Thanks to all those who offered advice .
My Original Message : 
I am looking into the possibility of implementing screend for pactet filtering 
in alpha-255 workstation running DU 4.0E with only 1 network card. My purpose to 
accomplish is to filter out unwanted IP packets into this host, just like the
running IP Filter in Sun Solaris for similar purpose.
The README file requires us  to run routed. Is it really needed ? 
Does anyone succeed with running screend in similar configuration.
Solution :
screend can only be used for filtering when the machine acts as gateway.
Suggested solution is to use /etc/ifaccess.conf to restrict access from
external hosts. 
Many thanks again to all who helped :
Marco.Luchini_at_acco-uk.co.uk
allen.belk_at_usm.edu
Nikola.Milutinovic_at_ev.co.yu
Regards
Phyllis H.M.Leung
Assistant Computer Officer
http://www.se.cuhk.edu.hk/~hmleung 
Dept. of SE&EM,The Chinese University of Hong Kong
Phone: 852-26098301 	FAX : 852-26035505
Received on Mon Dec 13 1999 - 04:23:38 NZDT