Studying for CCNA Update...

Studying for CCNA Update

It has been a while since I have written a post about studying for Cisco's CCNA IT certification.

To be honest, progress has been slow.

However, there are reasons for that.

Back in late December 2024, I had just completed the reading the following chapters in the CCNA 200-301 Official Cert Guide, Volume 1, Second Edition by Wendell Odom, CCIE No. 1624.

• Part One: Introduction to Networking
• Chapter 1: Introduction to TCP/IP Networking
• Chapter 2: Fundamentals of Ethernet LANs
• Chapter 3: Fundamentals of WANs and IP Routing
• Part Two: Implementing Ethernet LANs
• Chapter 4: Using the Command-Line Interface
• Chapter 5: Analyzing Ethernet LAN Switching
• Chapter 6: Configuring Basic Switch Management
• Chapter 7: Configuring and Verifying Switch Interfaces

I also completed the exercises for Chapters 4, 5, 6, and 7 in Pearson Vue's CCNA Network Simulator training program. Furthermore, I even completed all of the exercises for Chapters 4, 5, 6, and 7 on Wendell Odom's CCNA Skills Blog. Do you need to use Pearson Vue's CCNA Network Simulator while studying for the CCNA IT certification? No, you don't. However, the CCNA Network Simulator does come with A LOT of guided practice exercises to get you experience using Cisco's IOS command-line interface for configuring switches and routers. In other words, using Pearson Vue's CCNA Network Simulator is completely optional. However, I believe that the money spent on Pearson Vue's CCNA Network Simulator is money well spent.

For CCNA study, Wendell Odom's CCNA Skills Blog is also entirely optional. The CCNA Skills Blog contains a lot of good resources for studying CCNA. Moreover, the CCNA Cert Skills Blog also features Wendell Odom's own CCNA practice exercises. While Pearson Vue's Network Simulator is a simulation, Wendell Odom's networking exercises require you to use Cisco's Packet Tracer program. Unlike the Network Simulator, Wendell Odom's networking exercises are entirely free. Plus, Cisco offers Packet Tracer as a free download from its website. You do have to create an account with Cisco to download Packet Tracer, however. It's irritating, but Packet Tracer is an invaluable program to have in your CCNA study.

What was the problem?

Despite reading the first seven chapters in the textbook and completing all of the exercises, what was the problem?

Since I had recently earned four training badges from Cisco Networking Academy (see previous post here), I was probably feeling a little too high and mighty when it came to basic networking. Thus, when it came to reading Chapters 4, 5, 6, and 7 in the CCNA 200-301 Official Cert Guide, I just read through the chapters without taking any notes. I was about to start Chapter 8: Implementing Ethernet Virtual LANs, when I realized that I probably committed a mistake by not taking any notes while reading those four chapters.

Chapter 4 from the CCNA Official Cert Guide

Chapter 5 from the CCNA Official Cert Guide

Chapter 6 from the CCNA Official Cert Guide

Chapter 7 from the CCNA Official Cert Guide

Thus, I made the decision to RE-READ all four chapters and TAKE COPIOUS NOTES. After re-reading each individual chapter, I went back to the Pearson Vue Network Simulator and completed the exercises for each chapter. To be sure, it was A LOT of work and required a lot of extra time. However, it was a necessary review to complete.

Chapter 8 from the CCNA Official Cert Guide

After all of that hard work, I was ready to start reading Chapter 8: Implementing Ethernet Virtual LANs. This time, there would be a difference, however. I would take notes as I read through the chapter. Predictably, taking notes while reading prolonged the amount of time it would have taken to complete the chapter if I had just read it. In the Introduction to the CCNA 200-301 Official Cert Guide, Wendell Odom mentioned that he tried to write each chapter so that it would take approximately an hour to read. That was an interesting comment, I thought. Whenever I read something technical, I tend to read slowly as I try to absorb all of the information. At over 30 pages, Chapter 8 is one of the longest chapters in the CCNA 200-301 Official Cert Guide. 

Why is Chapter 8 so long? Well, the chapter covers two topics. The first topic concerns what are known as virtual LANs. What is a virtual LAN? A virtual LAN is created when you essentially subdivide a switch into smaller segments. A typical switch has 24 ports. For example, let's say you have a small business with several departments, but you only have several departments, such as accounting, operations, sales, human resources, and so on. To improve security and network efficiency, you decide to group all of the devices used by the accounting department into a specific range of ports. Then, you do the same for all of the other departments. There is a problem. When you create a virtual LAN, the switch recognizes each virtual LAN as a separate network. You can't just send a message from a device on VLAN 1 to another device on VLAN 2 even though you are using the same switch. It just won't work. To send a message to another device on another VLAN on the same switch, you need a router. After all, the VLANs are located on different networks. That's where trunking comes in. Essentially, trunking identifies what VLAN the message is being sent to. Thus, you have to adjust the settings on the switch and the router to enable trunking, which will then allow devices on separate VLANs to send messages to each other. 

