Free CCNA | Network Devices | Day 1 | CCNA 200-301 Complete Course

Summary

هذا النص يحتوي على مقدمة لدورة CCNA من IT Lab بقلم Jeremy، تهدف الدورة إلى تغطية جميع موضوعات الامتحان الرسمي لـ CCNA بطريقة مفتوحة ومجانية. الدورة تتضمن مقاطع فيديو تغطية جميع الموضوعات، واختبارات تمرين وبطاقات تذكيرية ومختبرات تعليمية باستخدام بُطاقتر. الدورة مناسبة لأي شخص يرغب في النجاح في الامتحان CCNA 200-301، وتشمل معلومات قيمة عن الشبكات الكمبيوترية للجميع، بغض النظر عن الهدف النهائي. المتطلبات الوحيدة هي معرفة أساسية بالحواسيب، مع تغطية المعرفة الأساسية للشبكات في بداية الدورة.

Takeaways

• 📚 هذا الدورة تستهدف ال取证 Cisco Certified Network Associate (CCNA) مع المحتوى الكامل ل次会议通过 الامتحان، مفتوح المصدر 100%.
• 🎓 الدورة تغطي المحاضرات التعليمية، الاختبارات التدريبية، البطاقات التذكارية، المختبرات التدريبية باستخدام بلاك تراسير، واختبارات ممارسة لتحضير المرشحين للامتحان الحقيقي.
• 🌐 الدورة مبنية على قائمة موضوعات الامتحان الرسمي لـ Cisco، مع معلومات إضافية لتحسين فهم الشبكات بشكل عام.
• 👥 الدورة مناسبة لأي شخص يريد取证 CCNA 200-301، وتشمل معلومات قيمة عن الشبكات الكمبيوتر حتى لو لم يهدف الشخص إلى取证 CCNA.
• 💻 لا حاجة إلى معرفة مسبقة في الشبكات أو البرمجة، حيث سيغطي الدورة المعرفة الأساسية في البداية.
• 🔌 الشبكات تسمح للعقداء (Nodes) بالمشاركة في الموارد، وtypes of network nodes مثل الروتين (Router) والسويتش (Switch) وال방화벽 (Firewall) والخادم (Server) والعميل (Client).
• 🔄 العميل هو جهاز يستخدم خدمة مقدمة بواسطة الخادم، في حين أن الخادم هو جهاز يوفر وظائف أو خدمات للعملاء.
• 🌟 يمكن أن يكون同一个设备 في بعض المواقف عميلًا وفي أماكن أخرى خادمًا، بحسب الوظيفة التي يقوم بها في الشبكة.
• 🛡️ السويتش يوفر اتصالًا لأجهزة LAN، في حين أن الروتين يوفر اتصالًا بين LANs وعبر الإنترنت.
• 🔒 ال방화벽 هو جهاز أمان متخصص يتحكم في المرور الشبكي الداخلي والخارجي للشبكة، ويتطلب تكوين قواعد الأمان لتحديد المرور الذي يجب السماح به أو رفضه.
• 📈 الدورة تقدم مواد تدريبية تعزيز المعرفة واختبارات ممارسة ومختبرات تعليمية، مع القدرة على استخدام بلاك تراسير لممارسة الشبكات الافتراضية.

Q & A

ما هي الهدف من الدورة التدريبية CCNA التي يقدمها Jeremy؟

الدورة التدريبية تهدف لتكون دورة كاملة لـ CCNA، تتضمن كل ما تحتاجه لعبور الامتحان، وتكون مفتوحة مجانًا.

ما هي المتطلبات الأساسية لانضمام الدورة التدريبية CCNA؟

المتطلبات الأساسية هي مجرد معرفة أساسية بالحواسيب، وأنه لا تحتاج إلى معرفة شبكات أو برمجيات قبل البدء في الدورة التدريبية.

ما هي الأنواع المختلفة من الأجهزة الشبكاتية التي تغطيها الدورة التدريبية؟

تغطي الدورة التدريب أجهزة مختلفة مثل الروتين (router)، التحويل (switch)، الجدار الأماني (firewall)، الخادم (server)، والعميل (client).

