Книга: Acing the CCNA Exam: Volume 1 Fundamentals and Protocols
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front matter

preface

In 2018, as a junior high school English teacher in the city of Kobe, Japan, I found myself at a crossroads. What I had originally intended to be a brief teaching stint in Japan had stretched into four years, and I was reaching the limit of my stay. I was in Japan on the Japan Exchange and Teaching (JET) Programme, a program sponsored by the Japanese government to bring recent university graduates to Japan to teach English for up to 5 years. As my tenure neared its end, I pondered my next step.

Being fascinated with computers since childhood, I found the field of IT a natural choice. I was no computer wizard—I had no experience in programming or anything of the sort—but after some searching, I stumbled upon the Cisco Certified Network Associate (CCNA) certification. If the stories were to be believed, getting CCNA certified was the gateway to a promising career in IT with a decent salary and plenty of room for growth. After a bit of studying, I was hooked! Peering under the hood of networks like the internet—an ubiquitous part of the modern world—was (and still is) endlessly fascinating.

Fast forward a year to 2019, and I was a network engineer at the world’s leading colocation data center and interconnection provider! I share my personal story here to emphasize that, with no formal education or previous experience on the topic, I was able to self-study, get certified, and make a 180-degree career change to enter the IT industry. And my story is no exception; I hear such stories from students all over the world on a daily basis.

You will occasionally encounter naysayers who downplay the value of the CCNA these days. One common argument is that, with the rise of cloud services like Amazon Web Services (AWS) and Microsoft Azure, there is less demand for network engineers; students should pursue cloud providers’ certifications instead. I couldn’t disagree more; connecting the complex multicloud infrastructure used by many modern enterprises is no simple task, and we need network professionals more than ever.

Studying a particular cloud service provider’s solutions before learning the fundamentals of networking is simply putting the cart before the horse—a house built on sand. The same can be said of pursuing the field of cybersecurity before grasping basics like networking. Network fundamentals are foundational knowledge for any IT professional, and the CCNA exam tests and certifies not only that you understand the fundamentals, but also that you have the skills to apply them in real networks. In our increasingly interconnected world, such knowledge and skills are invaluable—my story, and countless others’ stories, prove that.

This book—consisting of two volumes—is the culmination of insights gained from countless interactions with many thousands of students of my CCNA video course, refined and expanded to offer a comprehensive resource. For countless people—including myself—becoming CCNA certified has been truly life changing. There will be struggles and setbacks, but if you’re looking to make a change in your life and career, I can’t recommend the CCNA enough, and I hope that this book will inspire and empower you to pursue and achieve your CCNA certification.

acknowledgments

Writing and publishing a book is a major undertaking—certainly not something I could have done on my own! I’d like to thank everyone who contributed to this book in one way or another, directly or indirectly.

Thank you, to everyone at Manning who has worked hard on this book; there is a lot of behind-the-scenes work that goes into publishing a book. I’d like to thank my editor Connor O’Brien most of all for his valuable feedback on each chapter of this book. The book has turned out far better than it ever could have without his detailed reviews and guidance.

Thank you, Andy Waldron, acquisitions editor at Manning, for giving me a chance to write this book. I reached out to a few publishers about writing a CCNA book, and Andy was quick to respond and express his interest. After a few quick calls, the contract was signed, and the rest is history!

Thank you, Jeremy Cioara, for your contributions as technical editor for the book. Jeremy Cioara is an author, educator, and business owner known for his ability to simplify complex technical concepts into entertaining and practical explanations. He brings more than two decades of experience, a love of learning, and a keen eye for detail.

Thank you, all of the reviewers, for your time and valuable feedback at each stage of the process: Amit Lamba, Andrea Cosentino, Casey Burnett, Eder Andrés Ávila Niño, Emmanuele Piccinelli, Emilio Grande, Gavin Smith, George Gyftogiannis, Glen Thompson, Greg MacLean, Jeremy Chen, John Bisgrove, John Guthrie, Jose Apablaza, Narayanan Seshan, Nghia To, Paul Love, Pedro Seromenho, Raghunath Mysore, Simone Sguazza, Sushil Singh, Vladislav Bilay, and Zachary Manning. Special thanks go to Munish Kaushal, my technical proofreader, for your careful reviews of the many (very many!) figures, commands, and examples in this book.

I’d also like to thank everyone who has supported Jeremy’s IT Lab during the past five years. It’s because of all of you that I can pursue my dream as a job—for that, I am forever grateful. Writing a CCNA book would never have crossed my mind without your support. Special thanks go to those on the Jeremy’s IT Lab Discord server for being a totally awesome and supportive group, always willing to lend a hand and lift each other up (without forgetting to have fun).

Finally, thank you, my friends and family who have supported me in my personal life during this process; writing a book is a major time commitment and often means neglecting the more important parts of life. Thank you, Miki, for your understanding and constant encouragement during my long work hours throughout the whole process, and thanks, Mom and Dad, for your support and encouragement as always.

about this book

Acing the CCNA Exam was written with one goal in mind: to help you prepare for and successfully pass the CCNA exam. It begins from zero and assumes no previous knowledge, covering network fundamentals and every CCNA exam topic step by step.