Yes, it's A LOT of information to digest as you are taking notes. However, I eventually made it to the end of the chapter. When you take notes while reading, the process makes you concentrate on what you are reading.   

Pearson Vue Network Simulator Chapter 8 Exercises

Now that I have completed reading and taking notes on Chapter 8 in the CCNA 200-301 Official Cert Guide, I have been slowly completing all of the Network Simulator exercises for Chapter 8. The Network Simulator contains three types of exercises for Chapter 8. 

• Skill Builders
• Configuration Scenarios
• Troubleshooting Scenarios

So far, I have completed all 13 Skill Builder exercises. I recently completed all three Configuration Scenarios. Now, I just need to complete the remaining four Troubleshooting Scenarios. Once all of the Network Simulator labs are complete, it will then be time to either move on to Chapter 9: Spanning Tree Protocol Concepts or head on over Wendell Odom's CCNA Skills Blog and work my way through his VLAN exercises. 

Sounds like fun, doesn't it?  

Finishing Chapter 7 in the Official Cert Guide for CCNA

Working My Way Through the CCNA Official Cert Guide

A couple of weeks ago, I went ahead and began studying for the Cisco Certified Network Administrator certification. This IT certification is better known by its abbreviation: CCNA. As I mentioned in a previous post on here on my blog, when I worked at the Social Security Administration (SSA) in Woodlawn, MD as a Tier 1 help desk agent, I made an attempt to study for the Network+ certification offered by CompTIA. Due to the sheer volume of information required to know for the certification, I gave up on studying for Network+. I then made an attempt at studying for the CCNA certification. I got as far as either Chapter 9: "Spanning Tree Protocol Concepts" or Chapter 10: "RSTP and EtherChannel Configuration" before stopping. I was having trouble understanding some of the topics in either chapter, so I got bogged down studying. In addition, I went through a period where I got REALLY BUSY with work. It's amazing how that works.

Over the past year, I have been taking online courses via Cisco's Networking Academy. Since I recently completed all four online classes for networking, it seemed like the perfect time to make another attempt to study for (and earn) the CCNA certification from Cisco.

A couple of months ago, I discovered on Cisco's own website that an updated and revised version of the Official Cert Guide for CCNA 200-301 would be published and available for sale in July 2024. Well, the first volume would be available. At the time, the second volume of the Official Cert Guide had been scheduled to be published a month or two after. Even though I was busy working on the online courses at the Cisco Networking Academy, I went ahead and bought the first volume of the new certification guide from Amazon as soon as it was available for purchase.

Since I decided to make another attempt to pass the CCNA certification exam, I quickly made it through Part 1: "Introduction to Networking". Part 1 consists of the following chapters:

• Chapter 1: Introduction to TCP/IP Networking
• Chapter 2: Fundamentals of Ethernet LANs
• Chapter 3: Fundamentals of WANs and IP Routing

To be honest, Part 1: "Introduction to Networking" was a good review of the information covered in the four online networking classes that I had completed.

I then began work on Part 2: "Implementing Ethernet LANs", which consists of the following chapters:

• Chapter 4: Using the Command-Line Interface
• Chapter 5: Analyzing Ethernet LAN Switching
• Chapter 6: Configuring Basic Switch Management
• Chapter 7: Configuring and Verifying Switch Interfaces

I then made short work reading chapters 4, 5, 6, and 7. Like the chapters in Part 1: "Introduction to Networking", chapters 4, 5, 6, and 7 were another good review. However, using the Cisco IOS to configure different aspects of a network switch is like riding a bike to a certain degree. Part of my plan for studying for the CCNA certification is to use Network Simulator software offered by Pearson Vue. The objective of the Network Simulator tool is to give you experience using Cisco IOS by giving you exercises to work on after reading the corresponding chapter in the Official CCNA Cert Guide. Just know that the Network Simulator tool doesn't have exercises for every chapter in the Official CCNA Cert Guide. It just depends on whether the chapter in the Official CCNA Cert Guide covers new commands for the Cisco IOS.

On the night of December 11, 2024, I completed the exercises in Pearson Vue's Network Simulator tool for Chapter 7: "Configuring and Verifying Interfaces". Surprisingly, there were only three exercises for the chapter.