ما هي الوظيفة الأساسية للجهاز الروتين في الشبكات؟

الوظيفة الأساسية للجهاز الروتين هي تزويدي الشبكات لنقل البيانات بين الشبكات المحلية (LANs) وعبر الإنترنت.

كيف يساعد التحويل (switch) في الشبكات؟

التحويل يوفر اتصالًا لأجهزة النهاية مثل الحواسيب داخل الشبكة المحلية (LAN) وينقل البيانات بينها.

ما هي الوظيفة الرئيسية للجدار الأماني (firewall) في الشبكة؟

الجدار الأماني يتحكم في المرور الشبكي الذي يدخل ويخرج من الشبكة، ويحمي الأجهزة الطرفية مثل الحواسيب والخوادم.

كيف يحدد العميل والخادم في الشبكات؟

العميل هو جهاز يستخدم خدمة مقدمة بواسطة الخادم، بينما الخادم هو جهاز يوفر وظائف أو خدمات للعملاء.

ما هي الوظيفة الأساسية للخادم في الشبكة؟

الخادم هو جهاز يوفر وظائف أو خدمات للعملاء، مثل الخدمة السحابية أو تخزين البيانات.

ما هي الميزة الرئيسية للجدار الأماني الجيل التالي (next-generation firewall)؟

الجدار الأماني الجيل التالي يجمع ميزات الجدار الأماني التقليدي مع ميزات تصفية متقدمة مثل نظام منع ال渗透 (IPS).

ما هي المصادر الثلاثة الأساسية للدورة التدريبية CCNA؟

المصادر الأساسية هي الأسئلة ال随堂 (quizzes) التي تظهر بعد كل فيديو، بطاقات المراجعة (flashcards) التي يمكن استخدامها مع برنامج 'Anki'، ومختبرات التدريب باستخدام برنامج 'Packet Tracer'.

Outlines

00:00

📚 CCNA课程介绍与网络基础

Jeremy的IT实验室推出的CCNA（Cisco Certified Network Associate）课程旨在提供全面的内容，帮助学生通过考试，且完全免费。课程内容包括讲座视频、实践测验、学习卡片、模拟实验室以及模拟考试。课程基于Cisco官方考试大纲，但也提供额外信息以增强对网络的一般理解。课程适合希望参加CCNA 200-301考试的人士，即使没有网络知识背景，也只需具备基本的计算机熟悉度。课程从网络设备基础知识开始，逐步深入。

05:02

🔌 网络节点及其功能

本段介绍了网络中的不同节点类型，包括路由器、交换机、防火墙、服务器和客户端，并解释了它们在网络中的作用。通过构建一个简单的网络示例，说明了节点如何共享资源和通信。客户端被定义为访问服务器提供服务的设备，而服务器则是提供功能或服务给客户端的设备。同一设备在不同情况下可以是客户端或服务器。

10:03

🌐 企业网络构建与连接

这一段进一步扩展了网络构建的概念，展示了如何通过交换机将多个终端设备连接到局域网（LAN）中。解释了交换机的作用和特点，以及它们如何促进LAN内设备间的通信。同时，介绍了路由器在连接不同LAN以及通过互联网发送数据中的关键角色。通过一个企业网络的例子，说明了纽约和东京分支机构之间的数据传输是如何通过路由器和互联网进行的。

15:07

🛡️ 防火墙在网络安全中的作用

本段讨论了网络安全的重要性，并介绍了防火墙的功能和特点。防火墙作为网络安全设备，控制进出网络的流量。根据配置的安全规则，防火墙可以决定哪些流量被允许或拒绝。介绍了Cisco的两款防火墙：ASA5500-X系列和Firepower 2100系列，并解释了它们作为下一代防火墙的先进功能。同时，也提到了基于主机的防火墙作为额外的防御层的重要性。

