Hi Friends Is that possible set a MAC reservation pool in each DHCP scope, then we can split clients pc into different subnetwork. eg, I want to group clients which I know in one sub network, the others should be limited in another subnetwork. or, is there other way/method can do it without third tool or VLAN? such as, you must type in your username/password which administrator gave to you temporarily, if you want browse internet in customer company. because these tools include VLAN is not convenient. but dhcp can do it easily. Thank for your any idea.

What you are trying to do really requires the use of VLANs, access-lists and/or dot1x for NAC. You can't accomplish it effectively using simply DHCP.Matt W. CCNP, CCDA, CCNA-S, RHCT, MCSE, MCSA, MCP+I, A+

Hi, Thanks for the post. I am wondering if you want to accomplish the following scenario: When a device or computer tries to connect to network, it shall first try to obtain ip address from DHCP Server. DHCP Server Callout DLL checks if this device MAC address is present in known list of MAC addresses configured by administrators. If it is present, device shall be allowed to obtain ip address or device requests shall be ignored based on action configured by administrator. If so, please understand that it just works at the DHCP Server level, not the specific DHCP Scope level. In this case, you will require VLAN as mattjw916 mentioned. If you are interested in MAC Address based filtering funtcion, please check the following article: http://blogs.technet.com/b/teamdhcp/archive/2007/10/03/dhcp-server-callout-dll-for-mac-address-based-filtering.aspx Thanks, MilesPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi mattjw916 , Miles Thanks for your info and url. Yeah, It reachs my idea almost, after I took look the new function of dhcp server in windows 2008 R2 which I have not touched before. I hope the dhcp team can move the mac filters into scope field, not server scope level. then I can control all clients whichever is guest's pc or my colleague's pc get ip from my dhcp server, not through VLAN or other tools. and easily split them into different address scope. that means I only know the mac address of my colleague's pc, not the guest's pc, and you can't forecast where they will sit. but i have to give them ip without delay 10 mintues or even more to modify parameters on my switch (layer3) or the other device. in the end, my target, I could control their route and surf internet on my firewall (Paloalto) base on the source ip or domain username (which guest does not have, only ip). or, I have to build two dhcp server, :-) Thanks