Before moving on to Part 3: "Implementing VLANs and STP", there are some things that I probably should do first.

In no particular order, here are some things that I should do:

• Go back and complete the "Do I Know This Already?" quizzes for chapters 4, 5, 6, and 7. The questions are probably very similar to the questions on the official CCNA certification exam. As a result, the more practice I can get with these types of questions, the better.
• Go to Wendell Odom's Cert Skills blog and work my way through the exercises for chapters 4, 5, 6, and 7. These exercises are similar to the Cisco IOS exercises found on Pearson Vue's Network Simulator. The difference is that Wendell Odom doesn't prompt you or guide you through the exercise. Instead, he gives you the network setup and tells you the changes that need to be made. It's up to you to try to figure out what commands that you need to enter into the Cisco IOS command prompt to complete the exercise. Wendell Odom does give you the answers. The nice thing about the Cisco IOS exercises available on the Cert Skills blog is that the exercises are free. While the exercises were conceived with using just a pen and a piece of paper, you can complete the exercises using Cisco's Packet Tracer application, which is available for free.

Screenshot of Wendell Odom's Cert Skills blog.

• Create my own User's Guide to the Cisco IOS. That means going through chapters 4, 5, 6, and 7 creating my own tables of all of the Cisco IOS commands. There are also step-by-step instructions on how to configure passwords, for example. Once complete, I can then print out all of the tables and step-by-step guides and then put them into a notebook. Then, it's just a matter of adding additional tables and step-by-step guides as I complete subsequent chapters in the Official CCNA Cert Guide.

Cisco IOS User Guide on Google Docs.

UPDATE: Over the past week or so, I have been steadily creating my own Cisco IOS user guide over on Google Docs. I created my versions of the tables found in the first seven chapters of the <b>Official CCNA Cert Guide</b>. I am planning on adding to this document as I progress through the book.  

• Go back through chapters 4, 5, 6, and 7 and write down notes for all of the key topics that MIGHT be on the certification exam. So far, I have written down notes for chapter 4. Since I have completed those four online networking classes from the Cisco Networking Academy, this is largely just another review.
• Create my own simple networks using Cisco Packet Tracer and then configure all of the devices. The nice thing about this option is that Cisco Packet Tracer is F-R-E-E to download and use. Here on my blog, I wrote a post about other options available, such as Cisco Modeling Labs or GNS3, if you don't want to use Cisco Packet Tracer.

Cisco Packet Tracer exercise. 

Lastly, is it really necessary to buy your own hardware to study for CCNA? That is, do you need to buy a router, a couple of switches, some Ethernet cable, and a networking cabinet? Not really. If you have the money and space, you most certainly can. Based on my own research, a hardware kit for CCNA study can easily cost several hundreds of dollars, depending on the options you choose. However, it's not necessary to buy all of that equipment. I have a friend and former co-worker at SocialSecurity who earned the CCNA certification by just using Packet Tracer. The main advantage of buying your own CCNA hardware kit is that you gain tactile experience using and configuring hardware. Cisco Packet Tracer was designed for study when hardware is not available or affordable. Besides, the Cisco IOS used on Packet Tracer is largely the same (for the most part) as the Cisco IOS used by actual switches and routers.

New Badge from Cisco Networking Academy...

New Badge from Cisco Networking Academy

I recently earned a new badge from Cisco Networking Academy.

I F-I-N-A-L-L-Ypassed the final exam for the Network Support and Security online course.

The Network Support and Security course is the final online course offered by the Cisco Networking Academy for networking.

The four networking courses are (in order of completion):

1. Networking Basics
• Badge issued on January 23, 2024
• Skills learned: Network Media, Application Layer Services, Network Types, IPv4 Addresses, Wireless Access, Protocols Standards
2. Networking Devices and Initial Configuration
• Badge issued on April 18, 2024
• Skills learned: ARP, Cisco IOS, IPv4 Subnetting, DCHP, Hierarchical Network Design, Cisco Devices, Ethernet Operates, Network Layer Protocols, DNS, Binary Systems, Transport Layer Protocols, Virtualization and Cloud Services
3. Network Addressing and Basic Troubleshooting
• Badge issued on July 5, 2024
• Skills learned: Cisco Routers, IPv6 Addressing, Network Troubleshooting, Cisco Switches, Troubleshooting, Copper and Fiber Cabling
4. Network Support and Security
• Badge issued on October 29, 2024
• Skills learned: Documentation, Support, User Support, Endpoint Devices, Help Desk, Network Troubleshooting

Here are the badges.

