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SpiffyEh
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By default TCPDUMP limits the number of bytes it captures to 68. Why did they select 68 bytes? Does anyone know why?
Tcpdump is a network packet analyzer that captures and displays network traffic. The reason it only captures the first 68 bytes of a packet is because this is the default snap length, or the maximum amount of data that can be captured from each packet. This snap length can be adjusted using the -s flag.
Yes, you can increase the snap length using the -s flag followed by the desired number of bytes. Keep in mind that capturing larger amounts of data may impact the performance of tcpdump and your system.
It depends on the type of network traffic and the specific information you are looking for. If the important information is within the first 68 bytes, then yes, it will be missed. However, if you know the specific data you are looking for, you can adjust the snap length accordingly to ensure it is captured.
The default snap length of 68 bytes was chosen because it is the size of the standard Ethernet header. This allows tcpdump to capture the most important information from the packet, such as source and destination addresses, without capturing unnecessary data.
Yes, there are other network packet analyzers such as Wireshark, which have larger default snap lengths and allow for more customization. However, tcpdump is a lightweight and efficient tool that is commonly used in network troubleshooting and analysis.