hi , i already read that articale but it is not having clear explaination about how actually in kernel it works? what i am not getting from diagram 3 and 4 is that what exactly has been put in skb in diagram 4 so that it looks like | headroom | data area| skb_put area | tailroom from diagram 3 | headroom | data area | tailroom regards, parag. On Thu, 29 Apr 2004 mohanlal jangir wrote : >Here is an excellent tutorial by Alan Cox >http://www.tldp.org/LDP/khg/HyperNews/get/net/net-intro.html > >Regards >Mohanlal >