20:07

📚 网络定义与节点类型复习

这一段对网络的定义和各种网络节点类型进行了复习，并强调了网络设备的种类繁多，课程将在后面覆盖更多类型。预告了本讲座的补充材料，包括视频末尾的测验、使用Anki软件的预制学习卡片，以及Cisco的网络模拟软件Packet Tracer的实践实验室。这些资源旨在帮助学生练习和提高对材料的理解。

25:11

📝 视频测验与CCNA考试准备

本段提供了一个视频测验，包括几个选择题，旨在帮助学生以类似于Cisco考试的方式进行自我测试。问题涉及网络硬件的购买、AirDrop交易中的角色、观看视频时设备的功能，以及公司网络升级的决策。每个问题都有详细的答案分析，以确保学生能够理解每个选项的正确与错误。

30:13

🙌 结束语与支持呼吁

视频的最后部分是结束语，呼吁观众通过订阅频道、点赞视频、留言和分享视频来表达支持。同时，提到了通过Patreon或加密货币捐赠来支持频道的选项，并在视频描述中提供了链接。

Keywords

💡CCNA

CCNA، Cisco Certified Network Associate، هي شهادة ت증ين مهارات الشبكات وتتضمن دروس شاملة تغطي جميع المفاهيم الأساسية للشبكات. في النص، يُستخدم CCNA لوصف الدورة التدريبية التي تستهدف النجاح في الامتحان الرسمي للشهادة.

💡_exam topics list

قائمة موضوعات الامتحان هي قائمة محددة من قبل Cisco تتضمن جميع المفاهيم التي يجب تغطيتها في الدورة التدريبية CCNA. في النص، يُذكر أنها تغطي كل موضوع في قائمة CCNA الرسمي.

💡lecture videos

مقاطع المحاضرات هي أجزاء من الدورة التعليمية التي تشرح موضوعات معينة بتفصيل. في النص، يُذكر أن الدورة تتضمن مقاطع فيديو تغطي كل موضوع في CCNA.

💡practice quizzes

الاختبارات التجريبية هي جزء من التدريب الذي يساعد الطلبة على التحقق من معرفتهم وتحسينها. في النص، تُذكر الاختبارات التجريبية كجزء من الدورة لمراجعة المواد الدراسية.

💡flashcards

بطاقات المراجعة هي أداة تعليمية تستخدم لمساعدتهم في التذكر والمراجعة. في النص، يُذكر بطاقتها كأداة لمساعدتهم على تذكر ما تعلموه في الدورة.

💡Packet Tracer

Packet Tracer هو برنامج تقليدي يستخدم لتدريب الشبكات وتجربةها. في النص، يُستخدم(Packet Tracer) لممارسة المختبرات التعليمية.

💡network simulation

المحاكاة الشبكية هي عملية استخدام برامج كمبيوترية لتجربة وتصميم الشبكات. في النص، يُستخدم لتدريب الطلبة على استخدام Packet Tracer لتجربة الشبكات.

💡router

الروتر هو جهاز شبكي يستخدم لتوصيل الشبكات وتوجيه المرور بينها. في النص، يُشرح الروتر ووظيفة توجيه البيانات بين الشبكات.

💡switch

المبدل هو جهاز شبكي يستخدم لتوصيل الأجهزة في نفس الشبكة المحلية. في النص، يُشرح المبدل ووظيفة توجيه البيانات داخل الشبكة المحلية.

💡firewall

الجدار النار هو جهاز شبكي يستخدم لحماية الشبكة من الهجمات الإلكترونية. في النص، يُشرح الجدار النار ووظيفة حماية الشبكة.

💡server

الخادم هو جهاز شبكي يوفر خدمات أو وظائف لأجهزة العميل. في النص، يُشرح الخادم ووظيفة توفير الخدمات للأجهزة التابعة للشبكة.

💡client

العميل هو جهاز يستخدم لطلب خدمات من الخادم. في النص، يُشرح العميل ووظيفة الوصول إلى الخدمات التي تقدمها الخادم.

