Knowing others will give you a succinct answer, I would also suggest you can take a peek at RFC 1541 ftp://ftp.isi.edu/in-notes/rfc1541.txt for some details, such as the DHCP request packet format. In there you will find a field defined as giaddr ( Relay agent IP address, used in booting via a relay-agent. ) The router forwarding the DHCP request populates this field. The DHCP server reads the value in this field and makes the assignment from the appropriate scope. If you have nothing to do for several days, you can also check out this book: http://www.amazon.com/exec/obidos/ASIN/1578701376/o/qid=991282285/sr=2-1/ref =aps_sr_b_1_1/102-2752665-3470535 watch the wrap on this one hard to imagine one could fill a book with this stuff ;-> Chuck -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Lists Wizard Sent: Wednesday, May 30, 2001 9:02 PM To: [EMAIL PROTECTED] Subject: DHCP Servers and IP assignment [7:6562] Hello group, I have a nagging question about how the DHCP server assigns an IP address to a DHCP client from the correct pool of addresses. Let me give a scenario so that you understand my concerns. A host called Subnet_A _Client sends a dhcp request. The router's interface on subnet A is Ethernet_A. The router sends the dhcp request to subnet B, where the DHCP server resides. The router's interface on subnet B is Ethernet_B. My question is how will the DHCP server know that the dhcp request is coming from subnet A? Will the DHCP server unicast or broadcast the dhcp reply? To which address will the server unicast its dhcp reply? If someone can help me or refer me to a good online document that will answer my questions, I will appreciate it. Thanks Lw FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=6567&t=6562 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]