Lessons

  1. The world of networks - Introduction Communication has evolved greatly. Traditional communication methods such as mail have been overtaken by more sophisticated forms. Electronic Communication methods offer higher speeds; more efficiency, reliability, integrity, security; scale across larger geographical areas and require less resources to use. Tools and services such as e-mail, blogs, podcasts, instant messaging, and social networks among other […]
  2. TCP/IP and the OSI Model - Overview In the previous chapter we were introduced to computer networks and we got to know their importance in everyday lives. In this chapter, we will look at the layered models that are used in communication over networks. We will discuss the TCP/ip model and the OSI model to better understand how communication works. This […]
  3. Application layer - Overview As I am sure, most of you use the internet in a number of ways; be it browsing the web, downloading movies, financial transactions, blogging, IM messaging among others. We are most likely oblivious of what it is that makes this communication possible. In this chapter, we will look at the first layer of […]
  4. Transport layer - Overview In the previous chapter, we looked at the application layer and saw that it is the interface between the human network and the data network. In this chapter, we will look at the transport layer and discuss how it aids in communication. At the end of this chapter, you should be able to describe […]
  5. Network layer - Overview In the previous chapter, we looked at the role of the OSI transport layer in communication. In this chapter, we will look at the network layer. We will discuss the addressing used, the functions, and the different network layer protocols, introduce IPv4, understand how packets move in the network and finally give an overview […]
  6. Addressing in ipv4 – part 1 - Overview In the previous chapter, we looked at the network layer and its involvement in communication. in this chapter, we will look at ipv4 addressing. This is one of the most important concepts in networking and will be critical in your overall success in networking. Understanding this chapter is critical to the rest of your […]
  7. Addressing in ipv4 – part 2 - Welcome to part 2 of addressing in ipv4. In part 1 we looked at how IP addresses are assigned in ipv4. We looked at the various types of ipv4 addresses and we also did basic subnetting. In part 2, we will continue subnetting and introduce a few more concepts. Classful addressing in ipv4 When IPv4 […]
  8. Data link layer, Ethernet and physical layer - Overview In the previous chapters, we learnt about the application layer and transport layer port communication, we also looked at the network layer and IPv4 addressing for remote delivery of packets. In this chapter we look at the data link layer and discuss how it prepares packets for transport over different types of media and […]
  9. Planning and cabling the network - Overview In our previous chapters, we have looked at the OSI and TCP/IP models in detail and explained how they aid in communication. All these concepts lead up to this chapter and beyond. In this chapter, we will learn how to plan our networks and look at the various cabling options to use in our […]
  10. Configuring and testing the network - Overview In this chapter, we will learn how to configure the various internetwork devices such as the router and the switch. We will also cable the network correctly according to the requirements and learn the various CISCO IOS – CISCO internetwork operating system basics that we will use throughout the course. As we mentioned in […]
  11. Static routing - Overview Welcome to the world of routing. In the next few chapters, we will look at how packets find their way in networks through routers. In this chapter, we will learn static routing. Routers in our networks discover remote networks in one of two ways; Statically configured routes Dynamic routing protocols We will learn various […]
  12. Dynamic routing protocols - Overview In the previous chapter, we looked at static routing. We saw how the router finds the best path to a network. We configured static routes and traffic was able to flow between two points. In this chapter, we will give an overview of dynamic routing protocols. We will define them and learn how they […]
  13. EIGRP part 1 - Overview Welcome to the world of EIGRP. In this chapter, we will look at CISCO’s proprietary routing protocol which is EIGRP. In part 1, we will look at the foundation concepts into distance vector routing protocols operation. We will then look at the EIGRP concepts and get to know how it works as well as […]
  14. EIGRP part II - Overview In part 1 of EIGRP, we explored some of the EIGRP concepts, we saw how it works and how routes are learnt, we also looked at the tables in EIGRP as well as the algorithm used and the different packet types. We also configured EIGRP and verified operation using the various show commands. in […]
  15. OSPF Part I - Overview Welcome to the world of OSPF (Open Shortest Path First) routing. This protocol was developed to replace RIP and it is a classless Link State routing protocol that uses areas so as to scale better. This chapter is divided into four parts since it is too broad. The concepts we will learn will be […]
  16. OSPF Part II - Overview In the first part, we took a look at link state routing protocols and discussed how OSPF works. We also learnt how to configure OSPF. In part two of this chapter on OSPF, we will look at more concepts such as the OSPF metric, suppression of OSPF updates and redistributing the default route. OSPF […]
  17. OSPF Part III - Overview In part 1 and part 2 of this chapter, we looked at the concepts behind OSPF operation. In part three and the last part, which is part four, we will look at more advanced concepts in OSPF. In part three we will look at multi area OSPF. We will learn how it is different […]
  18. OSPF Part IV - Overview In part 1 and part 2 of this chapter, we looked at the basic configuration of OSPF and further learnt more OSPF concepts such as redistributing the static routes and the metric, in part three, we looked at multi-area OSPF. In part four, we will look at OSPF and multi-access networks, we will conclude […]
  19. Introduction to LAN switching - Welcome to the world of LANS, in the previous couple of chapters, we learnt about routers and how they are used in the networking environments. In the next couple of chapters, we will learn about LANs and the main device we will use will be the SWITCH. The concepts we will learn will also tie […]
  20. Switch Concepts and Configuration Part I - Overview In this chapter, we will explore switching concepts and the basic configuration of a switch. We will discuss the switch’s operation, layer 2 and layer 3 switching as well as other concepts. We will conclude with the basic configuration of a switch and this will lead us into the discussion on VLANs. CSMA/CD We […]
