Computer Networks

You can identify network topologies, categorize local and wide-area networks, and explain the fundamental client-server interactions that power distributed internet architecture.

1. What a network is and why it matters90 min
   • Packet switching
   • Bandwidth vs latency
   • Network nodes
   • End systems
2. Types of networks: LAN, WAN, MAN90 min
   • Local Area Networks
   • Wide Area Networks
   • Metropolitan Area Networks
   • Campus networks
3. Network topologies90 min
   • Star topology
   • Mesh topology
   • Bus and ring designs
   • Redundancy and fault tolerance
4. Clients, servers and peer-to-peer90 min
   • Client-server model
   • Peer-to-peer networks
   • Request-response cycles
   • Resource allocation
5. How the internet is structured90 min
   • Tier 1 ISPs
   • Internet Exchange Points (IXPs)
   • Autonomous Systems
   • Routing peering relationships

Hands-on project: Map out and document a physical and logical topology diagram for a multi-floor office building using correct LAN, WAN, and MAN components with redundancy checks.

You can trace how data encapsulates and decapsulates across both the seven-layer OSI model and the practical four-layer TCP/IP stack.

1. The seven layers of OSI90 min
   • Physical layer
   • Data Link layer
   • Network and Transport layers
   • Session, Presentation, and Application layers
2. The TCP/IP model90 min
   • Link layer
   • Internet layer
   • Transport layer
   • Application layer
3. Encapsulation and data flow90 min
   • PDUs (Protocol Data Units)
   • Header appending
   • De-encapsulation at the receiver
   • Payload transmission
4. Comparing the two models90 min
   • Theoretical vs practical models
   • Layer mapping differences
   • Industry standard adoption
5. Where protocols fit90 min
   • Protocol stack assignment
   • Layer interdependence
   • Modular design benefits

Hands-on project: Trace a packet capture walkthrough to map protocol headers to their corresponding OSI layers for an HTTP GET request.

You can configure Ethernet framing, identify MAC address tables on switches, and manage physical media constraints in local networks.

1. Transmission media and signals90 min
   • UTP copper cabling
   • Fiber optics
   • Signal attenuation
   • Electromagnetic interference
2. MAC addresses90 min
   • OUI (Organizationally Unique Identifier)
   • EUI-48 format
   • Broadcast addresses
   • MAC address spoofing concepts
3. Ethernet and framing90 min
   • IEEE 802.3 standard
   • Ethernet II framing
   • FCS (Frame Check Sequence)
   • CSMA/CD mechanics
4. Switches and switching90 min
   • CAM tables
   • Collision domains
   • Broadcast domains
   • Store-and-forward switching
5. Error detection basics90 min
   • CRC (Cyclic Redundancy Check)
   • Frame drops
   • Bit error rates
   • Link recovery

Hands-on project: Analyze Ethernet frames and switch forwarding tables using Cisco Packet Tracer to observe MAC learning behavior.

You can calculate custom subnets using CIDR notation, differentiate IPv4 and IPv6 schemas, and configure static routes on enterprise routers.

1. IPv4 and IPv6 addressing90 min
   • IPv4 32-bit structure
   • IPv6 128-bit hexadecimal format
   • Loopback addresses
   • Anycast and multicast
2. Subnetting and CIDR90 min
   • Subnet masks
   • CIDR notation (/24, /30)
   • Network and broadcast IDs
   • Host calculation formulas
3. Public versus private addresses90 min
   • RFC 1918 private address blocks
   • Public IP allocation
   • CGNAT (Carrier-Grade NAT)
   • Loopback and link-local ranges
4. Routers and how routing works90 min
   • Routing tables
   • Default gateways
   • Longest prefix match rule
   • Hop-by-hop forwarding
5. Routing protocols overview90 min
   • Distance vector vs link state
   • OSPF basics
   • RIP protocol
   • BGP high-level introduction

Hands-on project: Design a complete IPv4 addressing scheme with variable-length subnet masking (VLSM) and configure static routing across three connected routers.

You can analyze TCP connection states, implement reliable data transmission controls, and select the correct transport protocol for specific application requirements.

