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CCNA Library (74)
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Network (13)
Device Operations (5)
Network Access (12)
Wireless (6)
IP Connectivity (10)
IP Services (11)
Security (10)
Automation (7)
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CCNA 74 topics across all 7 categories

CCNA® 200-301

Cisco's foundational networking certification. Aligned to the official 200-301 exam blueprint. Each topic page: TL;DR · mental model · topology · commands · verification · common mistakes · lab · cheat strip.

Free: CCNA 12-Week Study Plan Week-by-week schedule · free certs to stack · lab list · mock-exam strategy Open →
Blueprint coverage

Mapped to the official Cisco 200-301 v1.1 blueprint.

Cisco's exam blueprint defines six weighted domains. Our library covers every one — these are the same buckets Cisco grades you on. The table below maps our categories to the official domains.

Official Cisco 200-301 domain Our library categories Topics
1.0 Network Fundamentals Network Fundamentals + Device Operations 13 + 5
2.0 Network Access Network Access + Wireless 12 + 6
3.0 IP Connectivity IP Connectivity 10
4.0 IP Services IP Services 11
5.0 Security Fundamentals Security Fundamentals 10
6.0 Automation & Programmability Automation & Programmability 7

Cisco®, CCNA® and 200-301 are trademarks of Cisco Systems, Inc. PacketMentor is independent and not affiliated with Cisco. Weights are from the official Cisco 200-301 v1.1 blueprint.

Network Fundamentals

13 topics
Network Fundamentals Foundational

OSI Model & TCP/IP

Two networking reference models compared side-by-side. The seven OSI layers, the four TCP/IP layers, and which one the real internet actually runs on (spoiler: not OSI).

#01 Open topic →
Network Fundamentals Foundational

IPv4 Addressing

32-bit addresses, dotted decimal, classful vs classless, private ranges, and the special addresses (loopback, broadcast, APIPA) you should never accidentally use for production hosts.

#03 Open topic →
Network Fundamentals Foundational

TCP vs UDP

Two flavors of Layer 4 transport. TCP gives reliability and order at the cost of latency; UDP gives speed with no safety net. Covers the 3-way handshake, ports, when to use each, and the protocols that pick the wrong one.

#04 Open topic →
Network Fundamentals Foundational

Subnetting

Definitive CCNA-level subnetting guide — magic-number method, VLSM, wildcard masks, enterprise IP plans, 8 worked practice problems, and the subnetting-at-the-speed-of-conversation drill.

#05 Open topic →
Network Fundamentals Foundational

IPv6 Basics

128-bit addresses, hex notation, the :: shortcut, address types (global, link-local, multicast), SLAAC, and why IPv6 is finally happening 25 years after it was supposed to.

#06 Open topic →
Network Fundamentals Foundational

ARP — Address Resolution Protocol

How a host turns an IP address into the MAC address it needs to actually deliver a frame. Broadcast question, unicast answer, cached for hours. Also covers Gratuitous ARP, Proxy ARP, and the ARP spoofing attack.

#07 Open topic →
Network Fundamentals Foundational

ICMP — Internet Control Message Protocol

The network's diagnostic channel. Covers echo / reply (ping), destination unreachable, TTL exceeded (traceroute), and the security trade-offs of blocking ICMP at the firewall.

#08 Open topic →
Network Fundamentals Foundational

TCP 3-Way Handshake

The three packets every TCP connection starts with — SYN, SYN-ACK, ACK. Covers sequence numbers, the half-open state, SYN floods, and why HTTPS connections feel slower than they should over high-latency links.

#09 Open topic →
Network Fundamentals Foundational

Cabling & Media Standards

What's actually inside the cables and fiber you're plugging in — Cat5e/6/6A/8, single-mode vs multi-mode fiber, transceivers (SFP/SFP+/QSFP), distance and bandwidth limits, when to use what.

#12 Open topic →
Network Fundamentals Intermediate

MTU & Fragmentation

Why packets get fragmented or dropped on links with smaller MTU than expected. Covers MTU vs MSS, the Don't-Fragment bit, ICMP 'Fragmentation Needed,' Path MTU Discovery, and why blocking ICMP breaks the internet.

