Cisco

EIGRP explained: how Cisco's Enhanced Interior Gateway Routing Protocol works, DUAL, successors, the metric, packet types and configuration.

Routing Information Protocol (RIP) explained: hop count, RIPv1 vs RIPv2 vs RIPng, timers, loop prevention, Cisco configuration and when to use it today.

What routing is and the main types of routing: static, default and dynamic routing, with Cisco configuration examples, pros and cons, and when to use each.

Administrative distance vs routing metrics: how routers choose the best path, what cost means in OSPF and RIP, and the default Cisco AD values table.

Routing protocol categories explained: autonomous systems and ASNs, interior gateway protocols (IGP), exterior gateway protocols (EGP) and BGP.

What a routing protocol is and how the main types compare: distance vector, link state, advanced distance vector and path vector.

What is a router? Learn router components (CPU, RAM, NVRAM, flash, ROM), the boot process and the basics of Cisco IOS modes.

The TCP/IP model explained: its four layers, key protocols at each layer, encapsulation, how it compares with OSI, and what happens when a page loads.

Types of transmission media in networking: twisted pair, coaxial and fibre, radio, microwave and infrared, plus straight-through, crossover and rollover cables.

An easy OSI model analogy: follow a bicycle sent by courier from Bangalore to Mumbai to see what each of the 7 layers does, then map it to real data.