1. TCP versus UDP90 min
   • Connection-oriented vs connectionless
   • Reliability guarantees
   • Overhead comparison
   • Use case selection
2. Ports and sockets90 min
   • Well-known ports (0-1023)
   • Ephemeral ports
   • Socket pairs (IP and port)
   • Port binding
3. Reliability and the three-way handshake90 min
   • SYN, SYN-ACK, ACK
   • Sequence and acknowledgement numbers
   • Four-way termination
   • State machine transitions
4. Flow and congestion control90 min
   • Sliding window mechanism
   • Slow start algorithm
   • Congestion avoidance
   • Packet loss recovery
5. When to use each protocol90 min
   • Streaming media over UDP
   • Transactional reliability over TCP
   • Real-time gaming protocols

Hands-on project: Capture and inspect TCP three-way handshake packets using Wireshark to diagnose retransmissions and window scaling flags.

You can trace end-to-end web request lifecycles, configure DHCP scopes, and resolve domain name queries using standard DNS record types.

1. HTTP and HTTPS90 min
   • HTTP methods and status codes
   • Headers and payloads
   • TLS handshake encryption
   • HTTP/1.1 vs HTTP/2
2. DNS: how names resolve90 min
   • Root and TLD servers
   • Recursive vs authoritative resolvers
   • A, CNAME, MX, and TXT records
   • DNS caching and TTLs
3. DHCP and dynamic addressing90 min
   • DORA process (Discover, Offer, Request, Acknowledge)
   • Lease times
   • IP reservations
   • DHCP relay agents
4. FTP, SMTP and others90 min
   • FTP control and data channels
   • SMTP, IMAP, and POP3 for email
   • SSH and Telnet protocols
   • NTP for time synchronisation
5. How a web request travels end to end90 min
   • Browser cache check
   • DNS lookup sequence
   • TCP handshake and TLS negotiation
   • HTTP request dispatch

Hands-on project: Configure a local DNS and DHCP server environment, tracing a client machine acquiring an IP address and resolving an application hostname.

You can deploy wireless access points, configure Network Address Translation (NAT), and differentiate hardware routing and switching equipment.

1. Wi-Fi and wireless standards90 min
   • IEEE 802.11 standards (ac/ax/be)
   • 2.4 GHz vs 5 GHz vs 6 GHz bands
   • Channel overlapping
   • CSMA/CA mechanics
2. Access points and ranges90 min
   • BSSID and ESSID
   • Signal propagation
   • Roaming between access points
   • Dead zone mitigation
3. Routers, switches and hubs90 min
   • Layer 2 vs Layer 3 hardware
   • Hub collisions
   • Managed switch features
   • Router packet processing
4. NAT and port forwarding90 min
   • SNAT and DNAT
   • PAT (Port Address Translation)
   • Mapping internal services to public IPs
   • NAT traversal
5. Home and enterprise networks90 min
   • SOHO router setups
   • Enterprise structured cabling
   • Core, distribution, and access tiers

Hands-on project: Configure wireless security standards (WPA3) and setup NAT port forwarding on a gateway router in a simulated network lab.

You can configure basic firewall rules, implement secure shell access, and apply fundamental network hardening practices.

1. Common network threats90 min
   • Packet sniffing
   • IP spoofing
   • DDoS amplification attacks
   • Man-in-the-middle vectors
2. Firewalls and their role90 min
   • Stateless vs stateful inspection
   • Packet filtering rules
   • DMZ (Demilitarized Zone) design
   • Next-generation firewalls
3. Secure protocols: TLS, HTTPS, SSH90 min
   • Public key infrastructure basics
   • SSH key authentication
   • Cipher suite selection
   • Certificate authorities
4. VPN basics90 min
   • Site-to-site VPNs
   • Remote access VPNs
   • IPsec and WireGuard protocols
   • Tunnel encapsulation
5. Good security practices90 min
   • Principle of least privilege
   • Network segmentation
   • Port hardening
   • Regular firmware updates

Hands-on project: Write and apply iptables or hardware firewall rules to block unauthorized inbound traffic while permitting established web connections.

You can diagnose connectivity faults using standard CLI commands and capture packet dumps to isolate network bottlenecks.

