Jeremy's IT Lab - CCNA Course Lecture Notes

Introduction

• Course on CCNA (Cisco Certified Network Associate)
• Focus on dynamic routing protocols
• Contrast with static routing
• Key topics: Layer 3, IP Connectivity, Dynamic Routing

Dynamic Routing vs. Static Routing

• Static Routing: Manually configure routes with 'IP ROUTE'
• Dynamic Routing: Configure a dynamic routing protocol; routers find best routes
• Advantages: Automatically adapts to network changes

Dynamic Routing Protocols Overview

• Covers a large portion of IP Connectivity for CCNA
• Focus on protocols: RIP, EIGRP, OSPF
• Importance of understanding dynamic routing protocols for exam

Dynamic Routing Protocols Characteristics

• Routing Protocols: Used by routers to advertise routes
• Metrics: Measure distance to destination
• Administrative Distance (AD): Determines best route among different protocols

Types of Dynamic Routing Protocols

• Interior Gateway Protocol (IGP): Within a single autonomous system
• Exterior Gateway Protocol (EGP): Between autonomous systems (e.g., BGP)
• IGP Algorithms: Distance vector (RIP, EIGRP) and link state (OSPF, IS-IS)

Key Protocols

• RIP: Uses hop count as a metric
• EIGRP: Uses bandwidth and delay as metrics
• OSPF: Uses cost based on bandwidth

Distance Vector Protocols

• Routing by Rumor: Distance vector logic
• Exchanges known destination networks and metrics
• Protocols: RIP and EIGRP

Link-State Protocols

• Develop a complete network map
• Protocols: OSPF and IS-IS

Metrics and Route Selection

• Metrics help determine the best route
• Low metric preferred
• Equal Cost MultiPath (ECMP): Load balancing over equal metric routes

Administrative Distance (AD)

• Used to compare different routing protocols
• Lower AD is more trustworthy
• Static routes: AD = 1; OSPF: AD = 110; RIP: AD = 120

Route Selection and ECMP

• If routes with same metrics, ECMP is used for load balancing
• AD determines the protocol preference
• Example: EIGRP preferred over RIP due to lower AD

Practice and Resources

• Recommended practice with Boson ExSim for CCNA
• Flashcards and packet tracer labs available

Closing Remarks

• Encouragement to use resources and practice quizzes
• Importance of understanding dynamic routing for CCNA exam