Verified Cisco Networking Academy Networking Basics Badge

Verified Cisco Networking Academy Networking Devices and Initial Configuration Badge

Verified Cisco Networking Academy Network Addressing and Basic Troubleshooting Badge

Verified Cisco Networking Academy Network Support and Security Badge

All of my badges can be found on my public profile page at Credly. 

In addition, I need to go through and update both my LinkedIn profile page as well as my resume.

Now, it's on to my next learning course.  

I have yet to decide on what my next course should be. It could be CCNA, Python, JavaScript, Microsoft Server, or Microsoft Azure. 

Types of Firewalls...

It's a Long Slog

For the past few weeks, I have been S-L-O-W-L-Y working my way through the Network Support and Security online class from Cisco Networking Academy.

To be sure, it has been a L-O-N-G slog.

The course contains only three modules:

• Module 1: Network Support
• Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks
• Module 3: Network Security

Like all online classes from Cisco Networking Academy, each module contains several sub-modules. Each sub-module contains numerous definitions, charts, graphics, videos, pull-down menus, lists, and whatnot. If you are trying to take notes as you read each sub-module, it can be a time-consuming process.

When I started the Network Support and Security online course, my initial thought that it would be a quick and easy course to complete.

Boy, I was wrong.

Types of Firewalls

Sub-module 3.5.2 "Types of Firewalls" gives a basic introduction to four different types of firewalls.

The types of firewalls analyzed by the sub-module are:

• Packet Filtering (Stateless) Firewall

Packet Filtering (Stateless) Firewall 

• Packet filtering firewalls are usually part of a router firewall, which permits or denies traffic based on Layer 3 and Layer 4 information.
• Source IP address 
• Destination IP address
• Protocol
• Source port number
• Destination port number
• Synchronize/Start (SYN) packet receipt
• Packet filtering firewalls are stateless firewalls that use a simple policy table look-up that filters traffic based on specific criteria. 
• There are several advantages of using a packet filtering firewall:
• Packet filters implement simple "permit or deny" rule sets. 
• Packet filters have a low impact on network performance. 
• Packet filters are easy to implement and are supported by most routers.
• Packet filters provide an initial degree of security at the Network layer. 
• Packet filters perform almost all the tasks of a high-end firewall at a much lower cost.  
• There are several disadvantages of using a packet filtering firewall: 
• Packet filters are susceptible to IP spoofing. Threat actors can send arbitrary packets that meet Access Control List (ACL) criteria and pass through the filter. 
• Packet filters do not reliably filter fragmented packets. 
• Because fragmented IP packets carry the TCP header in the first fragment and packet filters filter on TCP header information, all fragments after the first fragment are passed unconditionally. 
• Decisions to use packet filters assume that the filter of the first fragment accurately enforces the policy. 
• Packet filters use complex ACLs, which can be difficult to implement and maintain. 
• Packet filters cannot dynamically filter certain services. 
• Packet filters are stateless. They examine each packet individually rather than in the context of the state of a connection. 
• Packet filters do not represent a complete firewall solution, but they are an important element of a firewall security policy. 

• Stateful Firewall

Stateful Firewall

• Stateful firewalls are the most versatile and most common firewall technologies in use. 
• Stateful firewalls provide stateful packet filtering by using connection information maintained in a state table. 
• Stateful filtering is a firewall architecture that is classified at the Network layer. 
• Stateful firewalls also analyze traffic at OSI Layer 4 (Transport) and Layer 5 (Session).
• There are several benefits to using a stateful firewall in a network: 
• Stateful firewalls are often used as a primary means of defense by filtering unwanted, unnecessary, or undesirable traffic. 
• Stateful firewalls strengthen packet filtering by providing more stringent control over security. 
• Stateful firewalls improve performance over packet filters or proxy servers. 
• Stateful firewalls defend against spoofing and DoS attacks by determining whether packets belong to an existing connection or are from an unauthorized source. 
• Stateful firewalls provide more log information than a packet filtering firewall. 
• Stateful firewalls also present some limitations: 
• Stateful firewalls cannot prevent Application layer attacks because they do not examine the actual contents of the HTTP connection. 
• Not all protocols are stateful. For example, UDP and ICMP do not generate connection information for a state table, and, therefore, do not garner as much support for filtering. 
• It is difficult to track connections that use dynamic port negotiation. 
• Some applications open multiple connections. 
• This requires a whole new range of ports that must be opened to allow this second connection. 
• Stateful firewalls do not support user authentication. 