Who should read this book

As an exam study guide, this book is for anyone who wants to pass the CCNA exam and attain their CCNA certification. If that’s you (good choice, by the way), you’ve come to the right place! Even for those who already have their CCNA or are already working in the field, this book will be a useful resource for reference, covering key network protocols and how to configure them on Cisco routers and switches.

How this book is organized

The CCNA exam is quite wide in scope, and as a result, this book is divided into two volumes. This is volume 1, consisting of 24 chapters arranged across 6 parts:

Part 1 lays the foundation of networking concepts, introducing how networks operate at a basic level, the devices that form a network, and the protocols that govern communication:

Part 2 delves into how data navigates through complex networks, focusing on routing principles, the end-to-end journey of a data packet, and segmenting a network with subnetting:

Part 3 focuses on technologies and protocols used by switches to facilitate their role in forwarding frames in an efficient, reliable, and secure manner:

Part 4 covers key protocols used by routers—dynamic routing protocols to enable automatic and adaptive packet forwarding, and first-hop redundancy protocols to provide a reliable gateway for hosts in a LAN:

Part 5 introduces the next generation of the Internet Protocol, IPv6, designed to overcome the limitations of IPv4 and support the internet of the future:

Part 6 explores the role of the Layer 4 protocols TCP and UDP, as well as how to use IP access controls lists (ACLs) for filtering and securing network traffic:

Additionally, there are four appendixes, each of which should prove helpful in your exam preparation:

If you are just beginning your CCNA studies, I highly recommend starting from volume 1 (this volume) and reading the chapters in order; each chapter builds upon the previous ones, assuming familiarity with all preceding material. However, if you are using this book as a secondary resource (having already completed another course of study, such as my video series), feel free to treat the book more as a reference guide. In this case, you can directly consult chapters that address specific areas you want to focus on. Appendix A will be particularly useful for this targeted study, as it lists which chapters in which volume address each CCNA exam topic.

About Cisco CLI commands and output formatting

This book contains many examples of Cisco command-line interface (CLI) commands and output in examples and in line with normal text. These examples are formatted in a fixed-width font like this to separate it from ordinary text, using the syntax conventions shown in the following table. Code annotations accompany many of the code examples and highlight important concepts. Where necessary, the code has been reformatted to accommodate the available page space, and where code wraps, we've used line-continuation markers (➥).

Table 1 CLI syntax conventions

Convention

Description

Standard text

Command prompts and CLI output not typed by the user.

Bold text

Commands and keywords as typed by the user.

Italic text

Arguments in a command for which you supply values.

[x]

Square brackets indicate optional elements, such as optional keywords.

. . .

An ellipsis indicates that output has been abbreviated/omitted.

|

Pipes (vertical bars) are used to separate mutually exclusive elements, as shown in the following two conventions (square brackets and curly braces).

[x | y]

Optional alternative elements are enclosed in square brackets and separated by pipes.

{x | y}

Mandatory alternative elements are enclosed in curly braces and separated by pipes.

Each command in this book will be explained as it is introduced, but you can refer to this table as needed for clarification. The following examples demonstrate some of these different syntax conventions:

liveBook discussion forum

Purchase of Acing the CCNA Exam includes free access to liveBook, Manning’s online reading platform. Using liveBook’s exclusive discussion features, you can attach comments to the book globally or to specific sections or paragraphs. It’s a snap to make notes for yourself, ask and answer technical questions, and receive help from the author and other users. . You can also learn more about Manning’s forums and the rules of conduct at .

Manning’s commitment to our readers is to provide a venue where a meaningful dialogue between individual readers and between readers and the author can take place. It is not a commitment to any specific amount of participation on the part of the author, whose contribution to the forum remains voluntary (and unpaid). We suggest you try asking him some challenging questions lest his interest stray! The forum and the archives of previous discussions will be accessible from the publisher’s website as long as the book is in print.

Other online resources

There is no shortage of helpful resources for CCNA students online. I have collected some of my recommended resources (video courses, practice exams, etc.) on my website at .

Another page that every CCNA candidate should have bookmarked is the official exam topics list at . This is where you can find what Cisco expects you to know to pass the CCNA exam.

Finally, I recommend bookmarking Cisco Certification Roadmaps at . This page will give you information about Cisco’s yearly certification review process. If there are any scheduled changes coming to the CCNA exam, they will be listed on this page well in advance.

about the author

Jeremy McDowell is a senior network engineer from Canada, living and working in Japan for over 10 years. After graduating with a bachelor of music degree from the University of Toronto, he taught English in Japan for five years before entering the networking industry in 2019.

Combining his knowledge of networking with his teaching skills, Jeremy has helped thousands of students study for and pass the CCNA exam through his YouTube channel Jeremy’s IT Lab, which currently has over 340,000 subscribers.

about the cover illustration

The figure on the cover of Acing the CCNA Exam, titled “Maître d’école,” or “Teacher,” is taken from a book by Louis Curmer published in 1841. Each illustration is finely drawn and colored by hand.

In those days, it was easy to identify where people lived and what their trade or station in life was just by their dress. Manning celebrates the inventiveness and initiative of the computer business with book covers based on the rich diversity of regional culture centuries ago, brought back to life by pictures from collections such as this one.

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