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Cisco

Systems · Taught with Cisco

Networking

Addressing, switching, routing and troubleshooting. You subnet a network by hand, build a campus in simulation, and diagnose faults by reading what the wire is telling you.

Download the course plan
  • Foundational
  • 5 phases
  • 23 sessions
  • First session free

Syllabus

5 phases · 23 sessions · each phase ends in something you have built

1

Read the Wire

Watch real traffic and learn which layer a problem lives on before touching a device.

$58

this phase

  1. 1.1

    How a Message Actually Travels

    Free preview

    Encapsulation, the TCP/IP model, and mapping OSI layers onto something you can point at.

    Open
  2. 1.2

    Ethernet, MAC, and ARP

    Frames, switch MAC learning, broadcast domains, and what ARP is really asking.

  3. 1.3

    IP, TCP, UDP, and Ports

    Addresses versus ports, the three-way handshake, and why UDP is not broken.

  4. 1.4

    Wireshark on Your Own Traffic

    Capture filters, following a stream, and watching DHCP, DNS, and TCP set up a single page load.

By the end of this phase:A packet capture of one page load, annotated frame by frame from DHCP request to first HTTP response.
2

The Addressing Wall

Do subnet math reliably, in binary, without a calculator and without a lookup chart.

$58

this phase

  1. 2.1

    Binary, Bit by Bit

    Powers of two, dotted decimal to binary and back, and reading a mask as a boundary.

  2. 2.2

    Subnetting Without a Chart

    Splitting a block, network and broadcast addresses, usable host ranges, and drills every session from here on.

  3. 2.3

    VLSM and Summarization

    Sizing each subnet to its actual host count, then summarizing the result back up into one route.

  4. 2.4

    IPv6 Addressing

    Hex, the /64 convention, link-local versus global unicast, SLAAC, and running dual stack alongside IPv4.

  5. 2.5

    The Same Plan in a Cloud VPC

    Applying your CIDR plan to an AWS VPC: subnets, route tables, and security groups on the same math.

By the end of this phase:A VLSM addressing plan for a four-site organization, IPv4 and IPv6, written on paper and then built once as a cloud VPC.
3

Build the Campus

Configure a switched network on Cisco gear and predict what it will do before you press enter.

$58

this phase

  1. 3.1

    Living in Cisco IOS

    Modes, show commands, SSH access, and saving a config so a reload does not erase your evening.

  2. 3.2

    VLANs and Trunks

    Access ports, 802.1Q tags, the native VLAN, and segmenting a campus that still needs to talk.

  3. 3.3

    Inter-VLAN Routing

    Router-on-a-stick versus switched virtual interfaces, and choosing one on purpose.

  4. 3.4

    Redundancy That Holds

    STP and RSTP root election, PortFast, BPDU guard, root guard, and EtherChannel bundles.

  5. 3.5

    Wireless and PoE

    Controller-based WLAN architecture, SSIDs, WPA3, and powering access points over the same cable.

By the end of this phase:A multi-VLAN campus LAN, wired and wireless, with every device config committed to Git.
4

Route, Serve, and Defend

Connect the sites, hand out addresses, reach the internet, and refuse the traffic that should not pass.

$58

this phase

  1. 4.1

    Static Routing and the Routing Table

    Next hops, longest-prefix match, default routes, and reading a routing table out loud.

  2. 4.2

    OSPFv2, Single Area

    Neighbors, adjacency, cost, and watching a network reconverge after you unplug a link.

  3. 4.3

    IP Services: DHCP, NAT, NTP, Syslog

    Address pools, translating private to public, and timestamps that make two logs comparable.

  4. 4.4

    First-Hop Redundancy and Dual Stack

    HSRP, a default gateway that survives a dead router, and routing IPv6 next to IPv4.

  5. 4.5

    Access Control and Port Security

    Standard and extended ACLs, where to place them, port security, and a hardened default config.

By the end of this phase:A routed multi-site internetwork running single-area OSPF with DHCP, NAT, and ACLs, tested against a written spec.
5

Break It, Then Automate It

Diagnose a network you did not build, then stop fixing the same thing by hand.

$58

this phase

  1. 5.1

    A Method, Not a Guess

    Symptom to layer to hypothesis to test, and the show commands that settle each question.

  2. 5.2

    Broken Network Clinic

    Working labs sabotaged one fault at a time, on the clock, writing down what you ruled out and why.

  3. 5.3

    Devices Have APIs

    JSON, REST calls against a controller, and a first Python script that pulls config off a switch with Netmiko.

  4. 5.4

    Ansible, and AI in the NOC

    Playbooks instead of copy-paste, config as reviewable text, and where an AI assistant helps or quietly lies.

By the end of this phase:A triage logbook covering eight injected faults, plus an Ansible playbook that builds the lab from an empty config.

Tools you will use

  • Cisco Packet Tracer
  • Cisco IOS CLI
  • Cisco Modeling Labs (CML-Free)
  • Wireshark
  • Cisco NetAcad
  • Python + Netmiko
  • Ansible
  • AWS VPC

What you will build

  • The Addressing Plan

    Four sites, one block, IPv4 and IPv6

  • Campus Build-Out

    VLANs, wireless, and OSPF against a written spec

  • Eight Faults

    Diagnose a network you did not build