By the end of this lesson, the participant will be able to: ▫ Understand Ethernet frame structure ▫ Use Wireshark for resolving Ethernet problems

1. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 1
Network analysis Using Wireshark
Lesson 9:
Ethernet and LAN Switching

2. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 2
• By the end of this lesson, the participant will be able to:
▫ Understand Ethernet frame structure
▫ Use Wireshark for resolving Ethernet problems
Lesson Objectives

3. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 3
yoram@ndi-com.com
For More lectures, Courses & Keynote Speaking
Contact Me to:

4. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 4
Ethernet frame structure
What problems to look for
Chapter Content

5. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 5
The Ethernet Frame
Destination
MAC
Source
MAC
Protocol
Type
802.1q Data FCS
6 bytes 6 bytes 2 bytes 2 bytes 46–1,500 bytes 4 bytes
Priority CFI VLAN ID
Tag protocol
identifier
Tag control field
Proprietary
2-byte number
16 bits 3 bits 1 bit 12 bits
Protocol
Type
2 bytes
802.1Q
Tag
Tag ID: 8100 for 802.1Q
8a88 for 802.1ad
Priority: 8 levels, 0-7
CFI: Always set to “0”
VLAN ID: 0 – No VLAN
1 – Native VLAN
2-4096 Std. VLANs

6. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 6
Frame Information
Frame
details

7. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 7
Ethernet Information
Source
Address
Destination
Address

8. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 8
Ethernet frame structure
What problems to look for
Chapter Content

9. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 9
Checksum Errors
Bad
checksum

10. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 10
Broadcasts
10Mbps
~10µS’s between packets

11. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 11
Summary
• In this lesson we talked about:
▫ The Ethernet Protocol and what to look for in a capture fule
▫ LAN and Ethernet problems that might happen in your network
Thanks for your time
Yoram Orzach
yoram@ndi-com.com

12. Network Analysis Using Wireshark Version 2Network Analysis using Wireshark V.2 yoram@ndi-com.com
Network analysis using Wireshark V2 yoram@ndi-com.comPage 12
yoram@ndi-com.com
For More lectures, Courses & Keynote Speaking
Contact Me to: