Cisco Powers the Internet
The internet is made up of millions of computers. When you think of computers, you probably think of the Desktop PC your reading this on or the Server hosting this website. It’s true, this is part of the internet. What you may or may not know depending on your technology background, is that in between the servers and clients are computers in the middle that connect them all together. Those computers are called Switches and Routers, and Cisco has a virtual stranglehold on that market.
The Internet is a BIG Market
Synergy has done research showing Cisco to have approximately 70 percent of the switching and routing market. When you consider that there are millions of these devices in the world, you can see the value that Cisco holds. At the time of this writing, it is an estimated $45 billion dollar per year market, and Cisco takes a 70% chunk of that.
Cisco Certification is good for Employment Opportunities
As a Cisco Certified Network Associate or CCNA, I can vouch for the benefits of having a background in Cisco Networking. With millions of Cisco devices in the world, and most every Fortune 500 company having Cisco gear in their network, it helps to have some applicable skills that are in demand from these companies. It helps to have a background in technology, computers, and possibly formal education at the college level in computer science, to get the ball rolling with your Cisco Studies. Ultimately though, it is going to take a strong curiosity about networking, and a willingness to commit to long hours of training via books, videos, and hands on Lab Exercises, before you actually have a grasp on the skill set.
So What Are These Switches and Routers?
Switches are what make Local Area Networks, or LAN’s, possible. Companies typically have several of these LAN’s or VLANs (Virtual LANS) in their local campus. Switches handle what is called Layer 2 Traffic. Layer 2 traffic deals with hardware or MAC addresses. The Ethernet switch is the foundation of computer networking.
Routers on the other hand operate at Layer 3 and deal with routing Internet Packets based on IP addresses. This is how the hundreds and thousands of LAN’s in the world get connected together, which is what ultimately results in the Internet you know and love. It’s just one massive collection of smaller LAN’s connected together via Routers. This is where Cisco really shines.
Where do I Begin?
That’s a good question. We’re going to assume you are a beginner and take it from the start. This may not be the case for you and if so, feel free to navigate away to more advanced topics online.
Begin with the CCENT level certification. This is Cisco’s base level certification and will get you started with the technology.
ICND1 is the course and exam that is required for this entry level certification and covers the following topics:
What is a Network?
Why do we need a network? What does the network accomplish for us? Without understanding this foundation, the rest of the Cisco certification track will not make much sense.
Living in the OSI World
If someone told you, “My car is broken,” but was unable to expand on what exactly was broken, you wouldn’t know where to begin looking for a solution. In the same sense, networks are an extremely complex system of communicating. The OSI Model holds the key to understanding the layers of network functionality.
Basic TCP/IP: Addressing Fundamentals
We live in a TCP/IP world. Having a thorough understanding of this protocol is critical to your success in any network environment. Learn the basics of TCP/IP and concepts such as IP address format, public and private addressing, and address classes.
Basic TCP/IP: TCP and UDP Communication
Every network-aware application has a choice to make when it communicates across the network – TCP or UDP? This decision determines how reliable the data transfer will be. Learn about TCP and UDP, and focus specifically on TCP windowing, sequence numbers, and acknowledgements.
Basic TCP/IP: Understanding Port Numbers
Imagine that you wanted to see your friend, Dave, who lived in a house with 100 other people. As soon as you reached the house, you would open the door and yell, “I’M LOOKING FOR DAVE!!!” Port numbers do exactly the same thing for network communication between devices, allowing you to dictate what service you are trying to reach.
LANs: Welcome to Ethernet
Ethernet defines the standard for LAN communication around the world. Because of this, it is critical to understand the fundamentals of how this “fabric of networks” operates. Learn about the origins of the Ethernet standard, CSMA/CD (the rules of communication), and the architecture of a MAC address.
LANs: Understanding the Physical Connections
Learn about the physical standards of Ethernet: UTP and Fiber Optics, straight-through vs. crossover cables, and an end-to-end picture of cabling in a corporate environment.
LANs: Understanding LAN Switches
Ethernet’s use of CSMA/CD allowed it to obtain much faster speeds than its competitor (token ring); however, it also led to many problems with collisions in larger networks. Learn about solutions to those problems and lay the foundation of understanding how the network switch fits into our network environments.
LANs: Working with the Cisco Switch IOS
Before you can jump right into setting up Cisco switches, you must understand how to work with Cisco’s operating system: the IOS.
LANs: Configuring Switch Security
Network security has become such a major topic that Cisco has moved much of what used to be considered a CCSP (security professional) topic into the CCENT and CCNA certifications. This section discusses the initial security of your switch, primarily focusing on configuring passwords, logon banners, and SSH.
LANs: Optimizing and Troubleshooting Switches
It’s time to wrap up the world of LAN switching with optimization and troubleshooting. In this chapter you will learn common problems you may encounter when working in a LAN environment.
Wireless: Understanding Wireless Networking
Wireless networking technology has changed the LAN landscape very quickly. As one of the newest technologies added to the CCENT/CCNA certifications, wireless is almost guaranteed to pop up in organizations of any size.
Wireless: Wireless Security and Implementation
Understanding the foundations of wireless is never enough! Security vulnerabilities have proven more than once that wireless can be devastating to an organization.
Advanced TCP/IP: Working with Binary
You will need to learn the skill of IP subnetting. One of the most foundational skills in subnetting is converting from decimal to binary and back. An excellent website to practice IP Subnetting is BootMask.
Routing: Initial Router Configuration
Routers are the device that made Cisco famous (as a Company). Unlike a switch, when you initially pull a Cisco router out of the box, it is non-operational; that is, you must initially configure the router before it works properly.
Routing: SDM, CCP, and DHCP Server Configuration
For the first time in Cisco certification history, a graphic user interface (GUI) is now used to configure Cisco devices. It’s known as the Cisco Security Device Manager, or SDM for short. Another option is Cisco Configuration Professional.
Routing: Implementing Static Routing
Once the router is initially configured with IP addresses and passwords, it will effectively…well, sit there. The router has IP addresses, but it is not routing yet.
Routing: Implementing Dynamic Routing with RIP
Static routing is great if you are paid by the hour, but dynamic routing works much better when you want to get the job done fast. The RIP routing protocol has definitely been around for quite some time and has proven itself as a stable routing protocol for small network environments.
Routing: Internet Access with NAT and PAT
Because nearly every organization uses a private IP addressing scheme, routing can occur within the company network, but fails when attempting to access the Internet. That’s where Network Address Translation (NAT) comes in to save the day.
Routing: WAN Connectivity
In addition to providing access between networks, routers also allow us to connect to the Wide Area Network (WAN).
Management and Security: Telnet, SSH, and CDP
At this point, we’ve wrapped up router-specific discussion and can now move into management and security strategies for all Cisco devices. The key management protocols we use to configure and monitor our devices are Telnet and SSH.
Management and Security: File Management
Having the ability to copy files to and from your routers and switches is key to successfully being able to back up configurations and IOS versions.
Whoa. Is that enough information for you yet?! This is just the tip of the iceberg in your quest to learn cisco networking! If you made it this far and you are still super excited and curious, well then, I wish you the best of luck and success in your Cisco Studies! If your eyes began to glaze over long before you reached this section of the article, then friend, IOS Networking may not be in your future.
In later posts, we’ll expand to ICND2, Security, CCNA tracks, and one of my favorites, GNS3 Lab Emulation Software and Cisco Packet Tracer Simulation software. With these tools, you can get the ‘Hands On’ skills you need with the switches and routers without having to go and buy yourself thousands of dollars of routers and switches to learn on.