Re: draft-boschi-ipfix-biflow and software implementation

On 07/Feb/06 10:47 -0500, Brian Trammell wrote:

Hi Brian,

> Alexandre,
> 
> On Feb 7, 2006, at 10:11 AM, Alexandre Dulaunoy wrote:
> 
> >I'll  try  to  "over"  summarize  back  what  I  understand  with  the
> >information       you      gave       me      and       the      draft
> >(draft-boschi-export-perpktinfo-01.txt) :
> >
> >The FlowID  is a 32bit id  unique across one observation  point and is
> >(always?) generated by the exporter.
> >
> >We   (at  SES   ASTRA  and   CSRRT-LU)  are   trying  to   generate  a
> >"unique/calculable" FlowID  among a specify dataset of  records. Why ?
> >We  have  a  bunch  of  "exporters" (routers,  devices)  with  various
> >versions  of Netflow  and  we have  to  live with  that  for the  time
> >being. What we are doing currently  ? we use a simple hash function to
> >generate a  "unique" FlowID per  data set based  on source/destination
> >IP,  source/destination  PORT  and  (protocol).   We  use  the  lowest
> >source/destination (IP/PORT) to generate a unified hash id per biflow.
> >
> >So it  seems that I was mixing  our and your definition  of FlowID but
> >what do  you think ?  Can  we call that  a FlowID or something  else ?
> >Have you think of a 'possible'  function to generate a FlowID based on
> >records ? Like  that, we can rebuild biflow(s)  from uniflow(s) ? Does
> >it make sense ?
>