Date of Issue: 07-01-2023

Troubleshooting Ethernet Networks

Introduction
Ethernet History and Architecture
Ethernet Physical Layer
  Signal Encoding
  Clock Synchronization
  Cisco's EtherChannel
Ethernet Media Access Control Layer
  Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
  Collision Domains
  Collisions on Networks with Hubs and Switches
  Full-Duplex Operations
    Proceed With Caution
    Auto-Negotiation
    Troubleshooting Auto-Negotiation
    Flow Control on Full-Duplex Links
  Enhancements to Ethernet Media Access Control for Gigabit Ethernet
  Ethernet Frames
    IPv6 and EtherTypes
    Ethernet Frame Sizes
    Is a Pad Merely a Place to Rest?
    Configuring and Troubleshooting Ethernet Frame Sizes
    Tunneling and Frame Lengths
    VLAN Tagging and Baby Giants
Collecting and Understanding Ethernet Performance Data
  Remote Monitoring
  The Show Interface Ethernet Command
    Is it really up?
    Capacity (Bandwidth) and Delay
    Utilization (Load)
    Exponential Averages
    Reliability
    Collision Rate
    Frame Corruption
    Broadcast and Multicast Rates
    Cisco's Broadcast Suppression Feature
Summary
References