Wireshark is an open-source network protocol analyzer that allows users to capture and inspect network traffic in great detail. One of its most useful features is the ability to view and analyze the status codes of network packets, which can provide valuable insights when troubleshooting connectivity or performance issues.
Table of Contents
An Overview of Wireshark
Wireshark provides a graphical user interface that displays captured network data in an organized way, breaking it down by protocols, packet types, status codes, and more. Some key things it can do:
- Capture live packet data or open saved capture files
- Apply filters to only view certain packets of interest
- View granular details on individual packets
- Analyze complete TCP conversations and sequence numbers
- Generate rich statistical reports on network traffic
- Export packet data in a variety of formats
These features make Wireshark an indispensable tool for network administrators, cybersecurity professionals, and anyone who needs to analyze network traffic.
Capturing Packets with Wireshark
The first step to inspecting status codes is to capture some packet data. Here are the basic steps:
- Launch Wireshark and select the network interface you want to capture from
- Optionally apply capture filters to limit packet capture (e.g. by IP address)
- Click the blue shark fin icon to start packet capture
- Generate some network traffic that you want to inspect
- When ready, click the red square icon to stop capture
The result will be a list of all captured packets appearing in the top pane of Wireshark.
Finding Status Codes in TCP Packets
For TCP traffic, status codes appear under the hypertext transfer protocol (HTTP) protocol section of the packet details pane.
To view status codes:
- Click on a TCP packet in the top pane packet list
- Expand the Hypertext Transfer Protocol section in the packet details pane
- View the “Status Code” field value (e.g. 200, 404, 502, etc)
Common TCP status codes:
- 2xx = Success codes (200 = OK)
- 3xx = Redirection codes
- 4xx = Client error codes (400 = Bad Request, 404 = Not Found)
- 5xx = Server error codes (500 = Internal Server Error)
Finding Status Codes in UDP Packets
Since UDP is connectionless and does not establish sessions, the concept of status codes does not apply. Instead, Wireshark captures the raw data packets themselves.
If the UDP traffic is carrying higher level data, such as RTP for streaming audio/video, status codes may appear within the application data itself.
To view UDP packet data:
- Click on a UDP packet in the top pane
- Inspect the raw hexadecimal or ASCII formatted data shown in the data pane
Using Filters and Color Rules
Additional Wireshark features like filters and color rules can help narrow down packets of interest and highlight key information:
Filters
- Display filters: Show only specific packets (e.g. HTTP status codes)
- Capture filters: Only capture certain packets while sniffing
Color rules
- Tailor background and foreground colors based on protocol, status, errors, etc.
- Quickly visually identify important packets
Exporting Packets with Status Codes
Finally, once you’ve identified useful packets with status codes, you can export them for further analysis or to share with others:
- File > Export Packet Dissections
- File > Export Selected Packet Bytes
- File > Export Objects > HTTP
This just scratches the surface of what’s possible with Wireshark packet analysis. But being able to capture, filter, inspect, and export packets with status codes provides a solid foundation to start troubleshooting network issues or analyzing application behavior. With some practice, you’ll soon be digging into network traffic like a pro!
My Experience with Wireshark
I have used Wireshark extensively in my roles as a network engineer and system administrator. It has been an invaluable tool for gaining visibility into network communications and troubleshooting connectivity or performance problems.
Some examples where analyzing status codes in Wireshark has helped me resolve issues:
- Identifying malformed HTTP requests from a client application that was causing 500 errors
- Pinpointing load balancer misconfigurations leading to HTTP redirection loops
- Diagnosing TCP retransmission and zero window errors causing slow application performance
- Detecting UDP packet loss in a VoIP system based on gaps in RTP sequence numbers
Through proper filtering and status code analysis, I’ve been able to get to the root cause of many tricky network and application behavior issues over the years. Wireshark has saved me countless hours in troubleshooting and debugging efforts. I highly recommend that any IT professional get familiar with this powerful yet free analysis tool. It’s an indispensable arrow in your quiver for understanding what’s happening beneath the hood of any TCP/IP network.
Citations:
[1] https://www.wireshark.org/docs/wsug_html/
[2] https://www.alphr.com/find-status-code-wireshark/
[3] https://ask.wireshark.org/question/25708/wireshark-lab-problem-with-status-code/
[4] https://wiki.wireshark.org/Security
[5] https://www.wireshark.org/docs/wsdg_html/
[6] https://www.wireshark.org
[7] https://cybersecurity.att.com/blogs/security-essentials/network-traffic-analysis-using-wireshark
[8] https://www.wireshark.org/docs/wsdg_html_chunked/ChSrcDebug.html
[9] https://www.reddit.com/r/cybersecurity/comments/pq3d7d/wireshark_is_a_security_issue/
[10] https://zuli.io/unlocking-the-power-of-wireshark-for-wireless-networks
[11] https://www.varonis.com/blog/how-to-use-wireshark
[12] https://www.wireshark.org/docs/wsug_html_chunked/
[13] https://alliedtelesis.my.site.com/Support/CustomerCommunityArticle?articleId=ka01I000000fIKvQAM
[14] https://www.wireshark.org/security/
[15] https://www.linkedin.com/pulse/wireshark-tcp-tips-tricks-harinder-seera
[16] https://www.wireshark.org/docs/wsug_html_chunked/ChAdvTCPAnalysis.html
[17] https://www.socinvestigation.com/wireshark-filters-for-security-analyst/
[18] https://wiki.wireshark.org/NetworkTroubleshooting/Overview
[19] https://pitstop.manageengine.com/portal/en/kb/articles/how-to-use-wireshark-to-capture-and-inspect-network-trace-18-6-2019
[20] https://success.myshn.net/Skyhigh_Secure_Web_Gateway_(On_Prem)/Best_Practices/Common_Issues/Understand_HTTP_502_status_codes
[21] https://www.youtube.com/watch?v=kthHizueMiY
[22] https://www.comptia.org/content/articles/what-is-wireshark-and-how-to-use-it
[23] https://hackertarget.com/wireshark-tutorial-and-cheat-sheet/
[24] https://www.techtarget.com/searchnetworking/tutorial/Examine-a-captured-packet-using-Wireshark
[25] https://www.howtogeek.com/104278/how-to-use-wireshark-to-capture-filter-and-inspect-packets/