#48 Open topic →
Network Fundamentals Foundational

WAN Connection Types

The connection types you'll actually meet at branch sites — leased lines, Metro Ethernet, MPLS L3VPN, broadband (cable / DSL / FTTH), wireless (LTE/5G), and how SD-WAN ties them together.

#63 Open topic →
Network Fundamentals Foundational

Hierarchical Network Design

Cisco's three-tier model — Access, Distribution, Core — and the design principles that have built every campus network for 25 years. When to collapse the core, where to put redundancy, and why hierarchical design beats flat networks every time.

#64 Open topic →
Network Fundamentals Foundational

Network Virtualization & Containers

Hypervisors, virtual machines, virtual switches, containers, container networking — how server virtualization changed networking and what a CCNA candidate must understand.

#81 Open topic →

Device Operations

5 topics

Network Access

12 topics
Network Access Foundational

MAC Address Table

How a switch learns where every device is and decides where to forward each frame. Covers source-MAC learning, destination-MAC lookup, unknown-unicast flooding, and the CAM table on Cisco switches.

#09 Open topic →
Network Access Foundational

VLANs

Definitive CCNA-level VLAN guide — broadcast domains, access vs trunk ports, 802.1Q tagging, native VLAN, voice VLANs, VTP, VLAN design, the 6-step trunk debug, security pitfalls, and 7 worked exam scenarios.

#10 Open topic →
Network Access Foundational

Trunks & 802.1Q Tagging

How switches carry multiple VLANs over a single link using 802.1Q tags. Includes DTP behavior, native VLAN gotchas, and the allowed-VLAN list.

#11 Open topic →
Network Access Foundational

Spanning Tree Protocol (STP)

Definitive CCNA-level STP guide — why loops are catastrophic, bridge ID + priority election, three port roles, five port states, BPDU anatomy, PortFast + BPDU Guard + Root Guard + Loop Guard, RSTP convergence, MSTP overview, and 8 worked scenarios.

#12 Open topic →
Network Access Intermediate

EtherChannel (Link Aggregation)

Bundle multiple physical links between two switches into one logical Port-Channel — more bandwidth, instant failover, and STP sees it as a single link. Covers LACP, PAgP, static, and load-balancing methods.

#13 Open topic →
Network Access Foundational

Switching Operation

How a switch actually decides where to forward each frame. Covers source-MAC learning, destination-MAC lookup, the three outcomes (forward / flood / drop), and store-and-forward vs cut-through.

#18 Open topic →
Network Access Foundational

CDP & LLDP — Neighbor Discovery

How devices learn about their directly-connected neighbors. CDP is Cisco-proprietary; LLDP is the vendor-neutral standard. Both shout the same info: who I am, what model, what IOS, what port — invaluable for troubleshooting.

#19 Open topic →
Network Access Intermediate

BPDU Guard & Root Guard

Two Spanning Tree security features that protect your STP topology from misconfiguration and rogue switches. BPDU Guard locks user-facing ports; Root Guard pins the root bridge so a misplaced switch can't hijack it.

#21 Open topic →
Network Access Foundational

Catalyst Boot Process

What happens between powering on a Cisco device and the prompt appearing. Covers POST, ROMMON, IOS image selection, config register, boot variables, and password recovery.

#22 Open topic →
Network Access Intermediate

VTP — VLAN Trunking Protocol

Cisco's protocol for sharing VLAN config across switches in the same VTP domain. Powerful, dangerous, and the reason every CCNA engineer learns the value of `vtp mode transparent`.

#24 Open topic →
Network Access Intermediate

Rapid STP & MSTP

Why classic 802.1D STP's 50-second convergence is unacceptable in 2026, and how RSTP and MSTP fix it — port roles, port states, sync mechanism, MST regions and instances.

#29 Open topic →
Network Access Intermediate

Private VLANs (PVLAN)

How Private VLANs add a second layer of isolation inside one Layer-3 subnet — primary + secondary VLANs, isolated vs community vs promiscuous ports, and real-world use cases (hotels, MDU, hosting).

#69 Open topic →

Wireless

6 topics
Wireless Foundational

Wireless LAN Basics

Definitive CCNA-level Wi-Fi fundamentals — SSID / BSS / ESS / BSSID terminology, autonomous vs lightweight APs, CAPWAP tunnel anatomy, WLC discovery (DHCP option 43 + DNS), Wi-Fi standards generations, security (WPA / WPA2 / WPA3), roaming, and 7 worked scenarios.

#15 Open topic →
Wireless Intermediate

WLAN Architectures — Autonomous, Centralized (WLC), Cloud, Embedded

Definitive CCNA-level WLAN architecture guide — autonomous vs centralized vs cloud-managed vs embedded WLC, split-MAC duty division, CAPWAP tunnel, AP modes (Local / FlexConnect / Bridge), WLC discovery, redundancy / N+1 / SSO, when each architecture fits.

#16 Open topic →
Wireless Foundational

Wi-Fi Security — WEP, WPA, WPA2, WPA3

Twenty-five years of wireless security in one page. Why WEP is broken, why WPA is a stop-gap, why WPA2 ruled for two decades, and what WPA3 actually fixes.

#17 Open topic →
Wireless Foundational

Wi-Fi 6, 6E, and 7 Features

What changed in 802.11ax (Wi-Fi 6), 6 GHz extension (6E), and 802.11be (Wi-Fi 7) — OFDMA, MU-MIMO, target wake time, 6 GHz spectrum, MLO, and what each one actually means for users.

#28 Open topic →
Wireless Foundational

Wireless RF Fundamentals

How Wi-Fi actually moves bits through the air — channels, bands, SNR, RSSI, free-space path loss, antenna patterns, and why your laptop disconnects in the conference room corner.

#38 Open topic →
Wireless Intermediate

Access Point Operating Modes

Cisco AP modes explained — Local, FlexConnect, Bridge / Mesh, Monitor, Sniffer, SE-Connect, Rogue Detector. When each is the right choice in real enterprise Wi-Fi deployments.

#39 Open topic →

IP Connectivity

10 topics
IP Connectivity Foundational

Inter-VLAN Routing

How devices in different VLANs talk to each other. Covers router-on-a-stick (with sub-interfaces), Layer-3 switch SVIs, and when to pick each.

#14 Open topic →
IP Connectivity Foundational

Static Routing

Definitive CCNA-level static routing guide — next-hop vs exit-interface vs fully-specified, default routes, floating statics, summary routes, recursive lookup, IPv6 statics, AD reference, 8 worked scenarios, and the static-routing debug workflow.

#20 Open topic →
IP Connectivity Foundational

Default Routing

The catch-all route every edge router needs. Covers static defaults, dynamic defaults (originated by OSPF/EIGRP/BGP), gateway of last resort, and the difference between a default and a summary route.

#21 Open topic →
IP Connectivity Foundational

Routing Decision Process

How a router actually decides where to forward a packet. Longest prefix match, administrative distance, and metric — in that order. Covers why a /30 static beats a /16 OSPF even though OSPF is the better protocol.

#22 Open topic →
IP Connectivity Intermediate

FHRP — HSRP, VRRP & GLBP

First-hop redundancy protocols. How two routers share one virtual IP so hosts don't notice when their default gateway fails. Covers HSRP states, election, preemption, and the GLBP load-balancing twist.

#23 Open topic →
IP Connectivity Foundational

Layer-3 Switch & SVI Routing

How a Layer-3 switch routes between VLANs at line rate using SVIs (Switched Virtual Interfaces) — the modern replacement for router-on-a-stick in any campus network.

#25 Open topic →
IP Connectivity Intermediate

OSPF Single-Area

Definitive CCNA-level OSPF guide — link-state mental model, seven neighbor states, LSA types, DR/BDR election, cost tuning, authentication, route summarization, common debug patterns, and 8 worked scenarios.

#30 Open topic →
IP Connectivity Intermediate

Route Summarization

Why aggregating many specific routes into one shorter prefix shrinks route tables, speeds convergence, and limits the blast radius of a flapping link. Covers manual, OSPF, and EIGRP summarization.

