Hi, I have written an iptables rule to only allow certain mobile devices access to a specific web server. iptables -A filtermobile -p tcp --dport 80 -m string --to 700 --algo bm \ --string 'Mozilla/5.0 (Linux; Android’ -j ACCEPT When working on local lan and wireless the rule matches the phrase within the tcp / http header /user agent field and filters accordingly. On mobile data networks, the rule fails due to only reading up to 200 characters within the tcp / http header. Cannot work this one out as fragments have been disabled iptables -I INPUT 4 -p tcp -f -j DROP Any ideas? Many thanks The Layman