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Table of contents
Slide 1
Background
Terminology
Terminology (Cont.)
History
Example Routing Architecture
Why Run a Dynamic Routing Protocol?
Routing Information Protocol (RIP)
Introduction
Distance Vector Example
Distance Vector Example: 1) Startup
Distance Vector Example: 2) First Broadcast
Distance Vector Example: 2) First Broadcast (Cont.)
Distance Vector Example: 3) Second Broadcast
Distance Vector Example: 4) Stability
Distance Vector Example: 5) Link AB Goes Down
Distance Vector Example: 6) Updated Routing Tables
Distance Vector Example: 7) A and B Broadcast Their Tables
Distance Vector Example: 8) C, D, and E Broadcast Their Tables
Distance Vector Example: 9) Final Broadcast Updates A, B, and C
Problems With Distance Vector
Counting to Infinity
Trying to Avoid Count to Infinity
Slide 24
RIPv1 Fields
RIPv1 Example Packet
RIPv1 Design
RIPv1 Processing
Problems with RIPv1
RIPv2
RIPv2 Packet Format
RIPv2 New Fields
Open Shortest Path First (OSPF)
OSPF Advantages
Link State Routing
Link State Routing (cont.)
Link Cost
OSPF: Link State Routing Example (Using Dijkstra’s Algorithm)
Link State Example
Shortest Path Calculation
Dijkstra’s Algorithm
Dijkstra’s Algorithm Run on Our Example Network
Flooding Algorithm
Why is Link State Better Than Distance-Vector?
OSPF: Areas and Configuration
OSPF Areas
Types of OSPF Routers
OSPF Area Example
OSPF: The Protocol
OSPF Protocol
OSPF Common Header Fields
Slide 52
OSPF Phases
OSPF Example Packet
Issues With OSPF
Border Gateway Protocol (BGP)
Slide 57
Enter BGP
BGP Architecture
Border Router State
Advertising Aggregated Routes
Reachability and Route Aggregation
BGP Common Header Format
BGP Message Types
BGP UPDATE Packet Format
Example BGP Packet
Other Issues
References
Appendix: How Routers Work
Slide 70
High-End Router Design (As of about 2000)
High-End Router Design Using Network Processors
Today’s Routers
Forwarding Logic
Packet Processing Interface to Interface, Part 1: Link Layer
Packet Processing Interface to Interface, Part 2: IP Header Check
Packet Processing Interface to Interface, Part 3: Determine Destination
Packet Processing Interface to Interface, Part 4: Write Header, Give to Interface
Design for Speed
Author:
Mike Borella