Cisco CCNA: Networking Patterns, Routing & Switching

Explore the OSI seven-layer and TCP/IP four-layer network models, their layer functions, and key protocols like IP, ICMP, and Ethernet, with mnemonics to memorize the order.

Compare tcp and udp as transport layer protocols, noting port numbers, sockets, and multiplexing. Contrast tcp's connection oriented reliability and overhead with udp's fast, best-effort delivery for voip and streaming.

Explore tcp's error recovery and flow control with sequence numbers and acknowledgments, then contrast udp's connectionless, low-overhead header for speed.

Explore infrastructure components, including firewalls, stateful filtering, traffic identification, and security zones, and contrast autonomous access points with enterprise wireless LAN controllers.

Learn cloud computing models and services, including public, private, and hybrid clouds, plus SaaS, PaaS, and IaaS delivering pay-as-you-go on-demand resources over the internet.

Compare collapsed core and three-tier architectures within Cisco's hierarchical model, outlining core, distribution, and access layers, and discuss trade-offs in performance, scalability, and cost.

Compare physical and logical network topologies, exploring bus, star (hub and switch), full and partial mesh, ring, and hybrid designs, with emphasis on redundancy, collisions, and single points of failure.

Compare fiber optic and copper cabling, including UTP and STP, and learn to select cables by distance, environment, speed, and cost. Understand CAT grades and RJ-45 terminations.

Master IPv4 fundamentals, including the 32-bit address space and dotted decimal format. Use subnet masks and cidr notation to identify network prefixes and hosts.

Learn the three IPv4 address types—unicast, multicast, and broadcast—plus private IPv4 ranges (class a, b, c) and how NAT translates them for internet access.

Master IPv4 subnetting basics by reviewing binary math and powers of two, calculating network prefixes with subnet masks, understanding host ID bits, reserved addresses, and how subnetting scales networks.

Learn IPv4 subnetting by moving bits from the host ID to create subnets, compute the subnet mask, and determine usable hosts for class A, class B, and class C networks.

Explore variable length subnet masks (vlsm) to tailor subnets to host needs, using /25 for 100-host networks, /26 for 50-host networks, and /30 for the router link.

Discover IPv6 fundamentals, including its 128-bit addressing, 64/64 prefix and interface ID split, and a simpler 40-byte header.

Explore IPv6 address types—global unicast, unique local unicast, link-local unicast, multicast, and anycast—and learn prefixes like 2000::/3, FC/FD, FE80::; note no broadcast.

Learn how IPv6 interface IDs are formed and configured, including manual, UI-64, and privacy methods, with focus on 64-bit interface ID, MAC-derived IDs, seventh-bit flip, and loopback and unspecified addresses.

Explore IPv6 subnetting by examining the 64-bit interface ID and routing prefix. Use nibble boundaries and hex digits to create scalable subnets like /48, /44, and /64.

Explore IPv6 neighbor discovery protocol, including neighbor discovery and router discovery, roles in duplicate address detection and stateless address auto configuration, and the ICMPv6 messages NS, NA, RS, and RA.

Explore IPv6 stateless address autoconfiguration (SLAAC) via router solicitation and advertisement, learning how hosts obtain a prefix and self-configure link-local and global addresses.

Configure and troubleshoot IPv4 and IPv6 addressing on Windows hosts and Cisco routers using interface configuration mode with ip address commands, and verify connectivity with ping.

Explore server virtualization to consolidate underused resources on a single hardware platform. Learn about hypervisors, type one vs type two, and how virtual machines boost provisioning, uptime, and energy efficiency.

Explore layer two switching concepts: switches build dynamic or static MAC address tables, forward frames to the destination port, and flood unknown or broadcast traffic.

Learn how layer two switches flood frames in a broadcast domain, how VLANs and routers segment domains, and how spanning tree and MAC address tables prevent loops and manage addresses.

Analyze Ethernet frames at data link layer, detailing frame header and trailer, destination and source MAC addresses, the type field for IPv4 or IPv6, and frame check sequence field.

ARP lets hosts learn a neighbor's MAC via a broadcast request and unicast reply, caching the address in the ARP cache, while CDP and LDPE reveal direct neighbor details.

