Mastering Routing & Switching - Zero-To-Hero

Explore the basics of local area networks (LANs), including switches on each floor, end devices, cabling, and the LAN boundary with routers, firewalls, and ISP connectivity.

Connect enterprises within a city or between cities using a metropolitan area network, with an ISP providing connectivity between branch offices in cities such as Bangalore, Chennai, and Delhi.

Define the internet as a global network of interconnected networks using IP as the common protocol, with IANA regulating IP address space and ISPs assigning unique public and private addresses.

Explore the three core internet services—web, email, and name services—driven by http/https, smtp, and dns, and see how dns lookups translate domain names to ip addresses.

Explore unicast, multicast, and broadcast communication as data moves between two PCs via a network interface card, using MAC and IPv4 addresses, with Ethernet basics, CSMA/CD, and UTP cables.

Explore how a 48-bit mac address uniquely identifies a NIC on Ethernet networks, including the oui and burned-in address, and how to view it with ipconfig.

Explore Ethernet basics: Thicknet and Thinnet bus topology, 10 Mbps shared bandwidth, collision domains and CSMA-CD with jam signals, and the shift from bus to star topology.

Explore cabling and connectors, including coaxial 10BASE2 and baseband signaling, UTP with RJ45, T568A/B, straight-through, crossover, and rollover cables, crimping tools, and AutoMDIX.

Compare copper UTP and STP cabling, trace cable categories from cat 1 to cat 7 and their speeds, and explore DAC cables, optical fiber, transceivers, and rollover console cables.

Explain class C addressing, where 24 network bits and 8 host bits define networks from 192.0.0.0 to 223.255.255.0, including the first valid IP and the broadcast address.

Understand how subnet masks accompany IPv4 addresses to define network and host parts, using class A/B/C defaults (255.0.0.0, 255.255.0.0, 255.255.255.0) and CIDR values (/8, /16, /24) to map networks.

Learn how two ethernet hosts use IP and MAC addresses, binary ending, ARP resolution, and ICMP ping exchanges to establish network connectivity.

Use Cisco Packet Tracer to demonstrate networking concepts by connecting two PCs with a copper crossover and configuring IPs like 10.1.1.1 and 10.1.1.2. Observe ARP, ICMP, and ping behavior.

explains router functionality as a layer 3 device that builds an IP routing table to route traffic between networks, using default gateways and dynamic routing protocols to determine best path.

Discover how firewalls operate from layer 3 to layer 7, block traffic by default, and require security policies to permit or drop traffic at the enterprise edge or data center.

Switches form the core of a LAN, connecting end devices and replacing hubs and bridges. Explore Catalyst and Nexus families, front panel ports, and Cat OS and NX OS.

Compare router vs switch: routers are layer three devices and switches are layer two, with mac/cam tables learning mac addresses and switches offering higher port density.

Explore Cisco catalyst switches' front panels, port layouts, and LEDs, including 48-port 1u CE 2960, console ports, and modular Nexus switches with line cards and scalable ports.

Explore how switches segment networks into one broadcast domain and multiple collision domains, and learn how VLANs, default VLAN 1, and auto negotiation shape network traffic.

Learn how a switch dynamically builds its MAC address table via gratuitous ARP, forwards broadcasts within a VLAN, and verifies IP uniqueness when devices configure 10.1.1.0/24 addresses.

Explore VLAN concepts as separate broadcast domains on switches and traffic isolation through VLAN IDs. Configure access and trunk ports, and observe MAC address table behavior.

Demonstrates vlan fundamentals and layer 2 segmentation by creating vlan 10 and 20, naming them marketing and sales, assigning access ports, and testing intra vlan communication versus inter vlan isolation.

Explain how trunking enables multiple VLAN traffic to share a single interface using 802.1Q tag in trunk ports, with access ports for end devices and inter-switch uplink communication.

Explain how trunk ports tag frames for all VLANs except the native VLAN, typically VLAN 1, so untagged traffic on VLAN 1 is delivered to its users.

Understand how spanning tree protocol prevents loops in a redundant three-switch topology by using BPDU exchange to elect a root switch, select root and designated ports, and block nonessential links.

Explore a four-switch topology running PVST+ with VLAN 10, demonstrating root switch selection by the lowest base MAC, root ports, designated ports, and blocking to form a forwarding tree.

Explore how per-vlan spanning tree computes a separate tree for each vlan, enabling per-vlan root switches through priority adjustments and vlan-id based bpdus, optimizing link usage.

Show how PVST plus expands PVST with security and convergence features like uplink fast, backbone fast, port fast, BPDU guard, root guard, and loop guard to speed topology recovery.