1. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 Network Protocols Dynamic Host Configuration Protocol (DHCP)

2. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 Bootstrapping and auto-config Host loads boot image and/or config from network Station needs to know its own IP address Station only knows its hardware address Station minimally needs: Its IP address The default gateway/router Its subnet mask...and a DNS server (or more) would be nice

3. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 Older, less popular methods Reverse ARP (RARP) What is the IP address for MAC xxxx.yyyy.zzzz ICMP info/mask/router queries What is my IP, mask and router? BOOTP What is my config (and maybe boot loader file)?

4. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 To get configuration remotely Broadcast request no source IP yet, use 0.0.0.0 (this net, this host) destination? use 255.255.255.255 (limited bcast) Receive response From a configuration server Sends to our MAC, since we don't have a IP yet Routers can intercept/forward to remote servers

5. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 Typical DHCP startup behavior Client DHCP-DISCOVER-> DHCP-REQUEST-> DHCP-RELEASE-> Server <-DHCP-OFFER <-DHCP-ACK

6. TDC375 Autumn 03/04 John Kristoff - DePaul University 1 DHCP packet format