Sybex CCNA 640-802
Chapter 8: Layer-2 Switching
Instructor & Todd Lammle
Chapter 8 Objectives
The CCNA Topics Covered in this chapter
include:
• What is layer-2 switching
• Switching services
• B...
Layer 2 Switching
• Purposes for using switching
– Breaks up collision domains
– Cost-effective, resilient
internetwork
• ...
Before Layer 2 Switching
Switched LANs
Typical Switched Designs
One link to the server!
Switching Services
Layer 2 switching provides:
– Hardware-based bridging (ASIC)
– Wire speed
– Low latency
– Low cost
Limitations of Layer 2
Switching
• Must break up the collision
domains correctly.
• Make sure that users spend
80 percent ...
Bridging vs. LAN switching
Three Switch Functions at
Layer-2
Empty MAC table
How Switches Learn Hosts’
Locations
Switching Loops
Switching Loop Problems
Spanning-Tree Protocol (STP)
Solves Switching loops at layer 2
• STP
• Root Bridge
• BPDU
• Bridge ID
• Nonroot Bridge
•Ro...
Spanning-Tree Operations
• Selecting the root bridge
• Selecting the designated port
Switching Loops
Spanning-Tree Port States
• Blocking
• Listening
• Forwarding
• Disabled
Spanning-Tree Example
Written Labs and Review
Questions
– Open your books and go through all the
written labs and the review questions.
– Review...
Upcoming SlideShare
Loading in...5
×

Chapter8ccna

339

Published on

Published in: Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
339
On Slideshare
0
From Embeds
0
Number of Embeds
4
Actions
Shares
0
Downloads
0
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Chapter8ccna

  1. 1. Sybex CCNA 640-802 Chapter 8: Layer-2 Switching Instructor & Todd Lammle
  2. 2. Chapter 8 Objectives The CCNA Topics Covered in this chapter include: • What is layer-2 switching • Switching services • Bridges vs. LAN switching • Three switch functions • MAC table • Switching loops Spanning-Tree Protocol (STP) 2
  3. 3. Layer 2 Switching • Purposes for using switching – Breaks up collision domains – Cost-effective, resilient internetwork • Purpose for Spanning-Tree Protocol (STP) – Stops loops in layer 2 switched networks
  4. 4. Before Layer 2 Switching
  5. 5. Switched LANs
  6. 6. Typical Switched Designs
  7. 7. One link to the server!
  8. 8. Switching Services Layer 2 switching provides: – Hardware-based bridging (ASIC) – Wire speed – Low latency – Low cost
  9. 9. Limitations of Layer 2 Switching • Must break up the collision domains correctly. • Make sure that users spend 80 percent of their time on the local segment. • Switches do not break up broadcast domains by default.
  10. 10. Bridging vs. LAN switching
  11. 11. Three Switch Functions at Layer-2
  12. 12. Empty MAC table
  13. 13. How Switches Learn Hosts’ Locations
  14. 14. Switching Loops
  15. 15. Switching Loop Problems
  16. 16. Spanning-Tree Protocol (STP) Solves Switching loops at layer 2 • STP • Root Bridge • BPDU • Bridge ID • Nonroot Bridge •Root port •Designated port •Port cost •Nondesignated port •Forwarding port •Block port
  17. 17. Spanning-Tree Operations • Selecting the root bridge • Selecting the designated port
  18. 18. Switching Loops
  19. 19. Spanning-Tree Port States • Blocking • Listening • Forwarding • Disabled
  20. 20. Spanning-Tree Example
  21. 21. Written Labs and Review Questions – Open your books and go through all the written labs and the review questions. – Review the answers in class. 21

×