CCNA Presentation
- 1. Sybex CCNA 640-802 Chapter 9: VLAN’s Instructor & Todd Lammle
- 2. Chapter 9 Objectives The CCNA Topics Covered in this chapter include: • What is a VLAN? • VLAN Memberships • VLAN links • Frame tagging • VTP • Trunking • Configuring VLANs • Inter-VLAN Communication • Configuration examples 2
- 3. Virtual LANs (VLANs) • Definition: A logical grouping of network users and resources connected to administratively defined ports on a switch. – Smaller broadcast domains – Organized by: • Location • Function • Department • Application or protocol
- 4. Switches
- 5. Features of VLANs • Simplify network management • Provides a level of security over a flat network • Flexibility and Scalability
- 6. Broadcast Control • Broadcasts occur in every protocol • Bandwidth & Broadcasts • Flat network • VLANs & Broadcasts
- 8. Security • Flat network problems • VLANs
- 9. Flexibility & Scalability • Layer-2 switches only read frames – Can cause a switch to forward all broadcasts • VLANs – Essentially create broadcast domains • Greatly reduces broadcast traffic • Ability to add wanted users to a VLAN regardless of their physical location • Additional VLANs can be created when network growth consumes more bandwidth
- 10. Switched Network
- 11. Physical LANs Connected To A Router
- 12. VLANs Remove The Physical Boundary
- 13. VLAN Memberships • Static VLANs – Typical method of creating VLANs – Most secure • A switch port assigned to a VLAN always maintains that assignment until changed • Dynamic VLANs – Node assignment to a VLAN is automatic • MAC addresses, protocols, network addresses, etc – VLAN Management Policy Server (VMPS) • MAC address database for dynamic assignments • MAC-address to VLAN mapping
- 14. Identifying VLANs • Access links – A link that is part of only one VLAN • Trunk links – Carries multiple VLANs
- 16. Frame Tagging • Definition: A means of keeping track of users & frames as they travel the switch fabric & VLANs – User-defined ID assigned to each frame – VLAN ID is removed before exiting trunked links & access links
- 17. VLAN ID Methods • Inter-Switch Link (ISL) – Cisco proprietary – FastEthernet & Gibabit Ethernet only • IEEE 802.1q – Must use if trunking between Cisco & non-Cisco switch
- 18. Inter-Switch Link (ISL) Protocol • Definition: A means of explicitly tagging VLAN information onto an Ethernet frame – Allows VLANs to be multiplexed over a trunk line – Cisco proprietary – External tagging process
- 19. VLAN Trunk Protocol (VTP) • Purpose: to manage all configured VLANs across a switch internetwork & maintain consistency – Allows an administrator to add, delete, & rename VLANs
- 20. VTP Benefits • Benefits – Consistent configuration – Permits trunking over mixed networks – Accurate tracking – Dynamic reporting – Plug-and-Play • A VTP server must be created to manage VLANs
- 21. VTP Modes
- 22. VTP Modes of Operation • Server – Default for all Catalyst switches – Minimum one server for a VTP domain • Client – Receives information + sends/receives updates – Cannot make any changes • Transparent – Does not participate in a VTP domain but forwards VTP advertisements – Can add/delete VLANs – Locally significant
- 23. Router with Individual VLAN associations
- 25. Configuring VLANs • Creating VLANs • Assigning Switch Ports to VLANs • Configuring Trunk Ports • Configuring Inter-VLAN routing
- 26. Configuring VTP • Switches are configured to be VTP servers by default.
- 28. Example 2
- 29. Example 3
- 30. Example 4
- 31. Configuring Switching In Our Sample Internetwork
- 32. 2950C
- 33. 2950B
- 36. Written Labs and Review Questions – Open your books and go through all the written labs and the review questions. – Review the answers in class. 36