• Application Gateway Firewall

Application Gateway Firewall

• An application gateway firewall (proxy firewall) filters information at Layers 3, 4, 5, and 7 of the OSI reference model. 
• Most of the firewall control and filtering is done in software. 
• When a client needs to access a remote server, it connects to a proxy server. 
• The proxy server connects to the remote server on behalf of the client. 
• Therefore, the server only sees a connection from the proxy server. 

• Next Generation Firewall

Next Generation Firewall

• Next generation firewalls (NGFW) go beyond stateful firewalls by providing the following: 
• Integrated intrusion prevention. 
• Application awareness and control to see and block risky apps. 
• Upgrade paths to include future information needs. 
• Techniques to address evolving security threats. 

Additional types of firewalls include:

• Host-Based (Personal and Server) Firewall - a PC or server with firewall software running on it. 
• Transparent Firewall - filters IP traffic between a pair of bridged interfaces. 
• Hybrid Firewall - a combination of the various firewall types. 

I will come back to this post after I complete Module 3.5 Firewalls and Host-Based Intrusion Prevention.

There is a lot of good information about firewalls.

Additionally, I found some really good information and graphics about the different types of firewalls over at Palo Alto Networks' webpage.

As always, more to follow.

Starting Module 3 Network Security...

Starting Module 3 Network Security

The other day, I FINALLY made it to "Module 3: Network Security" in the Network Support and Security online course from Cisco Networking Academy.

Boy, it was a long SLOG to get through "Module 2: Cybersecurity Threats, Vulnerabilites, and Attacks".

I will have more to write about this later.

Module 3: Network Security

Module Objective: Configure secure user access on a network.

Here are the objectives for Module 3:

Topic Title	Topic Objective
Security Foundations	Explain foundational security concepts.
Access Control	Configure access control.
Defending Systems and Devices	Explain cybersecurity processes and procedures that protect systems.
Antimalware Protection	Explain methods of mitigating malware.
Firewalls and Host-Based Intrusion Prevention	Explain how firewalls operate to filter traffic and recommend endpoint security measures.
Secure Wireless Access	Configure basic wireless security on a home router (WPAx).

Cybersecurity Threats, Vulnerabilities, and Attacks, Part 2...

Cybersecurity Threats, Vulnerabilities, and Attacks, Part 2

I haven't been posting a whole lot here on my blog.

I had completed two rather lengthy posts on my blog. It took a lot of effort to complete those two posts. There are additional lengthy posts in the pipeline.

Recently, I have been busy doing everything else except for posting to my blog.

One thing that I have been spending A LOT of time on is the Network Support and Security online class from Cisco Networking Academy.

For the past couple of weeks, I have been working my way through "Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks". In fact, I wrote a post right here on my blog about beginning the second module of the Network Support and Security online class. You can read that post right here.

To say that my progress through the course has been slow is an understatement.

As I mentioned in a short post that I published on LinkedIn, I have already been exposed to a significant portion of the information about cybersecurity threats due to security briefings I had been given while in was in the Army, worked as a DoD contractor, and as an IT help desk employee at the Social Security Administration. However, it is a lot of information to absorb, so it is a good idea to review the nature of cyber attacks from time to time.

Module 2.0 Introduction

Module 2.1 Common Threats

Module 2.2 Deception

Module 2.3 Cyber Attacks

Module 2.4 Wireless and Mobile Device Attacks

I just started working on "Module 2.5 Application Attacks". It is the last section for Module 2:  Cybersecurity Threats, Vulnerabilities, and Attacks. 

Module 2.5 Application Attacks

Cybersecurity Threats, Vulnerabilities, and Attacks

Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks

OK. I F-I-N-A-L-L-Y made it through "Module 1: Network Support" to "Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks" in the Network Support and Security online class available from the Cisco Networking Academy.

Boy, was it a LONG slog. However, "Module 1: Network Support" is complete. I scored a 93% on the 15 question end-of-module exam. I am now moving on to the next module in the class.

Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks

Here are the Topic Titles and Topic Objectives for Module 2. 

Topic Title	Topic Objective
Common Threats	Explain the threats, vulnerabilities, and attacks that occur in the various domains.
Deception	Describe the different deception methods used by attackers to deceive their victims.
Cyber Attacks	Describe common types of network attacks.
Wireless and Mobile Device Attacks	Describe common types of wireless and mobile device attacks.
Application Attacks	Describe types of application attacks.

Cisco CyberOps Associate

After "Module 2: Cybersecurity Threats, Vulnerabilities, and Attacks", Module 3 covers the topic of network security. As a result, the last two modules of the Network Support and Security online class will have a cybersecurity emphasis.

