"Yes, because that up there contains exactly *one* IP address - so I'd hardly call that "blocks"." Where I'm from we call it Blocks or Ipaddy. :-) "I have no idea what you are trying to tell me - you cannot "subnet out" one IP address to "your PIX firewall"." I wonder why I cant do that, seeing as have been doing it over 10 years. One often misguided approach to setting them up is, facing it directly into the open internet. Your as good as gone when someone hits up the ftp port on that shiny new PIX and tunnels right in. What I was trying to say was if you by 5 ip addresses you can take an address and subnet it out to other routers, switches and what ever else. There are lots of companys doing this these days because of the cost associated with them. Honestly this is all off topic from the original OP and what he needed, Those addresses were just randomly stuck in there for presentation example. Weather they right or wrong, he or she that is seeking the information should know to atleast to change that before using it. As for that I am not totally aware of what he really wants to accomplish. I in my later networking would not even use dhcp any more unless it was an install server. I would be doing it through Cisco PIX or Nortel. Simply because of the security record of cisco and nortel. But all in all CentOS gets my file services with samba as "DFS" and I hope to see a lot of progress on Directory Server.