said by dcurrey:Ok tried it. 5 minute mark ip stays. Wanted to do 10 but got distracted so I went for 1 hour 10 minutes. Ip remained the same still. So the OP might be out of luck or like you said mileage may vary.
A host will request the same IP it had (assuming it has memory of it).
A DHCP server will remember the IP Address/MAC Address combinations it has assigned, and will (a) not assign an IP to a different host prior to the lease expiration, and (b) give that IP back to the same host when possible.
If a host is offline
beyond the expiration of its DHCP lease, that IP may be assigned to someone else. If after expiration but the IP remains available, the original host
may get it again, if it remembers/requests that IP.
Key point here is when the DHCP lease expires. If you unplug your modem for an hour or two just prior to expiration, you
may get a new IP address next time, but no guarantees.
said by dcurrey:Given this info its almost the same as having Static ips.
Except that the service provider reserves the right to assign you to another IP pool at any time.