* Error messages should go to syslog in daemon mode.

* log by selecting protocol (TCP/UDP) and port
[NOT] PORT nb|<nb|>nb|all
* Type (can be cumulative)
TYPE TCP|UDP|ICMP

***** Rewrite output to accept modules ******
* be able to configure the output file format.

* Output how much time the log ran in output file (especially in case of a kill -HUP)

* HTML output
* CISCO accounting process compatible format : host source total_trafic number_of_packet