I recently bought a copy of official study guide for the Cisco CyberOps Associate (CBROPS 200-201) book published by Cisco Press over on Amazon.com. Thus, it will be interesting to see how much of an overlap there is between the online course and Cisco's entry-level cybersecurity certification.

Textbook for Cisco CyberOps Associate

Recently, I have considered putting aside studying for CCNA and focusing on the Cisco CyberOps Associate certification instead. After all, the Cisco CyberOps Associate certification only has one textbook compared to the two volumes needed to study for CCNA. Furthermore, I have a lot of regret about not earning my Security+ certification from CompTIA. After I earned my A+ certification, I should have just started studying for the Security+ certification in order to get me out of working at the Tier 1 IT help desk at the Social Security Administration (SSA). Earning that Security+ certification would have allowed me to work in the Security Operations Center (SOC) for SSA as a cybersecurity analyst. Instead of doing that, I got bogged down studying for the Network+ certification, which is CompTIA's version of CCNA. Why did I start studying for Network+ after A+? Well, the conventional wisdom is to study for Network+ after earning the A+ certification. After earning the Network+ certification, people will then typically study for Security+. The certification model is computer (A+) then network (Network+) then security (Security+). After figuratively banging my head against a brick wall while studying for Network+, I gave up and then started to study for CCNA instead. In hindsight, I should have skipped over networking altogether and focused exclusively on cybersecurity. That said, in order to defend networks from cyberattacks, it does kind of help to know how networks operate and do what they do.

Do I have regrets?

You better believe it.

Possible Change of Mission

Once I finish the Network Support and Security online course, I just MIGHT put aside studying for CCNA and focus on studying for the CyberOps Associate certification instead.The reason? The main reason is that I NEED an IT certification to put on my resume AS SOON AS POSSIBLE.

On the other hand, I just might be able to land an entry-level data center technician job somewhere in the Phoenix area with these badges I have earned from completing the online courses in networking from the Cisco Networking Academy.

We will just have to see what happens next.

PuTTY, WireShark, and NMAP

PuTTY, Wireshark, and NMAP

This will be a post about the following IT applications: PuTTY, Wireshark, and NMAP.

As I am working my way through "Module 1: Network Support" in the Network Support and Security online class available at the Cisco Networking Academy, I became reacquainted with the IT applications Wireshark and NMAP. Since I recently wrote about it, I also became reacquainted with the IT application PuTTY.

What is PuTTY?

Due to my recent post about my first IT job, I recently downloaded a copy of the PuTTY application onto my Dell laptop. What does PuTTY do and what is it used for? Here is a good description:

PuTTY is a free and open-source terminal emulator, serial console and network file transfer application. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a serial port. The name "PuTTY" has no official meaning.

In so many words, with PuTTY running on your computer (laptop or desktop), you can connect to a switch, a router, or a host and make changes to the configuration.

With PuTTY, you can connect to a host, a router, or a switch using a computer protocol called Telnet. It's not recommended that you use Telnet, however. Telnet does not encrypt user names and passwords. As a result, if someone was monitoring your activity with a packet sniffer, such as Wireshark (see below), he or she would be able to determine your logon credentials. Telnet dates from the 1970s and 1980s when computer security had a low priority since users were U.S. government employees.

As a result of this flaw with Telnet, it is highly recommended that you use a computer protocol known as Secure Shell, or SSH. SSH will encrypt your logon user name and password, making it rather difficult for potentially malignant actors to eavesdrop on your data.

Is there a reason for using PuTTY at home? Well, the main draw with an application like PuTTY is that it is an open-source application that is independent of any software or hardware vendor. Unless you have your own collection of servers and routers at home, such as for studying for Cisco's CCNA certification, you might find that PuTTY is of limited use.

That said, there could be instances where you could use PuTTY at home. This might be a subject worth pursuing at some point.

I am slowly making my way through the Network Support and Security online course from the Cisco Networking Academy. In Section 1.5 "Troubleshoot a Network", there are a couple of hands-on labs that utilize both Wireshark and NMAP.

Screenshot of PuTTY interface.

What is Wireshark?

What is NMAP?

I just downloaded and installed NMAP onto my computer. I cannot wait to try it out.

Screenshot of NMAP using the command prompt option.

Screenshot of NMAP's graphical user interface (GUI) known as Zenmap.

More to follow.

UPDATE: I'm going to have to re-write this post. 

New Cisco Networking Academy Class...