💡LAN (Local Area Network)

LAN هي شبكة محلية ت容許 الأجهزة في نفس المكان المجاور تتواصل مع بعضها البعض. في النص، يُستخدم LAN لوصف الشبكة المحلية التي تربط الأجهزة في نفس المكان.

Highlights

Introduction to the complete CCNA course by Jeremy’s IT Lab, offering a free comprehensive guide to pass the CCNA exam.

Course content includes lecture videos, practice quizzes, flashcards, practice labs with Packet Tracer, and practice exams.

The course is designed for anyone aiming to pass the CCNA 200-301 exam, set to release on February 24th, 2020.

No prior networking knowledge is required, as foundational networking concepts will be covered from the start.

The course will also provide extra information to improve general understanding of networks beyond exam topics.

Explanation of network devices as the foundation of network knowledge, starting with an overview of a sample network.

Definition of a network as per Wikipedia, emphasizing the sharing of resources among network nodes.

Introduction to different types of network nodes including routers, switches, firewalls, servers, and clients.

Detailed explanation of the function of a router in a network and its role in connecting different networks.

Clarification of the switch's role in forwarding traffic within a Local Area Network (LAN).

Firewalls are introduced as network security devices that control incoming and outgoing traffic based on rules.

Servers are defined as devices providing services or functions for clients, with examples of different types of servers.

Clients are explained as devices accessing services provided by servers, with various examples of client devices.

Illustration of client-server relationships in different scenarios, such as file sharing and video streaming.

Discussion on the placement and function of firewalls in a network to protect against external attacks.

Differentiation between host-based and network firewalls, and the importance of both for network security.

Overview of Cisco's enterprise-grade switches and routers, and their characteristics in network architecture.

Supplementary materials provided for the course, including end-of-video quizzes, flashcards, and practice labs with Packet Tracer.

Quizzes at the end of the video to test understanding of network devices, their functions, and network concepts.

Transcripts

Welcome to my complete CCNA, Cisco Certified Network Associate course. This is Jeremy’s

IT Lab. Since this is the first video, allow me to introduce the course. This course aims

to be a complete course for the CCNA, including everything you need to pass the exam, all

100% free. There will be lecture videos covering every

topic on Cisco’s official exam topics list, practice quizzes covering the material in

each lecture, flashcards to help you review and remember what you learned, practice labs

using Cisco’s network simulation software Packet Tracer, and at the end multiple practice

exams to get you ready for the real thing. Although this course will be based on Cisco’s

official exam topics list, I also want to give you extra information to improve your

understanding of networks in general. That additional context should also help you understand

the exam topics.

Because this is the first video in the series, I want to talk about who this course is for.

This course is for anyone who wants to pass the CCNA 200-301 exam. At the time of recording

this video, this is a new exam that isn’t released yet, but will be coming on February

24th, 2020. Although a lot of the information will overlap with the old CCNA, the course

will be based on the exam topics for the 200-301 exam

This course is for anyone who wants to learn about computer networking. You don’t necessarily

have to take the CCNA 200-301 exam, this course will cover lots of valuable information regarding

computer networking even if you’re not aiming for the CCNA.

The only requirement for this course is that you have a basic familiarity with computers.

I will cover all of the foundational networking knowledge at the beginning of the course,

so you don’t need any prior knowledge of networking, and you also don’t need to know

programming or anything like that to start this course.

With no further ado, let’s get started! Our first lesson will cover network devices.

This knowledge will be the foundation which we will build upon during the rest of this

course. Take a look at this sample network here. Do you know what each of these symbols

represents, and their function in a network? At the end of this lesson, you’ll know these

and more, and how they work together to make a network. We won’t go into too many details

in this lesson. There’s plenty of time to dig deeper in future lessons, but these first

few videos are meant to give you the foundational knowledge which we will build upon in future

lessons.

So, what is a network? Let’s ask our friends at Wikipedia. ‘a computer network is a digital

communications network which allows nodes to share resources’. Well, if you didn’t

understand before, you probably still don’t after reading just that. Let’s look further.

