Interconnecting Cisco Networking Devices Pt. 2

ICND2 200-101

ICND2 200-101 Course & Exam

Our very first discussion in ICND2 is centered around scaling our layer 2 environment. To scale, we need to implement virtual LANs, or VLANs, and additional protocols, such as 802.1.q, which allows us to implement trunks. Now this discussion will be more of a review as a considerable amount of time was dedicated to this topic in ICND1. However, in addition of this review, we will identify the different ways VLANs and trunks can fail and how we can troubleshoot these situations. Be aware that when we scale our layer 2 environment by introducing more switches and more links to reduce those single points of failure, we create loops that can adversely affect the usability of the network. So we rely on a very important protocol known as Spanning Tree Protocol or STP for short, and a thorough understanding of it is required if we expect to manage and maintain a medium to large layer 2 environment.

Even if we have redundant links between our switches to increase bandwidth or provide a level of comfort if a link fails, Spanning Tree Protocol will disallow traffic to flow on one of those links because it sees it as a loop. So later on in ICND2 we will look at how we can override this behavior by using ether channel and ultimately allowing us to use both links at the same time while maximizing our bandwidth. We also have an introduction of first-hop redundancy protocols and why we should consider them when designing our default gateways within the organization.

The art of troubleshooting is where you earn your stripes. Being able to diagnose and resolve issues is an essential skill that all network engineers need to develop. So we will introduce you to a structured approach and some tools that should help you start earning your stripes. Remember, the best troubleshooters in the world are those that have been put in disastrous situations many times and have gained the experience and ultimately the stripes. So this is just a starting point, and we will focus on both IP version 4 and IP version 6.

The first dynamic routing protocol covered in ICND2 is Enhanced Interior Gateway Routing Protocol, or EIGRP. It was developed by Cisco for Cisco environments. Since this is the first time Cisco introduces you to it, you will learn the fundamentals, which include terminology, its metric, how it selects routes, and how to set it up and verify a basic EIGRP network for IP version 4. Since IP version 6 popularity has increased, we will also spend time identifying how EIGRP for IP version 6 differs from EIGRP for IP version 4 and how we can implement it in our IP version 6 environments. And let's not forget about earning our stripes. We will also discuss how we can troubleshoot both EIGRP for IP version 4 and IP version 6. The goal of this part is to recognize how to implement, configure, and troubleshoot EIGRP for IPv4 and IPv6.

Open Shortest Path First, or OSPF, should not be new to us as ICND1 spends a considerable amount of time introducing you to the fundamentals and basic configuration tasks of OSPF. In ICND2, we take OSPF a step higher. We now look at how we can scale our OSPF solution by breaking up the domain into multiple areas. We finally see how the routers play different roles in the hierarchy based on where they are. We even dive into the LSA that Link State Advertisement and the different types that can flow around the OSPF domain. So you need to take your time and really learn everything that is presented to you here, so you can truly become a master of OSPF. If you cut corners here, eventually those cut corners will come back and haunt you as you dive deeper into the scalability features of OSPF. Once when we know more about Open Shortest Path First, or OSPF, let’s learn how we can implement, verify, and troubleshoot a multi-area OSPF solution. On top of that, let’s not forget about OSPF version 3, which is the version of the OSPF we use in IP version 6 environments. We will look at the differences between OSPF version 3 for IP version 6 and OSPF version 2 for IP version 4, in addition to how we can implement and verify that OSPF version 3 solutions.

Most of us venture outside our local area networks on a regular basis. We visit the Internet and connect to remote local area networks that are thousands of miles away from us. How do we do that? The goal of this course is to explain WAN technologies, and configure and troubleshoot a serial connection. Well there are many different ways and we will spend some time introducing you to those different ways here. In addition to that introduction, we will dive deeper in the leased line WAN connections, and how we can physically connect the leased lines, and what layer 2 protocols we use to make that ultimate connection.

Leased line connections give us that dedicated connection from one site to another site, but at a rather high cost. They are expensive. So a more economical approach for many of us is to use a shared infrastructure through the WAN, such as Frame Relay. As we will see, Frame Relay is a proven, package-switching, connection-oriented technology that gives us the ability to connect our sites together over a shared layer 2 WAN infrastructure. We are still keeping our traffic separate. Take the time to learn the terms associated with Frame Relay here, especially the data-link connection identifier, or DLCI, as we take you on a trip to help you understand it better. We will also look at how we can implement, verify, and troubleshoot that frame relay infrastructure.

Network Management and maintenance is essential. You need to be armed with the right tools and protocols to ensure that your network devices are performing as they should and that the network is not being abused. You'll be introduced to Simple Network Management Protocol, or SNMP, and system configuration dialog, or syslog, which you can use to monitor your devices and NetFlow, which you can use to monitor the traffic flowing in and around your network. In addition, you have to be prepared for when a disaster strikes. So we will discuss how you can ensure that you have a remote copy of the operating systems and the configuration files that are used by your devices. And to wrap it all up, you'll have a look at the new structure that Cisco hasn't placed for licensing the Internetwork Operating System, or IOS.

In the end don't forget to test your skills and knowledge with our 200-101 ICND2 practice tests.