Introduction to Cisco Networking - CCNA Prep

Explore layer one troubleshooting by verifying interface status to up-up, matching speed and duplex, and monitoring drops, crc errors, and collisions using show interface and tdr cable diagnostics.

Explore configuring vlans on switches, using access mode to send untagged host traffic and trunk mode to tag frames for multiple vlans across switch links.

Configure access VLANs on lab switches by setting switch ports to access mode, assigning data and voice VLANs, and verifying changes with show commands and CDP neighbor data.

Configure trunk ports between switches by setting trunk mode, selecting an encapsulation (ISL or 802.1Q) with a matching native vlan, and understanding trunk negotiation.

Learn how port security on switches controls learned MAC addresses to prevent unauthorized devices, using dynamic or static entries and sticky MAC addresses to protect cameras and other devices.

Explore how default gateways route traffic between subnets and enable communication across networks. See how hosts send to the gateway to reach distant destinations, with IP addressing examples.

Learn how routers forward IP packets from host to host, including MAC and IP addressing, ARP resolution, and the routing table with connected, static, and dynamic routes using EIGRP.

Explore how routing decisions use the longest prefix match, administrative distance, and routing metric to select the best path, with hands-on lab traces and static vs dynamic route comparisons.

Learn how default routes act as catch-all paths when no specific route matches, using static or learned routes to reach internet destinations.

Explore how route summarization reduces routing table size and improves convergence in dynamic routing protocols. Practice crafting a summarized 10.0.0.0/22 route by writing binary subnets to reach multiple destinations.

Learn to configure and verify router and switch interfaces, including speed and duplex negotiation, admin down or no shutdown, and distinguishing layer 2 and layer 3 ports, with show commands.

Enable ip routing on a layer 3 switch and create logical interfaces to route between VLANs. Learn to use interface vlan and verify with show ip interface brief.

Learn how a router on a stick uses a single physical interface with logical subinterfaces and VLAN tagging to route between multiple networks via a trunk.

Explore dynamic routing protocol classifications—distance vector, link state, and advanced distance vector—highlighting RIP v2, IGMP, and EIGRP, and distinguish interior protocols like OSPF and ISIS from exterior BGP.

RIPv2 is a classless distance-vector routing protocol that uses hop counts and multicast updates. It supports split horizon, route poisoning, no auto summary, and can originate a default route.

Configure rip version 2 on two routers, advertise the 10.0 networks, and enable rip on the wan links. Disable auto summary, set passive-interface default, and originate a default route.

Demonstrate rip v2 troubleshooting by inspecting show ip protocols outputs, enabling a passive interface back to active, correcting 172.16 network statements, and disabling auto summary while watching updates.

Map domain names to ip addresses through the domain name system using udp port 53, enabling dns lookups via dns servers that store name-to-ip mappings.

configure and understand dhcp for dynamic ip address assignment, including scope creation, excluding addresses, default gateway and dns information, and using ip helper addresses to relay requests to dhcp servers.

Configure network time protocol using a client-server model with public and internal ntp servers. Verify time accuracy by monitoring stratum levels and using show ntp status and show ntp associations.

Apply and test ip access lists to control traffic on interfaces, using standard and extended acl types, with named or numbered configurations, wildcard masks, time ranges, and optional logging.

Learn how NAT conserves public IPs using dynamic NAT pools, port address translation, and static NAT, with inside/outside interfaces and port forwarding.

Explore Cisco licensing concepts from image-based features to right-to-use licensing, and learn to generate, install, and verify license files using the device UDI and PAC numbers.

Learn how to configure and monitor centralized logging by sending device events to a remote log server, manage log levels from emergencies to debugging, and verify delivery and source interface.

Learn password security best practices for Cisco devices, using secret instead of password, enabling service password encryption, and understanding that type 7 can be decrypted.

Replace telnet with ssh for remote device management, generate 2048-bit rsa crypto keys after creating a domain, enable ssh version 2, and disable telnet by configuring transport input.

Configure local authentication on vty lines using locally stored user accounts with privilege 15, secret, and enable password, then enable aaa new-model for authentication, authorization, and accounting.

Configure a log in banner on network devices to warn and deter unauthorized access. Compare it with the message of the day banner.

Upgrade a Cisco router in the lab by downloading a newer image, verifying with an MD5 checksum, reviewing release notes, and loading to boot flash, then show version.

Learn Cisco password recovery by checking the config register with show version, breaking boot to bypass startup config with 0x2142, and resetting the enable password.