too much administrative overhead. especially if you have a network of 50 or more nodes. unless you're using smaller subnets and using all valid IP's in the range, a user can still specify an IP in your network with matching netmask and have access because of the MAC filtering on my school network, I wasn't able to pull a DHCP address with a spare machine, so I used the above method. just checked IPCONFIG on a valid host, and matched the subnet.
----- Original Message ----- From: "Rick Darsey" <[EMAIL PROTECTED]> To: "jon kintner" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Tuesday, December 03, 2002 12:04 PM Subject: RE: Preventing DHCP from allocating IPs > > I know this sounds like a really bad way of doing this, but it is the only > way I can come up with off the top of my head: > > Turn of DHCP!! Statically assign all addresses in your LAN. If a visitor > wants access to your network, they will have to come to you to obtain the > address, or better yet, create a small DHCP pool that visitors can use, but > limit the size to prevent users you do not want from accessing the network. > The initial setup of the static addresses will take time, but the small DHCP > pool will still allow visitors to plug in when needed. > > Rick > > -----Original Message----- > From: jon kintner [mailto:[EMAIL PROTECTED]] > Sent: Monday, December 02, 2002 1:04 PM > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > Subject: Re: Preventing DHCP from allocating IPs > > > I know mac addresses can be spoofed pretty easily, but could you setup an > access list or filter that would disallow all mac addresses except for the > ones specified on your network(s)? > The initial setup would probably be tedious, but it's worked fairly well to > keep most unauthorized logins off the network at the college I attend. > > -jon kintner > > ----- Original Message ----- > From: "Sarbjit Singh Gill" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Monday, December 02, 2002 7:22 AM > Subject: Preventing DHCP from allocating IPs > > > > Greetings all, > > > > How do i prevent a client from getting an IP from my DHCP in an Ethernet > > network. I know i could reserve IPs for all other clients and nobody gets > an > > IP unless reserved earlier, but i have hundreds of clients. I frequently > > have visitors who need to plug in their laptops into the network and i > have > > visitors who are not allowed to plug in their laptops into the network and > > get IPs. I do not want these visitors who are not allowed to access the > > network to get an IP and start accessing internet through my network. > > > > What about in a wireless environment. How do i prevent it in a similar > > capacity. > > > > Kind Regards > > Gill > > > >
