See why networks are described in layers and how each layer adds its own job to a message. You will trace one request from an app down to the wire and back again.

Follow the major changes that shaped today’s protocols, from early packet switching and Ethernet to TCP/IP, the web, mobile networks, cloud networks, and encrypted-by-default traffic.

Set up a safe beginner lab using a laptop, terminal commands, Wireshark, packet captures, and small virtual networks. You will practice reading real traffic instead of only memorizing diagrams.

Cover the physical realities behind every protocol: signals, cables, fiber, radio, speed, distance, noise, duplex, and error rates. This gives you the judgment to tell protocol problems from media problems.

Work with Ethernet frames, MAC addresses, switches, broadcast traffic, and frame checks. You will see how local networks move data before IP ever gets involved.

Handle Wi‑Fi as a shared radio network with channels, authentication, roaming, interference, and frame behavior. You will connect wireless symptoms to the protocol choices that cause them.

Use switching tables, VLAN tags, trunks, and access ports to divide one physical network into safer logical networks. You will also see why loops are dangerous and how spanning tree prevents them.

Read IPv4 addresses, private ranges, public ranges, CIDR prefixes, and subnets. You will calculate usable addresses and design small address plans with confidence.

Move beyond IPv4 with IPv6 address types, prefixes, interface identifiers, router advertisements, and neighbor discovery. You will see how IPv6 changes local discovery, routing, and address planning.

Connect IP addresses to local delivery with ARP in IPv4 and Neighbor Discovery in IPv6. You will recognize common failures such as duplicate addresses, stale caches, and gateway confusion.

Trace how routers forward packets using destination addresses, next hops, routing tables, TTL or hop limit, and default routes. You will predict where a packet goes and why it might be dropped.

Use ICMP and ICMPv6 for errors, reachability, path discovery, and diagnostics. You will make sense of ping, traceroute, packet-too-big messages, and unreachable responses.

Work with UDP as a small, fast transport protocol for queries, streams, games, voice, telemetry, and tunneling. You will see what applications must handle when the transport does not guarantee delivery.

Follow TCP connections through handshakes, sequence numbers, acknowledgments, retransmissions, flow control, and connection close. You will read a TCP capture and identify normal behavior versus loss or reset problems.

See how networks share capacity with TCP congestion control, queuing, buffering, packet loss, latency, and jitter. You will connect performance complaints to real protocol behavior.

Use DNS as the Internet’s naming system: records, resolvers, authoritative servers, caching, zones, reverse lookups, and DNSSEC. You will diagnose common name resolution failures and bad records.

Handle automatic host setup with DHCP for IPv4 and the main options for IPv6. You will see how clients receive addresses, gateways, DNS settings, leases, and reservations.

Study NAT, port address translation, carrier-grade NAT, port forwarding, and the ways applications cope with private networks. You will see why NAT helps address shortages but complicates peer-to-peer traffic and troubleshooting.

Use TLS, certificates, public keys, certificate authorities, SNI, ALPN, and TLS 1.3 to explain how modern connections are protected. You will inspect a secure connection without treating encryption as magic.

Follow HTTP from requests and responses to headers, cookies, caching, proxies, status codes, HTTP/2 multiplexing, and API traffic. You will read web traffic and connect browser behavior to protocol details.

Give QUIC and HTTP/3 their own treatment: UDP-based transport, built-in encryption, stream multiplexing, faster connection setup, connection migration, and operational tradeoffs. You will know when QUIC helps and what it changes for firewalls and monitoring.

Cover the core protocols behind email delivery and access: SMTP, submission, IMAP, POP3, STARTTLS, SPF, DKIM, and DMARC. You will trace a message from sender to inbox and diagnose common delivery failures.

Work with VPN and tunneling protocols such as IPsec, WireGuard, GRE, L2TP, and SSL VPNs. You will compare site-to-site, remote-access, and overlay designs and spot routing or MTU problems inside tunnels.

Use access control lists, stateful firewalls, proxy behavior, intrusion prevention, and segmentation to control network conversations. You will write and test rules without accidentally blocking the traffic a service needs.

Study secure management protocols and weak legacy ones: SSH, SNMPv3, HTTPS management, NETCONF, RESTCONF, RADIUS, TACACS+, Telnet, and old SNMP communities. You will choose safer ways to manage devices and accounts.

Move from static routes to dynamic routing with route selection, metrics, administrative distance, convergence, and failure recovery. You will see why routing protocols exist before configuring any one of them.

Use OSPF and IS-IS concepts for internal routing: areas, neighbors, link-state databases, cost, shortest paths, and summarization. You will diagnose neighbor and route-advertisement problems in an enterprise-style network.

Study BGP as the protocol that connects networks across the Internet: autonomous systems, peering, prefixes, path attributes, policy, route leaks, filtering, and RPKI. You will see why business decisions and security shape global routing.

Handle traffic that needs special treatment with QoS, DSCP markings, policing, shaping, priority queues, and congestion management. You will design practical policies for voice, video, control traffic, and bulk transfers.

Cover multicast groups, IGMP, MLD, PIM, and common streaming or discovery uses. You will know when multicast is useful, when it causes surprises, and how to contain it.

Use NTP and PTP to keep systems aligned in time. You will see why accurate time matters for logs, certificates, security investigations, databases, voice systems, and industrial networks.

Apply cloud networking ideas without losing protocol detail: virtual networks, subnets, route tables, security groups, load balancers, private links, DNS zones, gateways, and hybrid connections. You will map familiar networking concepts onto cloud designs.

Cover container networking with namespaces, bridges, overlays, service discovery, ingress, network policies, and Kubernetes Services. You will trace traffic from a user to a pod and back across a cluster.

Study service mesh patterns such as sidecar proxies, mutual TLS, traffic splitting, retries, circuit breaking, and identity-based policy. You will see how application teams manage east-west traffic at scale.

Use SDN ideas such as control planes, data planes, overlays, programmable switches, and centralized policy. You will connect these ideas to data centers, cloud platforms, campus networks, and network virtualization.

Automate network work with templates, APIs, source control, validation, and infrastructure as code. You will build repeatable changes instead of relying on one-off command-line edits.

Observe networks with logs, packet captures, flow records, SNMP, streaming telemetry, synthetic checks, and eBPF-based visibility. You will choose the right evidence for outages, slowdowns, and security questions.

Work through a complete troubleshooting case from user report to scope, hypotheses, captures, device checks, fix, validation, and notes. You will practice a calm method that prevents guessing and blame.

Design a small but realistic network from requirements through address plans, VLANs, routing, DNS, DHCP, security rules, monitoring, documentation, and handoff. This ties the protocols together into decisions a practitioner must defend.

Cover the safety, privacy, and responsibility issues that come with packet access, encryption, logging, scanning, change control, outage risk, and incident evidence. You will know how to work carefully in real environments.

Plan your next steps in networking through roles such as support technician, network administrator, cloud network engineer, security engineer, SRE, and network architect. You will choose portfolio labs, certifications, communities, and reading habits that keep your protocol knowledge current.