#32 Open topic →
IP Connectivity Intermediate

IPv6 SLAAC & DHCPv6

Two ways an IPv6 host gets an address. SLAAC has hosts auto-generate from a router-advertised prefix. DHCPv6 mirrors IPv4 DHCP. Covers RA/RS messages, EUI-64, privacy addresses, and stateful vs stateless DHCPv6.

#34 Open topic →
IP Connectivity Intermediate

IPv6 Transition Mechanisms

How networks bridge the IPv4 → IPv6 gap — dual-stack, tunneling (6to4, 6in4, GRE), NAT64 / DNS64, and the realistic 2026 migration patterns.

#68 Open topic →

IP Services

11 topics
IP Services Intermediate

HSRP vs VRRP vs GLBP — FHRP Compared

Side-by-side of the three First Hop Redundancy Protocols on Cisco gear. When HSRP wins, why VRRP is the open standard, how GLBP load-balances across multiple actives, and which to pick in 2026.

#26 Open topic →
IP Services Foundational

DHCP — Dynamic Host Configuration Protocol

Definitive CCNA-level DHCP guide — the DORA exchange step-by-step, packet anatomy, DHCP options table, lease renewal timing (T1/T2), Cisco IOS server + relay config, DHCPv6 brief, DHCP Snooping security, 8 worked scenarios, and the DHCP debug workflow.

#40 Open topic →
IP Services Foundational

NAT & PAT

Definitive CCNA-level NAT guide — static NAT, dynamic NAT, PAT/overload, the four inside/outside terms, port forwarding, CGNAT, NAT64 brief, hairpin NAT, translation table limits, 8 worked scenarios, and the NAT debug workflow.

#41 Open topic →
IP Services Foundational

DNS — Domain Name System

How www.example.com becomes an IP address. Covers the recursive query path (root → TLD → authoritative), record types (A, AAAA, CNAME, MX, PTR), TTL caching, and the most common DNS failure modes.

#42 Open topic →
IP Services Foundational

NTP — Network Time Protocol

How every device on the network ends up with the same clock. Covers stratum hierarchy, client and server config, authentication, and why broken NTP makes log correlation a nightmare.

#43 Open topic →
IP Services Foundational

Syslog

Send every device's log messages to a central server. Covers severity levels (0-7), facilities, message format, where to send logs (local buffer / console / monitor / server), and the eternal question of how much logging is too much.

#44 Open topic →
IP Services Foundational

QoS Basics

How routers and switches handle congestion — classifying packets, marking them with DSCP, queueing by priority, and shaping/policing traffic. Why VoIP and video deserve special treatment over file downloads.

#45 Open topic →
IP Services Foundational

SNMP — Simple Network Management Protocol

How monitoring systems pull metrics and receive alerts from network devices. Covers SNMPv1/v2c/v3, community strings, traps vs informs, MIB / OID navigation, and why SNMPv3 is the only one acceptable in 2026.

#46 Open topic →
IP Services Intermediate

IGMP & IGMP Snooping

How hosts join multicast groups (IGMP) and how a switch learns which ports actually want multicast traffic (snooping) — so it stops blasting video streams out every port.

#49 Open topic →
IP Services Intermediate

NTP Authentication & Security

How to harden NTP — authentication keys, peer/client/server roles done right, ACL restrictions, and why a bad clock breaks Kerberos, TLS, logs, and forensics.

#60 Open topic →
IP Services Foundational

DHCP Relay & IP Helper

How `ip helper-address` forwards DHCP DISCOVER broadcasts across Layer 3 boundaries so one DHCP server can serve many VLANs. Includes Option 82, the GIADDR field, and the relay troubleshooting flow.

#62 Open topic →

Security Fundamentals

10 topics
Security Fundamentals Foundational

Access Control Lists (ACLs)

Definitive CCNA-level ACL guide — first-match-wins, implicit deny, wildcard masks, standard vs extended vs named, direction (in vs out), the established keyword, time-based ACLs, named-ACL editing, 9 worked scenarios, and the ACL debug workflow.

#50 Open topic →
Security Fundamentals Foundational

Port Security

Lock a switch port to a specific MAC address (or addresses). Covers static, dynamic, and sticky learning, violation modes (protect / restrict / shutdown), and the err-disable recovery dance.

