Monitoring" can help you harness the full power of Nagios in your organization. Nagios 3 contains many significant new features and updates, and this book details them all for you. Once up and running, you'll see how a number of useful add-ons and enhancements for Nagios can extend the functionality of Nagios throughout your organization. And, if you want to learn how to write your own plugins...this is the book for you! In these pages you'll find a cookbook-style chapter full of useful plugins that monitor a variety of devices, from HTTP-based applications to CPU utilization to LDAP servers and more.
* Complete Case Study Demonstrates how to Deploy Nagios Globally in an Enterprise Network
* Monitor Third Party Hardware Devices with Nagios

SHORT DESCRIPTION:
Multiprotocol Label Switching (MPLS) is a data plane and control technology that is used in packet (that is Internet Protocol) networks. Now over ten years old, it has taken root firmly as a fundamental tool in many service provider networks. The last ten years have seen a considerable consolidation of MPLS techniques and protocols. This has resulted in the abandoning of some of the original features of MPLS, and the development of other new features. MPLS has moved from a prospective solution, to a grown-up technology. Now that MPLS has reached this level of maturity, these new tools and features allow more sophisticated services to the users of the network. These tools and features are discussed within various contexts throughout several networking-related books published by MK and this presents us with a unique publishing opportunity.
The proposed book is a best-of-the-best collection of existing content from several books MK has published in recent years on MPLS technology (multi-label protocol switching). Individual chapters on MPLS technology are derived from a handful of MK books and are combined in one new volume in a way that makes sense as a reference work for those interested in new and developing aspects of this technology, i.e., network operators and designers who need to determine which aspects of their networks would benefit from MPLS technology and applications. It also serves as a definitive reference for engineers implementing MPLS-based products.
This book represents a quick and efficient way to bring valuable content together from leading experts in the field while creating a one-stop-shopping opportunity for customers to receive the information they would otherwise need to round up from separate sources. Suitable and current content will be collected from the following titles: Evans, Deploying IP and MPLS QoS (2006); Farrel, GMPLS (2005); Ash, Traffic Engineering (2006); Vasseur, Network Recovery (2005); Farrel, The Internet and Its Protocols (2004); Nadeau, MPLS Management (2003); and Davie, MPLS Technology and Applications (2000). These chapters will be updated where necessary and two new chapters will be added at the beginning and the end of the book to bring the content into focus and discuss next generation developments.

* Coverage of major applications of MPLS such as traffic engineering, VPNs, IP integration, GMPLS, and QoS written by leading experts in the field contributes to your practical knowledge of this key technology
* Shows you how to implement various MPLS applications that will result in saving your organization time and money
* Shows you how you can evaluate MPLS applications and techniques in relation to one another so you can develop an optimum network design

Over the past decade, the world has witnessed an explosion in the development and deployment of new wireless network technologies. From cellular mobile telephony to the ubiquitous "WiFi" networks in coffee-shops and airports, to the emerging WiMAX wireless broadband access networks, the menu of wireless access systems has become so comprehensive that wireline access to user devices may soon become a relic of the past. Wireless Networking serves as a one-stop view of cellular, WiFi, and WiMAX networks, as well as the emerging wireless ad hoc and sensor networks. Rather than provide descriptive accounts of these technologies and standards, the book emphasizes conceptual perspectives on the modeling, analysis, design and optimization of such networks. Furthermore, the authors present wireless networking within the unifying framework of resource allocation, using simple abstractions of the underlying physical wireless communication. In short, Wireless Networking is an in-depth, exhaustive, and invaluable asset to anyone working in this rapidly evolving field.
*Goes beyond descriptive and qualitative treatments, by presenting the foundations underlying the various wireless networking technologies
*Provides abstractions, models and analyses of established and emerging wireless networks, thereby supplying the reader with a conceptual and quantitative treatment, thus ensuring longevity of the learning from this material
*Aids comprehension by including over 120 figures, four appendices on the mathematics of the various models, several inline exercises, and extensive problem sets at the end of each chapter

Business and IT organizations are currently embracing new strategically sound concepts in order to be more customer-centric, competitive, and cognitive in their daily operations. While useful, the various software tools, pioneering technologies, as well as their unique contributions largely go unused due to the lack of information provided on their special characteristics. Novel Practices and Trends in Grid and Cloud Computing is a collection of innovative research on the key concerns of cloud computing and how they are being addressed, as well as the various technologies and tools empowering cloud theory to be participative, penetrative, pervasive, and persuasive. While highlighting topics including cyber security, smart technology, and artificial intelligence, this book is ideally designed for students, researchers, and business managers on the lookout for innovative IT solutions for all the business automation software and improvisations of computational technologies.

"Digital Design: An Embedded Systems Approach Using VHDL" provides a foundation in digital design for students in computer engineering, electrical engineering and computer science courses. It takes an up-to-date and modern approach of presenting digital logic design as an activity in a larger systems design context.
Rather than focus on aspects of digital design that have little relevance in a realistic design context, this book concentrates on modern and evolving knowledge and design skills. Hardware description language (HDL)-based design and verification is emphasized--VHDL examples are used extensively throughout. By treating digital logic as part of embedded systems design, this book provides an understanding of the hardware needed in the analysis and design of systems comprising both hardware and software components.
Includes a Web site with links to vendor tools, labs and tutorials.
Presents digital logic design as an activity in a larger systems design context.
Features extensive use of VHDL examples to demonstrate HDL (hardware description language) usage at the abstract behavioural level and register transfer level, as well as for low-level verification and verification environments.
Includes worked examples throughout to enhance the reader's understanding and retention of the material.
Companion Web site includes links to tools for FPGA design from Synplicity, Mentor Graphics, and Xilinx, VHDL source code for all the examples in the book, lecture slides, laboratory projects, and solutions to exercises."

This volume contains the proceedings of the Seventh Mediterranean Ad Hoc Networking Workshop (Med-Hoc-Net'2008), celebrated in Palma de Mallorca (llles Balears, Spain) during June 25-27, 2008. This IFIP TC6 Workshop was organized by the Universitat de les Illes Balears in cooperation with the Asociaci6n de Tdcnicos de lnform tica and sponsored by the following Working Groups: WG6.3 (Performance of Computer Networks) and WG6.8 (Mobile and Wireless Communications). The rapid evolution of the networking industry introduces new exciting challenges that need to be explored by the research community. Aside the adoption of Internet as the global network infrastructure these last years have shown the growing of a set of new network architectures without a rigid and known a priori architecture using wireless techniques, like sensor and ad-hoc networks. These new types of networks are opening the possibility to create a large number of new applications ranging from domestic to nature surveying. These new networks are generating new technical challenges like the capability of auto-reconfiguration in order to give the network an optimal configuration, the energy saving need when the nodes have not a source of energy other than a small battery, new protocols to access the network and to convey the information across the network when its structure is not completely known or should be discovered, new paradigms for keeping the needed information security and privacy in a quite uncontrolled environment, and others.