  21. Switch Concepts and Configuration Part II - Overview In the previous part, we looked at some of the concepts behind switch operation. In this chapter, we will continue with the configuration and verification of the basic switch configuration, configure and verify port security on a switch and learn some other important concepts. Duplex settings As we mentioned in part 1 of this […]
  22. VLANs Part I - Overview In the previous chapter, we looked at the various concepts that make switches work. In this chapter, we will look at VLANs. We will discuss what they are, how they work and advantages of using VLANs in our LAN networks. We will also configure VLANs in our LAN networks. What are VLANs VLANs (Virtual […]
  23. VLANs Part II - Overview In part one of this chapter, we learnt how to configure VLANs on a switch. In this section, we will focus on deleting of VLANs on a switch, verification of configured VLANs as well as troubleshooting of some common VLAN problems. Deleting VLANs In other chapters, we have seen that using “no” at the […]
  24. STP Part I - Overview In the previous chapter, we looked at how we can segment a network using VLANs. In this chapter, we will discuss redundancy and how the end devices in the switched network are able to recover from a failure. We will discuss the role of STP in making sure that there are no loops as […]
  25. STP Part II - Overview In part 1 of this topic on STP, we looked at the STP concepts and discussed how STP helps in redundancy and loop prevention in LAN networks, in this second part, we will configure STP and as well as troubleshoot STP. Configuration of STP By default STP is on by default on CISCO switches, […]
  26. Ether channel - Overview in the previous chapter, we looked at the role of redundancy in the network and the prevention of loops in redundant LANs using STP. In this chapter, we will look at how we can utilize the links between our switches more effectively even in a network that STP has blocked links on. We will […]
  27. STP Part III - Overview In part 1 and 2 of this chapter, we focused on 802.1D STP, in this chapter, we continue with STP but we will focus on the different variations of STP mainly; PVSTP and RSTP. We will begin with the concepts that make these protocols different from 802.1D STP, then we will configure PVSTP and […]
  28. Inter-VLAN Routing - Introduction In previous chapters, we learnt how VLANs segment broadcast traffic on a switch and segment a switched network into different LANs, we also learnt how VLAN information can be transmitted to other switches in the network using VTP and how we can avoid layer two loops using STP. Consider, this, as the network administrator, […]
  29. Introduction to WANs - Introduction In the previous chapters, we have been primarily focused on LAN technologies, however, as an enterprise grows, so does its networking needs. Consider company ABC, they formed in 2010 in New York, however, over the last couple of years they have grown rapidly and they now have three branches, one in Los Angeles, Miami […]
  30. Serial Connections and HDLC - Introduction In the last chapter, we discussed some of the concepts that make the WAN work, we briefly described some of the protocols in the WAN. In this chapter, we will discuss serial links and the physical connections we use. We will then explore the default encapsulation on CISCO routers which is HDLC and finally […]
  31. PPP (Point-to-Point Protocol) - Introduction In the previous chapter, we discussed serial connections in the WAN, we also discussed the default data link encapsulation on CISCO switches which is HDLC. In this chapter, we will look at PPP, we will discuss some of its concepts, learn how to configure PPP as well as its authentication options and finally we […]
  32. Frame Relay Part I - Overview In the previous chapter, we looked at PPP, we discussed how PPP worked and we said that it works at the data link layer, in this chapter, we will look at the final WAN topic in this course which is frame relay. In part 1, we will discuss the concepts behind frame relay operation […]
  33. Frame Relay – Part II - Overview In part one of this chapter, we looked at the concepts behind frame relay operation. We discussed the role of the PVC’s, DLCI mapping, inverse ARP among other topics. In part two of this chapter, we will discuss more advanced frame relay concepts and finally look at the commands used to troubleshoot frame relay. […]
  34. Network Security - Overview In the last chapter, we looked at frame relay and discussed its importance in the WAN. In this chapter, we will look at some network security concepts that are vital in today’s world. We will look at some of the risks as well as the ways we can secure our devices, we will also […]
  35. ACLs (Access Control Lists) Part I - Overview In the last chapter, we discussed network security and saw its importance in our networks. In this chapter, we will delve into the world of ACLs, in part 1, we will look at the ACL concepts as well as configuring standard ACLs. In part 2 of this chapter, we will continue with configuration but […]
  36. ACLs – Part II - Overview In part one of this chapter, we looked at the ACL concepts, we discussed how they worked and we topped it off with configuration of standard ACLs. In part 2, we will discuss extended ACLs and other ACL concepts, we will then configure extended ACLs and finish off with troubleshooting ACLs. Extended ACLs With […]
  37. DHCP (Dynamic Host Configuration Protocol) - Overview Ip addressing is a very important job network administrators have to accomplish, configuring ip addresses on routers, and other devices can be a challenge especially when the number of devices is many. In this chapter, we will discuss a solution to ip addressing of hosts which is DHCP. We will look at the concepts […]
  38. NAT (Network Address Translation) - Overview In the previous chapter, we saw how DHCP is useful in assigning ip addresses to hosts in a network. In this chapter, we will look at another important ip service that helps hosts access the internet. We will learn about, NAT operation and IPv4, and configure and troubleshoot NAT. NAT in today’s networks In […]
  39. IP Services - Overview In the previous chapter, we learnt how NAT is important in helping devices in a network access the internet, we also looked at DHCP and how it helps in automatic ip configuration on hosts as well as the use of ACLs in filtering traffic in our networks. In this chapter, we will look at […]
  40. IPv6 (Internet Protocol version 6) - Overview Ipv6 is one of the most emerging technologies in networks. IPv4 addresses are almost exhausted and as such there is need for a new and better solution. In this chapter on IPv6, which is the last chapter of this CCNA training course we will look at the concepts behind this protocol, we will learn […]