The definition states that a network allows nodes to share resources. What is a node?

I’ll introduce some types of network nodes here, some of which appeared in the sample

network on the previous slide.

This is a router. You’ve probably heard the word before and have a general idea of

what a router is. But I’ll explain a router’s function in this lesson.

Next, this is a switch. Maybe you’re familiar with what a switch is, maybe not. It serves

a different function than a router, but is also similar in many ways.

This next one is a firewall. You’re probably familiar with firewalls, and you most likely

have a firewall installed on your computer. That’s a software firewall, but large networks

usually have a hardware firewall, a separate network appliance, which helps protect the

network.

This next symbol represents a server. If you know computers, you surely have heard of servers

before. What exactly do they do? Well, if you’re watching this video, you’re getting

it from a server on the Internet.

The last symbol in this slide is a client. You’re using a client to watch this video,

whether it’s a smart phone, a laptop, a desktop PC, or whatever. What exactly is a

client? Let’s get into it. Over the next few slides let’s build a sample network

and look at the functions of each of these network nodes in the network.

You might also hear clients, as well as the previous node type, servers, referred to as

end hosts or endpoints

Okay, so we looked at some types of network nodes, but we didn’t really examine exactly

what each type of node does in a network. Let’s build a network and examine each node’s

role.

So, here we have two PCs. PC1 on the left, and PC2 on the right. As is, this isn’t

a network. However, if I connect them together with a cable…

We now have a network. That’s right, two PCs connected together actually makes a network!

Now, it’s a very simple network, but if we take a look at that Wikipedia definition

once more…

‘A computer network is a digital telecommunications network which allows nodes to share resources’

Now that these two nodes are connected, they can share resources...

And essentially have a conversation with each other.

Now, I’m representing clients with this symbol. But there are all kinds of devices

which can be network clients.

For example, a laptop or

Desktop PC running Microsoft Windows. Or how about an iMAC running macOS. Or even an apple

iphone running iOS. These are just a few examples of devices which can be network clients.

So, let’s give a simple definition of a client.

A client is a device that accesses a service made available by a server.

Okay, since server is part of the definition of a client, to understand one, you have to

understand the other.

So, what’s a server? Let’s take a look.

I used this symbol to represent a server. When you think of the word server, you may

thing of something like this IBM server, or this DELL server. And indeed, these are powerful

servers, and you’ll see rows and rows of servers like these in data centers. However,

not all servers look like this. In fact, any of the clients we looked at in the previous

slide can be servers too! How is that possible? Well, let’s look at the definition of a

client again, and then compare it to the definition of a server.

The definition we used for a client was ‘a client is a device that accesses a service

made available by a server.’ So, we can basically reverse that definition to know

what a server is.

‘A server is a device that provides functions or services for clients.’ So, let’s look

at the simple network of two PCs connected with a cable that we saw before.

Remember this network? Watch this little exchange between the two PCs and think which of them

is the server and which is the client.

PC1 asks PC2 for the file ‘image.jpg’

PC2 responds and sends the requested image file. So, which is the client and which is

the server? Well, PC1 is the one requesting the service, requesting for the image to be

sent. And PC2 is the one providing the service, the one sending the image. So that makes PC1

the client, and PC2 the server.

Let’s look at another example of a client-server relationship. On the left is your computer,

or perhaps your smartphone, whatever you’re using to watch this video. On the right is

a YouTube server which contains this video. What do you think the blue cloud in the middle

represents?

The answer is, The Internet. In network diagrams, a cloud is often used to represent the Internet,

or in any situation where the details of that part of the network aren’t necessary. The

Internet is a very complex network, and for the sake of this diagram all we need to know

is that data from your computer passes through the Internet to reach the YouTube server.

The exact details of the Internet aren’t important for this diagram, so we can simply

use this cloud to represent the Internet.

So, your computer sends a request to the YouTube server for this youtube page, including the

video.

And youtube’s server sends the data, passing through the Internet, back to your PC.

However, YouTube doesn’t send the data all at once.

It sends you a stream of data until you’ve watched the whole video.