#51 Open topic →
Security Fundamentals Foundational

DHCP Snooping

Switch security feature that blocks rogue DHCP servers. Trusts one port (where the real server lives) and drops DHCP server messages from any other port. Foundation for Dynamic ARP Inspection too.

#52 Open topic →
Security Fundamentals Foundational

AAA · RADIUS & TACACS+

Authentication, Authorization, Accounting — centralize who can log in, what they can do, and what they did. Covers RADIUS vs TACACS+, method lists, and why every network with more than 5 devices uses centralized auth.

#53 Open topic →
Security Fundamentals Intermediate

802.1X — Port-Based Network Access Control

Lock every switch port until the connected device proves identity. Covers the supplicant / authenticator / auth server roles, EAPOL on the wire, and how 802.1X plugs into RADIUS for enterprise Wi-Fi and wired auth.

#54 Open topic →
Security Fundamentals Intermediate

VPN Basics — IPsec & SSL

How two separated networks (or one user and a network) can talk privately over the public internet. Covers site-to-site IPsec, remote-access SSL/TLS VPNs, IKE phases, and what 'tunnel' actually means.

#55 Open topic →
Security Fundamentals Foundational

Dynamic ARP Inspection (DAI)

The Layer-2 security feature that kills ARP spoofing dead. Validates every ARP packet against the DHCP Snooping binding table — bogus replies get dropped, trust your gateway again.

#56 Open topic →
Security Fundamentals Foundational

IP Source Guard (IPSG)

The fourth Layer-2 security feature. Validates the source IP of every IP packet against the DHCP Snooping binding table — blocking IP spoofing attacks at the access port.

#57 Open topic →
Security Fundamentals Foundational

Encryption Fundamentals

The cryptography networking engineers must understand — symmetric vs asymmetric, hashing, digital signatures, certificates, and where each is used in IPsec, TLS, SSH, and 802.1X.

#61 Open topic →
Security Fundamentals Foundational

Cybersecurity Threats & Mitigation

The threat landscape every network engineer must recognize — phishing, ransomware, MITM, DDoS, supply-chain attacks, insider threats — and the mitigation controls that actually move the needle.

#82 Open topic →

Automation & Programmability

7 topics
Automation & Programmability Foundational

REST APIs for Network Engineers

Modern Cisco devices expose REST APIs so you can configure them with HTTP requests and JSON instead of SSH and screen-scraping. Covers verbs (GET/POST/PUT/DELETE), authentication, data formats, and where REST fits in network automation.

#70 Open topic →
Automation & Programmability Foundational

Ansible for Network Engineers

Push configuration to dozens of Cisco devices from one YAML playbook. Covers inventory, modules, idempotency, and why Ansible became the default automation tool for network teams who don't want to write a custom Python script for every change.

#71 Open topic →
Automation & Programmability Foundational

JSON, YAML & XML for Network Engineers

The three data formats you'll meet doing network automation. JSON for APIs, YAML for configs/playbooks, XML for legacy and NETCONF. Same data, three syntaxes, different ergonomics.

#72 Open topic →
Automation & Programmability Foundational

NETCONF & YANG

The structured-data alternative to SSH-and-screen-scrape. Covers how NETCONF moves XML configs over SSH, what YANG models are, and where they fit alongside REST APIs in modern network automation.

#73 Open topic →
Automation & Programmability Foundational

Python for Network Engineers

Why Python is the de-facto language for network automation, plus the four libraries you'll actually use — Netmiko (SSH), NAPALM (vendor-agnostic), Nornir (parallel runner), and requests (REST APIs).

#74 Open topic →
Automation & Programmability Foundational

SDN & Controller-Based Networking

Software-Defined Networking explained. Why control plane and data plane were separated, what a network controller actually does, and where Cisco DNA Center, ACI, and Meraki fit in the landscape.

#75 Open topic →
Automation & Programmability Foundational

AI & ML in Network Operations

Where machine learning actually shows up in networks today — anomaly detection, predictive maintenance, generative AI assistants, and the difference between marketing AI and the real thing.

#83 Open topic →

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