New Cisco Networking Academy Class

This week, I dropped the AI Fundamentals with IBM SkillsBuild online class at the Cisco Networking Academy.

Introduction to Artificial Intelligence with IBM SkillsBuild 

I completed the first module, "Introduction to Artificial Intelligence". It was interesting to learn about what artificial intelligence is and what it is not. It was also interesting to learn about the history of artificial intelligence and its different categories. It was also interesting to learn about the different techniques on how machine learning solves problems. As you progress through the class, you eventually work with IBM Watson AI to run a couple of simulations. It's all fascinating. Moreover, while AI may be the latest IT buzzword, AI isn't going away anytime soon. Thus, it's important to learn what it is and what it can do. My understanding is that the newest version of the Official Cert Guide for CCNA from Cisco Press will have a chapter about using AI in regards to networking.

However, since I have one last online course to complete all of the networking courses from Cisco Networking Academy, I made the decision to stop the AI Fundamentals with IBM SkillsBuild online class. Despite my newly found interest in the subject, the course itself is a distraction from my goal of completing the online courses for networking. I will come back and complete the course at a later date.

As a result, I went ahead and started the Network Support and Security online class instead.

Network Support and Security Online Course

While the Network Support and Security online class may only have three training modules, each individual module is quite lengthy.

Here are the three modules:

• Network Support
• Cybersecurity Threats, Vulnerabilities, and Attacks
• Network Security

Plus, as I mentioned in a previous post, I have a long list of online courses at the Cisco Networking Academy that I want to complete.

Time to get studying!!!

Completed Another Cisco Online Course...

Online Course Complete

On this past Friday, I F-I-N-A-L-L-Y completed the Final Exam for the Network Addressing and Basic Troubleshooting online course over at the Cisco Networking Academy.

Like other online courses I have taken at the Cisco Networking Academy in recent months, the Network Addressing and Basic Troubleshooting course was a long slog. Then again, while taking these online courses, I took serious and exhaustive notes. The notes I took during the online course filled an entire Lemome grid paper notebook. I worked through all of the Cisco Packet Tracer exercises. I also worked through the exercises that did not involve using Cisco Packet Tracer.

During the Final Exam, if I didn't immediately know the answer to a question, I carefully searched for the answer in my notes. Sometimes, it's like looking for a needle in a haystack. Oftentimes, the wording in the question and the answer exactly matches the wording given in the lecture notes. As so often happens in tests for IT subjects, there were one or two questions where the answer is ambiguous, so you have to try to narrow down the most likely answer and hope for the best. All .of that hard work paid off as I scored a 90% on the Final Exam.

Certification Badges on Credly

After getting the result of the Final Exam, I logged into Credly to check on my accomplishment. I now have a verified badge for Network Addressing and Basic Troubleshooting.

Verified Network Addressing and Basic Troubleshooting Badge

As a result, I now have three verified certification badges from Cisco Networking Academy on Credly.

The three verified certification badges that I have earned are:

• Networking Basics
• Networking Devices and Initial Configuration
• Network Addressing and Basic Troubleshooting

Verified Cisco Badges on Credly

Now, I just need to update my resume to reflect these achievements.

Next Courses to Take

With the Network Addressing and Basic Troubleshooting course completed, it's time to move on to the next online course.

Here is my list of online courses at Cisco Networking Academy that I am planning to take:

• Introduction to Artificial Intelligence
• JavaScript Essentials 1
• JavaScript Essentials 2
• Ethical Hacker
• Introduction to Cybersecurity
• Cyber Threat Management
• Python Essentials 1
• Python Essentials 2
• Network Support and Security
• Network Defense
• Endpoint Security

It's a long list.

To complete all of the online courses about networking, the next course I should start should be Network Support and Security. However, someone that I recently met via Twitter/X, who is something of an AI-enthusiast, has suggested that I learn about artificial intelligence (AI). As a result, I just might start the Introduction to Artificial Intelligence online course before I tackle the Network Support and Security online course.

From what I can tell, the Introduction to Artificial Intelligence is relatively short online course.

Since I could use a break from networking, I just might do that online course next.

That said, I really want to start the Python Essentials 1 online course.

As always, we'll see.

Cisco Troubleshooting Methods...

Cisco Troubleshooting Methods and Techniques

This week, I started "Module 7: Troubleshoot Common Network Problems" in the Network Addressing and Basic Troubleshooting online course from the Cisco Networking Academy.

Section 7.1 The Troubleshooting Process

Module Objective: Troubleshoot basic network connectivity issues.