For one more example, let’s say your want to get a video from your friend. You both

have iphones, so you ask him to send you the video by airdrop.

Your phone requests the video.

And his phone responds, sending the video. You probably know it by know, but which phone

is the client and which is the server?

As you probably guessed, your phone on the left is the client.

And your friend’s phone on the right is the server.

To review once more. A client is a device that accesses a service made available by

a server. And, a server is a device that provide functions

or services for clients. Also, keep in mind the same device can be a client in some

situations, and a server is other situations.

Okay, hopefully you have a better idea of what a client is and what a server is. Now

let’s build out the network further, and show the next part of the connection between

end hosts and the Internet. Let’s say this is a network for an Enterprise,

and this Enterprise has a branch in New York, and a branch in Tokyo. Of course, a real Enterprise

branch will have more than just a couple PCs or a couple servers, but I also couldn’t

fit an entire network on this one slide! Typically you don’t connect end hosts like

PCs or servers directly to each other. You aggregate the connections to a device called

a switch.

As you can see, the two PCs are connected to SW1, and the two servers are connected to

SW2. Switches have lots of interfaces for you to connect end hosts to.

Look at this Cisco Catalyst switch. As you can see, lots of interfaces, or ports, to

plug your PCs or servers into. Switches are used to forward traffic within

a LAN, a local area network.

PC1 and PC2, as well as other devices plugged into SW1,

such as a network printer, or another PC, all reside on the same local area

network. The same goes for any devices connected to SW2 in the Tokyo Branch.

So, we have one LAN on the left, and one LAN on the right. The hosts within each LAN can

send data to each other, for example PC1 to PC2.

However, these switches cannot connect directly to the Internet.

And send data between the two LANs.

So let’s talk more about switches. Here on the left is the same Cisco switch from

the last slide. It’s a Catalyst 9200 model switch. On the right is a Catalyst 3650 model

switch. Catalyst switches are Cisco’s enterprise-grade switches, used by many enterprises to connect

their LANs. Now let’s review some characteristics of

switches.

Switches have many network interfaces or ports for end hosts, such as PCs, to connect to,

usually 24 or more.

Switches provide connectivity to hosts within the same LAN, meaning Local Area Network.

We’ll cover the details of LANs later, but for now just know it means end hosts within

the same area, like a bunch of computers on one floor of an office, or perhaps an entire

small office, or your home network.

Finally, switches do not provide connectivity between LANs or over the Internet. To do so,

we need another kind of network device.

That device is a router.

We can connect the switches to routers like this, and then connect the routers to the

Internet.

When end hosts in the New York Branch LAN want to communicate with end hosts in the

Tokyo Branch LAN, they will send the data to their router, R1, which will then forward

it to the Tokyo Branch LAN via the Internet. For example, if PC1 in the New York Branch

wants a file on SRV1 in the Tokyo Branch, it will send the request to R1 via SW1, which

will forward it over the Internet to R2, which will then send it to SRV1 via SW2.

The reply will then follow the reverse path back to PC1.

So, let’s talk about some of the characteristics of routers.

These are a few examples of Cisco routers you might find in use in an enterprise network.

The ISR 1000 and ISR 4000 have their network interfaces on the back, but if you look at

the ISR 900 you can probably notice a difference between a router and a switch. Let’s bring

up one of the switches we looked at before.

Compared to this Catalyst 9200 series switch, the ISR 900 router has relatively few network

interfaces. That’s one characteristic of routers compared to switches.

Routers have fewer network interfaces than switches.

Also, remember that switches are used to forward data within a LAN. Routers do the opposite.

Routers are used to provide connectivity BETWEEN LANs. And, because of that,

Routers are therefore used to send data over the Internet.

Here’s our network once again, but this time there’s a difference..

There is an attacker somewhere in the Internet, with an arsenal of many ways he could attack

our networks to steal information or otherwise damage our Enterprise. Although routers can

also provide some basic security features, what we should really be using to protect

our networks is…

A firewall. Firewalls are specialty network security devices that control network traffic

entering and exiting your network. Firewalls can be placed ‘outside’ of your router,

like FW1, or ‘inside’ of your network, like FW2. What’s important is that they

protect the end hosts inside, like the PCs and Servers in this network. Firewalls must

be configured with security rules to determine which network traffic should be allowed and

which should be denied. If you configure the rules properly, if PC1 in the New York Branch

tries to access SRV1 in Tokyo, the firewalls should permit the traffic through.

The return traffic from SRV 1 to PC1 should be allowed as well.

However, if the attacker tries to access anything inside of our networks, the firewall should

block it.

So let’s look at a couple of Cisco’s firewalls. At the top here are two examples of Cisco

firewalls. On the left is an ASA5500-X series firewall. The ASA, or adaptive security appliance,

is Cisco’s classic firewall. Although the ASA is their classic firewall, modern

ASAs include modern features of so-called ‘next generation firewalls’, including

things like IPS or intrusion prevention system. You’ll hear a lot more about that in the

security section of this course. On the right is a Firepower 2100 series firewall. This

is a next-generation firewall as well. Okay, let’s review some characteristics

of firewalls.

Firewalls monitor and control network traffic based on configured rules. You explicitly

configure which network traffic should be allowed in to your network, and which should

not.

Firewalls can be placed ‘inside’ the network or ‘outside’ the network. Meaning, the

firewall can filter traffic before it reaches the router, or after it has passed through

the router. In some cases, you might have a firewall inside and outside the network!

Firewalls are known as ‘next-generation firewalls’ when they include more modern

and advanced filtering capabilties. Both of these Cisco firewalls are considered ‘next-generation

firewalls’. Now, I have one more thing to look at regarding firewalls.

What about the firewall on your computer? Let’s take a brief look.

The two firewalls we looked at in the previous slide are network firewalls. Network firewalls

are hardware devices that filter traffic between networks. These are the kind of firewall we

will focus on in this course, as it is a networking course. However, there are also Host-based

firewalls. Host-based firewalls are software applications that filter traffic entering

and exiting a host machine, like a PC. Your PC almost certainly has a software firewall

installed, as it should. Even in a network with a hardware firewall, each PC should include

a software firewall as an extra line of defense.

Okay, now we’re back to our definition of a network. Do you understand more about each

of these types of network nodes? Keep in mind, there are other kinds of network devices, and

we’ll cover some of those later in this course. Stay tuned for this lecture’s supplementary

materials which will help you review and test your knowledge. In the next lecture we will

look at the next two sentences of this Wikipedia definition of a computer network, focusing

on the various kinds of connections between these network devices.

For this lecture, and all other lectures, there will be supplementary materials to help

you practice and improve your understanding. There will be three primary resources:

End-of-video quizzes after each video. This video’s quiz will be coming up right after

this slide.

There will also be pre-made flashcards to review the

lecture’s material, using the

flashcard software ‘Anki’. These flashcards will be included in the description of each

video. Since this is the first video, however, I will make a separate video explaining how

to download and use the Anki software. If you already know how to use Anki, feel free

to download this video’s flashcards in the description and get started. Otherwise, wait

for the next video and I’ll show you how. Just one recommendation: As I will upload a

separate flashcard deck for each video, instead of having many separate decks, I recommend

you create one CCNA deck and then transfer the new cards to that central deck.

Finally, there will be a practice lab using Cisco’s network simulation software ‘Packet

Tracer’ for each and every video. I will release separate videos for these practice

labs, and will include the packet tracer file in the descriptions of those videos so you

can download them, and complete them yourself. The packet practice lab for this video will

be a demonstration of how to download packet tracer and get started with it.

Now, let’s go on to this video’s quiz. Select the best answer from the available

choices. In some cases there are multiple answers that could possibly be correct, but

there will always be one best choice. Cisco exams tend to have lots of questions like

that, so hopefully some of these will be able to test you in a similar manner. This first

video’s quiz questions, however, shouldn’t be too difficult.

