How can i allow or deny dhcp addresses to my clients

See http://articles.techrepublic.com.com/5100-10878_11-5498436.html

Hope this helps

You can go into the DHCP manager and 'reserve' your IP just for the existing devices in your network.

Hello jmsienrique,

good input from all on this topic, and using those tools and strategies listed above, I would also consider the strategy of making all fixed resources Static IP address.  By fixed resources I mean servers, printers, etc.  everything that serves others.  Even camera's, access cards, etc.  

Then create your scope for workstations / laptops and users with a 25% excess.. This will allow you some breathing room for future adds, guests, etc.

Now some may argue that worstations are fixed, and I agree that in some ways they are, however if you procede to make those static IP, this will create a management nightmare for you when you add / remove, etc.  assuming that all devices of different classes share the same subnet, I prefer to plan out my TCP/IP subnet allocation as follows:

192.168.x.1 -253

for address 1 - 10 Network device / resource Range
for address 11 - 20 Server Range
for address 21-40 Printer Range
for address 41-50 spare address space
for address 51 - 250 user range
for address 251 - 253 spare range

now this is just an example, and you can slice it any way you like.  But nontheless I recommend coming up with a standard and applying it company wide, so you don't have any management gaps and variances in configs.  

Good luck, and if you have any more questions feel free!!

John...

Let me ask how many addresses in the scope??

Now, how many of them are in the address pool??

Now, how do you want to filter. I believe there is a way to prevent DHCP from doning out addresses unless they perform an AD authentication first.

Then, there is MAC filtering. That is a pain in the behind to administer. I tried that for a while.

So, another thing I did is I created a sticky port on the switch. This means that when you plug in your computer the switch memorizes the MAC address of who plugged into it. Then, no one else can plug into it afterwards. That's a nice security feature. But, you need to have a managed switch.

So, how do you want to filter or block?

Oh, by the way, there is one other thing to think about.

Shorten your lease duration, so the leases that are no longer there will no longer occupy a lease from the DHCP address pool.

Then, shorten DNS scavaging to accomodate that DHCP change.

This is the recommended method for controlling leases. A lot less admin that way.

Hello
Well first thank all of you to write, so i have some dought about the software MacFilterCallout.msi , where can i download it ?
another, seeing the point of Create a New User classI do not understand what exactly do i need to type in the new class in the id Binary and Ascii, would you mind telling me what do i need to type, for more i atached you the screen
thanks again for all your support