Discover how vlan segmentation creates separate logical networks, breaks up broadcast domains, and requires routers to enable inter-vlan routing across IP subnets.

explore vlan creation from global config to interface assignment, including multi-vlan creation, naming, voice vlan, management vlan with an svi, and verification with show vlan brief and show interface commands.

Explore 802.1Q trunks that carry multiple VLANs over a single link, using tagging and a native VLAN, with configuration tips and common native/allowed VLAN errors.

Learn how dynamic trunking protocol (dtp) negotiates trunk links between Cisco switches, compare dynamic auto and dynamic desirable modes, and apply troubleshooting to ensure proper trunk formation.

Explore how vtp synchronizes vlan databases across switches through server, client, and transparent modes, using domain names, revision numbers, advertisement messages, and domain passwords.

Learn to switch a device from VTP server to client, verify VLAN databases and revision numbers, and apply best practices: zero out revision, delete VLAN database, erase startup config, reload.

Discover how the spanning tree protocol prevents layer two loops by blocking redundant paths in networks with switch redundancy, reducing mac address instability, broadcast storms, and duplicate frames.

Explore how the spanning tree protocol uses bpdu frames to elect a route bridge, root ports, and designated ports per vlan, using cost and bridge id tie-breakers to block loops.

Explore different spanning tree protocol types, including PVS Plus and rapid PVS Plus, with per-VLAN instances, load balancing via separate route bridges, and port states from blocking to forwarding.

Configure the spanning tree protocol to elect a root bridge for VLANs, set primary and secondary route bridges, enable port fast on host-facing interfaces, and apply BPD guard.

Verify layer two topology with show CDP neighbors and show spanning tree, and identify root bridges and port roles for VLAN ten and VLAN 20.

Explore how ether channel bundles up to eight links for redundancy and load balancing, with spanning tree preventing loops and protocols like port aggregation protocol or VPI and ACP.

Configure an etherchannel by selecting interfaces for a channel group, setting a mode (lcp, agp, or on), and creating a port-channel interface; verify with show commands and correct any mismatches.

Explore switch stacking and aggregation to unite multiple switches into a single stack with a master switch, enabling redundancy, centralized management, and reduced spanning tree protocol diameter.

Learn switch interface troubleshooting and cabling issues, including half-duplex collisions, CSMA/CD, auto speed/duplex negotiation, and diagnosing duplex mismatches with show interface outputs.

Learn how routing delivers IP packets to the destination network and how hosts and routers use routing tables to choose the next hop.

Discover how routing tables map destination networks to next hops, with routes learned by connected, static, or dynamic sources (like RIP), and displayed by show ip route.

Learn how routing tables choose the best path using administrative distance and metrics. The video explains static vs dynamic routes, and the gateway of last resort for default routing.

Explore inter-VLAN routing options, including a router with access ports, router on a stick, and a layer three switch, to route traffic between VLANs. Assess efficiency and traffic flow for each method.

Learn how inter VLAN routing is achieved with a layer three switch using switched virtual interfaces (SVIs) for VLAN 10 and VLAN 20, enabling internal routing without an external router.

Compare static and dynamic routing by contrasting manual IP route configurations with protocols that learn and converge routes, and identify when to use each in small networks or with defaults.

Configure IPv4 static routes, including default routes and a gateway of last resort. Verify with show ip route; explore host routes and floating static routes with administrative distance.

Enable ipv6 routing, configure default and host static routes with exit interfaces or next hops, use fully specified routes, include link-local considerations, and verify with show ipv6 route.

Explore dynamic routing protocols, focusing on interior gateway protocols RIP, OSPF, ERP, and IS-IS, and how BGP serves as the exterior protocol between autonomous systems.

Configure rip version 2 as a distance-vector protocol using Bellman-Ford with a 15 hop limit and 30-second multicast updates; enable networks and passive interfaces.

Learn the fundamentals of OSPF, a link-state, classless routing protocol using cost based on bandwidth, areas, and LSAs to build a shortest path tree and routing table.

Explore how OSPF uses five message types—hello, database description, link state request, link state update, and link state acknowledgements—to build the link state database.

Explain how OSPF neighbor adjacencies form via hello exchanges and two-way state, with routers' IDs, and how DR/BDR elections on multi-access networks reduce adjacencies and drive convergence.

Configure single-area ospf v2 by enabling the ospf process, assigning a unique router id, and using the network command with wildcard masks to advertise interfaces in area zero.

Learn single-area OSPFv2 configuration and verification, covering OSPF cost calculations, reference bandwidth adjustments, and using show commands to inspect adjacency, link state database, and forwarding database.

Understand multiarea OSPF by using area zero backbone and area border routers to confine link-state databases, enabling inter-area routing via type three and four LSAs.

Learn how OSPF version three provides IPv4 and IPv6 routing, preserves many OSPFv2 similarities like link-state routing and cost metrics, and enables interface-based IPv6 OSPF with dual-stack migration.

Discover advanced ospf configurations and troubleshooting commands, including propagating a static default route through an ospf domain via an autonomous system border router, and verifying adjacencies and route sources.

Explore ERP, a distance-vector routing protocol with classless support, diffusing update algorithm and metric, reliable RTP, protocol dependent modules (PDM), and neighbor discovery leading to topology exchange and optimized routes.

Learn about EIGRP messages and the five packet types: hello, update, query, reply, and acknowledgment, and how reliability, unicast and multicast delivery, and TLV parameters shape adjacencies and routes.

Discover how the grp metric, a composite calculation using bandwidth, delay, load, and reliability, uses k1–k5 with default values to simplify and compute practical metrics, including an example.

Explore EIGRP successors and feasible successors. Understand how the IRP dual finite state machine enables fast convergence, routing loop prevention, and backup route management in the topology table.

Configure ERP for IPv4 by setting a common autonomous system number and router ID, then verify adjacencies with show ip protocols and show ip irp neighbor.

Enable IPv6 unicast routing, configure erp for IPv6 with the IPv6 router ip command and the autonomous system number, then verify neighbor adjacencies and learned routes.

Master network troubleshooting fundamentals through comprehensive documentation, including device configuration files and physical and logical topologies. Define baselines, verify with commands, and apply systematic fixes using bottom-up or top-down approaches.

Define wide area networks, their geographic scope and ownership, and outline WAN components from customer premises equipment to the toll network, plus point-to-point, hub-and-spoke, dual-home, and full-mesh topologies.

Examine private WAN infrastructures and leased line options, including CPE and DCE/CSU, and map MPLS and Metro Ethernet networks with C, P, PE routers, IGP, and interior BGP.

Explore fiber-based metro Ethernet as a WAN option. Learn about E line, Elon, and EE tree topologies, which use layer two circuits and shared subnets.

Explore public WAN options and secure private traffic with VPNs, including site-to-site, remote access, and dynamic multipoint VPNs, contrasting DSL, cable, wireless, and MPLS connectivity.

Explore point to point protocol for permanent two-site connections and layer two traffic encapsulation, and learn how LCP establishes the link while NCP enables multiple network layer protocols.

Configure point to point wan links by setting hdlc as the default, switching to pptp encapsulation, and verifying with ping; enable chap authentication and multi link for redundancy.

Learn how PPPoE over Ethernet enables tunneling and dynamic IP assignment over DSL, with CHAP authentication, dialer interfaces, and practical configuration and verification steps.

Develop troubleshooting skills for PPTP over Ethernet by verifying the physical layer, analyzing PPTP negotiation and CHAP authentication, and resolving MSS and MTU mismatches with debug outputs.

Explore GRE tunnels and Jiri tunnels for site-to-site VPNs, learn the encapsulation process and how to carry private networks over the internet, configure tunnel interfaces, and troubleshoot common issues.

Explore quality of service (QoS) concepts and analyze bandwidth, delay, jitter, and packet loss. Compare voice, video, and data requirements, noting UDP and TCP implications for reliability.

Learn how quality of service relies on traffic classification and marking, using layer 2 cos in 802.1q tags and layer 3 dscp/traffic class markings for end to end consistency.

Explore congestion avoidance and management tools for WANs, using WRED, shaping, policing, and queuing to protect TCP performance and reduce UDP packet loss for voice and video.

Explains border gateway protocol as an exterior gateway protocol that advertises networks between autonomous systems using path attributes over TCP port 179; highlights external BGP for multi-homing with multiple ISPs.

learn how the domain name system resolves hostnames to IP addresses via a DNS server over UDP port 53. see how a client queries and connects to the web server.

Learn how dynamic host configuration protocol (DHCP) assigns IP addresses and network settings via Discover, Offer, Request, and Acknowledgement exchanges, with lease renewals and optional relay or router-based servers.

Configure and verify dhcp on a Cisco router, creating a pool, excluding static addresses, and enabling relay with ip helper-address while testing with show ip dhcp binding and ip config.

Learn step-by-step dhcp troubleshooting, from verifying relay configurations and reachability between relay and server, to validating dhcp pools, default router, dns, and ftp server settings.

Learn how first hop redundancy protocols create a virtual gateway to prevent single points of failure, focusing on XRP elections, versions, and preemption for active and standby routers.

Configure and troubleshoot Hs-crp across two routers, set the virtual IP, group, and priorities, verify with show standby, and diagnose version or subnet mismatches and preemption.

Learn how multi group XRP enables load balanced redundancy with two routers using active and standby roles for each group, including virtual IPs and router on a stick sub interfaces.

Learn how NAT converts private addresses to public ones, covering inside local/global and outside local/global types, static, dynamic, and PAT, plus impacts on end-to-end connectivity.

Configure static NAT, dynamic NAT, and PAT with overload, using inside local to inside global mappings, assign internal and external interfaces, and verify with show ip nat translations.

Configure the network time protocol to synchronize device clocks via ntp servers and improve log correlation across the network.

Port security on switch interfaces restricts access by source MAC addresses, reducing unauthorized device risk. Shut down unused ports and use dynamic learning with sticky MAC addresses.

Analyze switch port security violations from mismatched source macs or full mac tables and compare protect, restrict, and shutdown actions with recovery via shutdown and no shutdown.

Examine inside LAN threats and their mitigations, from CDP reconnaissance to MAC table overflow and DHCP attacks, and learn practical protections like port security and disabling CDP.

Explore LAN security threats and mitigation, focusing on DHCP spoofing and starvation, and how DHCP snooping, rate limiting, binding tables, and 802.1X authentication enforce defense in depth on switches.

Explore access control lists (ACLs) for packet filtering, QoS, and routing policies, covering standard, extended, and named ACLs, inbound and outbound processing, and wildcard mask concepts.

Configure IPv4 standard ACLs by mastering top-down processing, correct permit/deny order, and outbound interface application; use named ACLs with sequence numbers for easy edits.

Configure and troubleshoot extended access control lists to filter on source and destination IP, protocol types, and ports, and learn their syntax, numbering, and order.

Configure ipv6 access control lists as named only, without numbered keywords, including two implicit permits for icmpv6 neighbor discovery and solicitation; manage via sequence numbers and apply inbound or outbound.

Learn how triple a, authentication, authorization, and accounting, enhances device management through local or server-based aaa with radius or tac ax for secure access and activity logging.

Master basic device hardening by using the enable secret for privilege access, encrypting passwords, and configuring ssh, local users, banner motd, and vty access restricted to ssh.

Explore SNMP, the simple network management protocol, its components—the NMS, the SNMP agent, and the MIB—and the five core messages. Compare v2c and v3 and their authentication options.

Configure SNMP version 2 and version 3 on a router, including community strings, traps, access lists, views including the ISO tree, and authentication with encryption for secure manager communication.

Monitor network events with syslog, learn severity levels 0-7, and configure Cisco devices to send messages to the console, terminal, and external syslog server with verification via show logging.

Explore device maintenance and management on Cisco iOS, including navigating file systems, backing up configurations with text capture, transferring files via FTP/TFTP, and verifying iOS images.

Master Cisco iOS license management: purchase a package, obtain a license file, install licenses for IP Base, Data, Unified Communications, and Security, then verify with show license and show version.

Master the initial Cisco device configuration, from the boot sequence and IOS loading to configuring a hostname and saving the startup configuration via the CLI.

Learn how ICMP echo-based IP SLA enables proactive network monitoring by testing connectivity to a DNS server, configuring an IP SLA operation, setting frequency and schedule, and viewing statistics.

Learn how span port mirroring uses a switch port analyzer to copy frames from source ports to a destination, enabling PC three to monitor traffic, including local and remote span.

Explain software defined networking and sd-wan, virtualizing the network with a centralized controller, enabling flow-based forwarding and programmable, scalable network architectures.

Summarize seven CCNA routing and switching topic areas, including network fundamentals, switching technologies, routing technologies, infrastructure services, security, and management, while learning to install and troubleshoot a medium-sized WAN network.