Your company wants to purchase some network hardware to which they can connect the 30

PCs in your department. Which type of network device is appropriate? A, a router. B, a firewall.

C, a switch. Or D, a server. Pause the video to think about your answer. The answer is

C, a switch. Let’s analyze each of the incorrect answers first, then the correct answer.

A router, like this Cisco ISR 900 series router, is designed for forwarding traffic between

networks, not for connecting lots of end hosts like PCs to.

Also, a router will not typically have 30 network interfaces to connect hosts to.

So, A, a router, is incorrect.

A firewall, like this Cisco ASA 5500-X series firewall, is designed to filter traffic as

it enters and exits the local network. It is not designed to connect directly to end

hosts, and typically will not have enough network interfaces for 30 hosts.

So, B, a firewall, is incorrect.

A server is an end host itself, not a networking device to which you will connect other end

hosts. So, D, a server, is incorrect.

A switch, like this Cisco Catalyst 9200 series switch, is designed to connect many end hosts

in the same LAN together. They include many network interfaces to connect hosts to.

So, C, a switch, is the correct answer. Okay let’s go on to the next question.

You received a video file from your friend’s Apple iPhone using AirDrop. What was his iPhone

functioning as in that transaction? A, a server. B, a client. Or C, a local area network. Pause

the video to think about your answer.

The answer is A, a server. Lets’ check the answers.

In this case your iPhone, not your friend’s iPhone.

A client accesses a service, it does not provide a service.

So, B, a client, is incorrect.

An end host like an iPhone does not function as a local area network (LAN) by itself. It

can, however, be a part of a local area network. So, C, a local area network, is incorrect.

A server is a device that provides functions or services for clients.

In this case, your friend’s phone provided the file to your iPhone.

So, A, a server, is the correct answer. Let’s go to the next question.

What is your computer or smartphone functioning as while you watch this video? A, a server.

B, an end host. Or C, a client. Pause the video to think about your answer. The answer

is C, a client. Let’s check the answers.

Your device is receiving a service, not providing one, so it is not functioning as a server.

Therefore A, a server, is incorrect.

Although your device is an end host, that does not describe its function. Both servers

and clients are end hosts in a network. So, B, an end host, is incorrect.

Your device is receiving a service from YouTube’s servers. Therefore, it is functioning as a

client. So, C, a client, is the correct answer. Let’s

go to the next question.

Your company wants to purchase some network hardware to connect its separate networks

together. What kind of network device is appropriate? A, a firewall. B, a host. C, a LAN. Or D,

a router. Pause the video to think about your answer.

The answer is D, a router. Let's check.

Although a firewall can connect multiple networks together, its real purpose is to monitor and

control traffic as it enters and exits the network.

So, A, a firewall, is not the best answer.

The term ‘host’ can refer to any type of network node. So B, a host, is incorrect.

LAN stands for Local Area Network. A LAN is not a network device itself. So, C, a LAN,

is incorrect.

A router is a device that is designed to connect and forward network traffic between multiple

networks. So, D, a router, is the correct answer. Let’s go to the final quiz question

for this video.

Your company wants to upgrade its old network firewall that has been in use for several

years to one that provides more advanced functions. What kind of firewall should they purchase?

A, a host-based firewall. B, a next-level firewall. C, a next-generation firewall. Or

D, a top-layer firewall. Pause the video to think about your answer.

The answer is C, a next-generation firewall. Let’s check each answer.

A host-based firewall is a piece of software that runs on an end host, like the firewall

on your computer. It is not a network firewall. So A, a host-based firewall, is incorrect.

Next-level and Top-layer are not actual types of firewalls, so B and D are incorrect.

A next-generation firewall combines traditional firewall features with more advanced filtering

functionalities. So C, a next-generation firewall, is correct.

Thank you for watching! That’s all for this video. If you want to show your support, please

subscribe to the channel, like the video, leave a comment, and share the video with

anyone else studying for the CCNA. I also accept donations via cryptocurrency or Patreon

via the links in the description. That’s all for now.