When an IP address goes back into the DHCP. Can that old

huh?

>>57112620
im guessing: when you get a new ip. can people trace you using the old one

>>57112626
no, that makes no sense

>>57111578
Yes if the one tracking has access to the dhcp server

>>57111578
the only "reliable" identifier is the mac address, and that can be spoofed anyway

>>57111578
ISPs keep logs, yes
but only for a limited amount of time

>>57113210
It can go up to 2y depending on the country law

>>57111578
Are you using NAT? If so then the old IP address can still be traced back to your modem.
If you have a public IP assigned by your ISP via DHCP then it's unlikely for your lease to lapse and your IP to be replaced with a new one. IF that happens then only those with access to your ISPs logs can trace you. (yes, that may include your local police force).

if they know your mac address and have the old list of which ip is associated with which mac (held by your isp probably) they might be able to