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Network Fundamentals

If you can understand the fundamental networking building blocks, you can understand everything else in the industry. That is the goal of the Networking Fundamentals course. The course is made up of three separate classes: Networking 101, 102, and 103.

Networking 101 dissects the subnetting process. We start at the very basic building blocks, learning some binary. Then the course move into counting and converting binary numbers. That knowledge is then applied to the process of subnetting, as we discuss the binary method of subnetting. After some practice, we then look at a subnetting shortcut that will make ‘on the fly’ subnetting much more convenient, accurate, and quick.

Networking 102 is all about exploring everything that happens to get a packet from here to there. We start with a very basic network set up of two PC’s directly connected to one another, and use that to visit ARP and how it works, as well as why it is needed. We then expand our topology and add a switch in the middle, which allows us to study switching behavior. And finally we add one and then two routers to explore the process of Routing.

Networking 103 dives a little further into OSI layers two, three, and four. We start out exploring the concept of VLANs, and discussing what they provide and how. Then we finish our discussion of VLANs with a look at a Layer 2 Ethernet header. We then look at the Internet Protocol (IP) and study a few of the built-in features of the Internet Protocol. After which we take a look at the IP header. Next, we dive into TCP and discuss its many features, as well as how they function. We then examine a TCP header and study TCP in live packet captures. Finally we analyze UDP, and study UDP traffic in Wireshark.

By the end of this class, the students will be able to:

  • Understand IP Addresses and Subneting
  • Understand the roles of each layer of the OSI Model
  • Understand and explain the functionality of hosts, switches, routers, and ARP
  • Fully comprehend what it takes for a Packet to travel across a network or networks
  • Understand VLANs and how they are used
  • Understand the L2, L3, and L4 headers (Ethernet, IP, TCP/UDP)
  • Understand MAC Addresses, IP Addresses, and TCP/UDP Port Numbers
  • Understand what TCP accomplishes and how it accomplishes it
  • Understand UDP, and the benefits it provides
No scheduled public classes.
Contact us to schedule a private delivery.
3 days / 24 hours
Delivery Format:
Physical Classroom
Virtual – Live delivery
Target Audience

Entry level Network Administrators / Engineers (CCNA~ level)


Non-Network Engineer roles. For example…:

  • Developers
  • Client/Server Support
  • Managers
  • Sales
  • Solution Architect
  • etc




Networking 101 – Subnetting 

  • Router Illustration
    • Why must IP addresses exist in groups?
    • Hierarchical IP design
    • Three attributes to configure for network connectivity
    • Parts of an IP Address: Network and Host
  • Counting in Binary
    • Rules for counting in Decimal
    • Applying those rules for counting in Binary
    • Binary practice
  • Converting Binary to Decimal
    • Makeup of a binary number
    • Process to convert Binary to Decimal
    • Conversion table: Binary to Decimal
    • Conversion table: Decimal to Binary
  • Subnetting (binary method)
    • Goal: Is the target IP in my network or not?
    • Network and Host portion of an IP Address
    • Limited Possibilities for Subnet Mask
    • Six things you can learn from an IP/Mask
      • Network ID
      • Broadcast IP
      • # of Addresses
      • First Host IP
      • Last Host IP
      • Next Subnet
    • Subnet masks are locally significant
    • CIDR
    • Converting between Subnetting and CIDR
  • Subnetting (easy method)
    • Subnetting “shortcut table”
    • Using the shortcut table for /1-/24

Networking 102 – Packet Traveling 

  • OSI Model
    • Seven layers of the OSI Model
    • Layer 1
    • Layer 2
    • Layer 3
    • End to End vs Hop to Hop
    • Layer 4
    • Layer 5-7
  • Key Players
    • Host / Client / Server
    • Switch
    • Router
    • ARP
  • Packet Traveling: Host to Host
    • What is needed for two hosts to speak?
    • ARP Process
    • Encapsulation
    • Exercise: Can HostA communication with HostB?
    • LAB N102-A – Wireshark, ipconfig, TCP/IP Services, Windows Firewall
    • LAB N102-B – Host to Host communication
  • Packet Traveling: Host to Switch to Host
    • How a switch forwards traffic
    • How a switch learns MAC addresses
    • Populating the MAC Address Table
    • Exercise A: Populate ARP and MAC Tables
    • Demonstration: Proving switch flooding behavior
    • Exercise B: Populate ARP and MAC Tables
    • Exercise C: Populate ARP and MAC Tables
    • LAB N102-C – Host to Switch to Host, Flooding and ARP
  • Packet Traveling: Host to Switch to Router to Switch to Host
    • How a router forwards traffic
    • Learning Routes from Directly Connected networks
    • Layer3 devices have ARP tables
    • All 30 steps for a ping to get from HostA to HostD through Switch/Router/Switch
    • Populating all relevant tables: ARP, MAC, Routing
    • LAB N102-D – Studying each step in a Packet Capture
  • Packet Traveling: Host to Switch to Router to Router to Switch to Host
    • What directly connected routes don’t tell you about
    • Static Route has three parts: NetID, Mask, Next-Hop IP
    • Static Route Examples
    • Static Route for all Networks (Default Route)
    • Exercise: Determining all required Static and Default Routes
    • Overlapping Routes
    • LAB N102-E – Static Routes on a host

Networking 103 – Exploring the most important OSI Layers

  • VLANs
    • Mini switches
    • Access Port / Trunk Port
    • VLAN Tagging
    • Layer 2 Frame
    • 802.1q
    • Exercise: Determining the path of path of Traffic
  • Internet Protocol
    • What is IPv4?
    • Time to Live
    • Traceroute
    • Fragmentation
    • IP Header
    • LAB N103-A – Analyzing a Traceroute in Wireshark
    • LAB N103-B – Creating and Analyzing Fragmented Packets
  • Transport Layer
    • L4 exists to segregate data streams
    • What is a Socket?
    • Destination Port is known
    • Source Port is random
    • What is a Connection?
    • Forward and Return traffic
    • TCP vs UDP
  • TCP
    • Sequence Numbers
    • Acknowledgement Numbers
    • Tracking Bytes
    • Retransmission
    • Delayed Acknowledgement
    • Window Size
    • Flow Control
    • TCP is bidirectional
    • Three Way Handshake
    • Tracking data transfer through a connection
    • Connection Closer: FINs and RSTs
    • TCP Header
    • LAB N103-C – Analyzing a TCP capture in Wireshark
    • LAB N103-D – Analyzing simple TCP services in Wireshark
  • UDP
    • UDP is not TCP
    • Benefits of UDP
    • UDP Header
    • Types of applications that use UDP
    • LAB N103-E – Analyzing UDP conversation
    • LAB N103-F – Capturing youtube traffic