Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

For NAT (Network Address Translation) or any other packet header modifications, you need to recalculate checksums manually

Why doesn’t checksum offload in the NIC take care of that?





And I'm confused how they have to correct the TCP checksum but not the IPv4 header checksum...

Oh no we absolutely have to also correct the IPv4 header checksum!



Consider applying for YC's Winter 2026 batch! Applications are open till Nov 10

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: