On Jun 29, 2016, at 10:10 PM, Franck Martin <[email protected]> wrote: [ ... ] > And each router on IPv4 has to do an IP packet header checksum on a > variable length header, on IPv6 there is no packet header checksum. I'm not > sure how long does it take to perform on standard hardware: > https://en.wikipedia.org/wiki/IPv4_header_checksum
The majority of ethernet NICs--certainly those used on routers-- will have Rx and Tx hardware checksum capability which works both for the ethernet frame but also for generating or validating the inner protocol header checksums like IPv4, TCP, UDP, etc. Heck, TSO4 and TSO6 are widely available as well. While it is possible for a buggy implementation to need additional time to check the inner protocol checksums because someone had to disable part or all of the hardware Tx/Rx offload, that is not a normal situation. Regards, -- -Chuck _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool
