Apr 15, 2020
How is TCP & UDP Checksum Calculated? Once the checksum is calculated, the result of the checksum will then go to the right place. That is the checksum field of the TCP header. Once the checksum is placed inside the real TCP header, the pseudo header temporarily created to calculate the checksum is then discarded. 4.6.4.3 Lab – Using Wireshark to Examine TCP and UDP Jun 26, 2019 Troubleshooting: SSH/TCP traffic fails in Contrail - J
What could cause TCP checksum failures? | AnandTech Forums
Jun 26, 2019 Troubleshooting: SSH/TCP traffic fails in Contrail - J
Once the checksum is calculated, the result of the checksum will then go to the right place. That is the checksum field of the TCP header. Once the checksum is placed inside the real TCP header, the pseudo header temporarily created to calculate the checksum is then discarded.
When I check the outgoing packet, every fields are good but one: the TCP checksum. Indeed, Wireshark tells me it is incorrect. In the following code, you can see how I build the packet (the IP headers are omitted because they seem to be OK). #define MINIMUM_TCP_HEADER_LENGTH 20 #define DEFAULT_TCP_WINDOW 32767 // [ tcpdump: cksum incorrect - Network Engineering Stack Exchange