Re: slightly OT: TCP checksum and RFC conformity

2005-11-17 Thread Andreas Bartelt
Hi, Damien Miller wrote: ... [EMAIL PROTECTED] djm]$ netstat -sp ip | grep -E '(bad.*checksum|total packets)' 61092730 total packets received 0 bad header checksums wouldn't netstat -sp tcp | grep -E '(bad.*checksum|total packets)' give the output of interest? (uptime 10

Re: slightly OT: TCP checksum and RFC conformity

2005-11-17 Thread Andreas Bartelt
Hi, Tobias Weingartner wrote: On Thursday, November 17, Andreas Bartelt wrote: As much better algorithms for error detection are known and PC performance (and also Internet traffic) has increased a lot since the introduction of TCP - do you think that the original checksum algorithm is

Re: slightly OT: TCP checksum and RFC conformity

2005-11-17 Thread Otto Moerbeek
On Thu, 17 Nov 2005, Andreas Bartelt wrote: Hi, Tobias Weingartner wrote: On Thursday, November 17, Andreas Bartelt wrote: As much better algorithms for error detection are known and PC performance (and also Internet traffic) has increased a lot since the introduction of TCP -

RE: Re: slightly OT: TCP checksum and RFC conformity

2005-11-17 Thread tony
[EMAIL PROTECTED] wrote: Hi, Damien Miller wrote: ... [EMAIL PROTECTED] djm]$ netstat -sp ip | grep -E '(bad.*checksum|total packets)' 61092730 total packets received 0 bad header checksums wouldn't netstat -sp tcp | grep -E '(bad.*checksum|total packets)' give the output

slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread Andreas Bartelt
Hi all, I was wondering why such a simple checksum algorithm is implemented in TCP. I suppose, it's because of the slow CPU performance many years ago. This algorithm looks so unreliable to me that it even can't protect against some pretty simple errors, which (I suppose) also could occur

Re: slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread Ted Unangst
On 11/16/05, Andreas Bartelt [EMAIL PROTECTED] wrote: I was wondering why such a simple checksum algorithm is implemented in TCP. I suppose, it's because of the slow CPU performance many years ago. and that's the way the great tcp gods of old said it must be. In RFC 1122 I've read that the

Re: slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread Christian Weisgerber
Andreas Bartelt [EMAIL PROTECTED] wrote: I was wondering why such a simple checksum algorithm is implemented in TCP. I suppose, it's because of the slow CPU performance many years ago. This algorithm looks so unreliable to me that it even can't protect against some pretty simple errors,

Re: slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread Andreas Bartelt
Hi, Ted Unangst wrote: ... good luck communicating with other tcp devices after you change your checksum to md5. the point is to be fast and catch some errors. also, type end-to-end into google. thanks for the interesting paper. I now understand why it makes sense to use a checksum at

Re: slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread chefren
On 11/17/05 00:39, Andreas Bartelt wrote: As much better algorithms for error detection are known What's better? Can those algorithms run with only a few hardware gates at 10Gbit speeds too? and PC performance (and also Internet traffic) has increased a lot since the introduction of TCP

Re: slightly OT: TCP checksum and RFC conformity

2005-11-16 Thread Damien Miller
On Thu, 17 Nov 2005, Andreas Bartelt wrote: As much better algorithms for error detection are known and PC performance (and also Internet traffic) has increased a lot since the introduction of TCP - do you think that the original checksum algorithm is still the best choice in terms of a