Topic Title	Topic Objective
The Troubleshooting Process	Describe some of the approaches used to troubleshoot networks.
Physical Layer Problems	Describe the process of detecting physical layer problems.
Troubleshoot Wireless Issues	Troubleshoot a wirless network problem.
Common Internet Connectivity Issues	Explain common internet connectivity problems.
Customer Support	Explain how to use outside sources and internet resources for troubleshooting.

There will be more content added to this post as I work my way through the module.

Cisco Switches and Routers

Cisco Switches and Routers

For the past week, I have been working on "Module 6: Cisco Switches and Routers" in the Network Addresssing and Basic Troubleshooting online course from Cisco Networking Academy.

Module 6: Cisco Switches and Routers

The first half of the module covers Cisco switches.

Cisco Catalyst 9300 Series Switch

The second half of the module covers Cisco routers.

Cisco 4300 Series Routers

Section 6.1 Cisco Switches

Section 6.1 Cisco Switches

As routers and switches evolve, the distinction between them may seem to blur. The main difference between routers and switches:  

• LAN switches provide connectivity within the local-area networks of the organization.
• Routers interconnect local networks and are needed in a wide area network (WAN) environment.
• Definition: A switch is used to connect devices on the same network.
• Definition: A router is used to connect multiple networks to each other.

Other connectivity options for LANs include include the following:

• Wireless access points (WAPs) deployed in enterprises enable computers and other devices, such as IP phones, to wirelessly connect to the network, or share broadband connectivity.
• Firewalls guard against network threats and provide security, network control, and containment.

Key Point: When a LAN network grows to the point where the four Ethernet ports provided by the wireless router are not enough for all of the devices that need to attach to the wired network, it is time to add a LAN switch to the network.

A switch can provide connectivity at the access layer of a network, connecting devices to a LAN.

A switch can allow the network to grow without replacing central devices.

Factors to consider when choosing a switch to use for an enterprise network include:

• Type of ports
• When selecting a switch for your LAN, choosing the appropriate number and type of ports is critical.
• Most lower-cost switches support only copper twisted-pair interface ports.
• Higher priced switches may have fiber-optic connections.
• These are used to link the switch to other switches that may be located over long distances.
• Speed required
• Ethernet twisted-pair interfaces on a switch have defined speeds.
• A 10/100 Ethernet port can only function at either 10 megabits per second (Mbps), or at 100 Mbps.
• What this means is that even if the device that you are connecting to the 10/100 switch interface port is capable of connecting at gigabit speeds, the maximum speed at which it will be able to communicate will be 100 Mbps.
• Switches may also include gigabit Ethernet ports.
• If your internet connection is more than 100 Mbps, then a gigabit port is necessary to take advantage of the higher internet bandwidth.
• Gigabit Ethernet ports will also operate at 10/100 Mbps.
• Gigabit Ethernet is sometimes represented as 1000 Mbps.
• Example: The Cisco Catalyst 9300 48S switch has two 40 Gbps uplink ports to provide a fast path for the 48 ports to access the rest of the network and the internet.
• Similar to a switch port, Ethernet NICs operate at specific bandwidths such as 10/100 or 10/100/1000 Mbps.
• Key Point: The actual bandwidth of the attached device will be the highest common bandwidth between the NIC on the device and the switch port.
• Expandability
• Networking devices come in both fixed and modular physical configurations.
• Fixed configurations have a specific type and number of ports or interfaces.
• Modular devices have expansion slots that provide the flexibility to add new modules as required.
• Example: The Cisco Catalyst 9600 chassis in which you can install different configurations of hardware to address your particular environment.
• Manageability
• Many basic, inexpensive switches are not configurable.
• A managed switch that uses a Cisco operating system enables control over individual ports or over the switch as a whole.
• Controls include the ability to change the settings for a device, add port security, and monitor performance.
• Network administrators directly connect to a Cisco Catalyst switch using a console cable.

In addition to switches and routers, there are other connectivity options available for LANs. They include:

• Wireless Access Points (WAPs) that are deployed in enterprises enable computers and other devices, such as IP phones, to wirelessly connect to the network or share broadband connectivity.
• Firewalls guard against network threats and provide the following:
• Security
• Network control
• Containment

Section 6.2 Switch Speeds and Forwarding Methods

Section 6.2 Switch Speeds and Forwarding Methods

Section 6.3 Switch Booting Process

Section 6.3 Switch Booting Process

Section 6.4 Cisco Routers

Section 6.4 Cisco Routers

Section 6.5 Router Boot Process

Section 6.5 Router Boot Process

I am not too pleased with how this post turned out.

I will have to re-write it.

Sorry about that.