1. Intro to Wireshark What is it? What does it do? Why do I need it?
Tech Talk Live 2018
Roy Hoover
Intro to Wireshark What is it? What does it do? Why do I need it?

2. Wireshark- What is it Packet Capture Protocol Analyzer
Network Analyzer

3. Wireshark- What does it do
Analyze bits on the wire (or in the air)
Break down packets into their components
See what’s actually happening on your network

4. Wireshark- Why do I need it
More detail on problems
Tech support requested a capture
Need to open a .PCAP file
Want to understand network traffic flow in greater detail
“Thorny” problems
Don’t get lost in the weeds!

5. Wireshark What is it Windows, OS X, Linux, and UNIX Open Source
Pcap
Previously called Ethereal
Promiscuous mode
Legal stuff

6. OSI Model 7 Application 6 Presentation 5 Session 4 Transport 3 Network
Telnet, 6
Presentation
Pict, GIF 5
Session
NFS, SQL 4
Transport
TCP,UDP,SPX 3
Network
IPv4, IPv6, IPX 2
Data Link
Ethernet, Token Ring 1
Physical
Copper, Fiber, Radio Waves

7. Ethernet Frame

8. Rabbit Hole Serial Communications
What settings does a Cisco console port use?
9600 8N1

9. Serial line sending “OK”
At 9600 Bits Per Second 1/(9600 bps) or 104 µs per bit.
Decimal Hex Binary
10 A 1010
11 B 1011
12 C 1100
13 D 1101
14 E 1110
15 F 1111 4F

10. IPv4 Packet
Ethernet Frame

11. IPv6 Packet Header
Ethernet Frame

12. Screen Shot

13. Getting Packets On your machine Hub Switch Tap Mirror a port SPAN
Watch your link utilization!
Mirror a port
SPAN
Tap

14. Live

16. Install Wireshark 2. 6. 0 (May 2, 2018) https://www. wireshark

17. Sample Captures

18. Questions?
Roy Hoover