1. Essential networking commands90 min
   • ipconfig and ifconfig
   • netstat and ss
   • arp table inspection
   • route print
2. ping, traceroute and nslookup90 min
   • ICMP echo request and reply
   • TTL expiration tracing
   • DNS query debugging with nslookup
   • Packet loss measurement
3. Reading IP configurations90 min
   • Subnet mask verification
   • Default gateway validation
   • DNS server assignments
   • DHCP lease status
4. Capturing traffic with Wireshark90 min
   • Promiscuous mode
   • Display and capture filters
   • Stream following
   • Analyzing handshake anomalies
5. A methodical troubleshooting approach90 min
   • Bottom-up vs top-down debugging
   • Isolating failure domains
   • Log analysis
   • Documenting incident root causes

Hands-on project: Execute a methodical troubleshooting runbook to identify and resolve simulated DNS lookup and routing loop failures on a live host.

You can configure and reason about dynamic routing and a loop-free switched topology.

1. Static routing and the routing table90 min
   • Longest-prefix match
   • Administrative distance
   • ip route and show ip route
2. OSPF as a link-state protocol90 min
   • Areas and the LSDB
   • DR and BDR election
   • Cost and convergence
3. BGP and inter-domain routing90 min
   • Autonomous systems
   • eBGP vs iBGP
   • AS-path and route selection
4. VLANs, trunking and spanning tree90 min
   • 802.1Q tagging
   • STP and RSTP
   • Root bridge election

Hands-on project: Build a three-router topology in GNS3 or Packet Tracer running OSPF with two areas, add a BGP peering to a simulated ISP, and demonstrate convergence time after failing a link.

You can configure devices from code and monitor a network instead of logging into boxes.

1. Why CLI-by-hand does not scale90 min
   • Config drift
   • Change auditability
   • Intent vs running state
2. Automating with Python and Netmiko90 min
   • send_config_set
   • Parsing show output
   • Idempotent checks
3. Ansible for network devices90 min
   • Inventory and groups
   • ios_config and nxos modules
   • check_mode dry runs
4. Monitoring, SNMP and flow data90 min
   • SNMP counters
   • NetFlow and sFlow
   • Syslog and alert thresholds

Hands-on project: Write an Ansible playbook that pushes a VLAN and an ACL to three devices idempotently, verify with a Netmiko script that diffs running config against intent, and chart interface errors in Grafana.

You can design addressing and connectivity for a cloud VPC and explain how traffic reaches it.

1. VPC addressing and subnet design90 min
   • CIDR planning
   • Public vs private subnets
   • Route tables
2. Connecting networks together90 min
   • VPC peering
   • Site-to-site VPN
   • Transit gateway and Direct Connect
3. Load balancing and DNS at scale90 min
   • L4 vs L7 balancing
   • Health checks
   • Anycast and GeoDNS
4. CDN, TLS and the modern edge90 min
   • Edge caching
   • TLS termination
   • HTTP/3 and QUIC

Hands-on project: Design and build a VPC with public and private subnets across two availability zones, add a NAT gateway and an application load balancer, peer it to a second VPC with non-overlapping CIDRs, and document the full path of an inbound request.

You can synthesize all core networking concepts to architect, simulate, and document an enterprise-grade network infrastructure from scratch.

1. Plan a network for a scenario90 min
   • Requirements gathering
   • Capacity and bandwidth planning
   • Site layout analysis
   • Redundancy design
2. Design the addressing and subnets90 min
   • VLSM allocation strategy
   • VLAN segmentation plan
   • IP assignment tables
   • Gateway allocation
3. Configure routing in a simulator90 min
   • Router interface setup
   • Static and dynamic route implementation
   • Switch trunking and access ports
   • End-to-end verification
4. Document and present the design90 min
   • Network architecture diagramming
   • Addressing documentation
   • Test case reporting
   • Design defense presentation
5. Portfolio, resume, mock interviews and career prep90 min
   • Networking resume positioning
   • Technical interview Q&A practice
   • Portfolio project packaging
   • Career path mapping

Hands-on project: Design, simulate, and document a complete multi-subnet enterprise network with redundant routing, security firewalls, and address allocation tables for your professional portfolio.