do ISPs keep track of end-user IP changes within thier network?

Mikael Abrahamsson swmike at
Thu Dec 12 05:36:16 UTC 2013

On Wed, 11 Dec 2013, Carlos Kamtha wrote:

> just a general curiousity question. it's been a long time since ive worked at an ISP.
> back then it was non-expiring DHCP leases and in some cases static IP for all.. (yes it was long ago..)
> Any feedback would be greatly appreciated..

Yes, it's very common to keep track of what user account/line had what IP 
at what time.

Mikael Abrahamsson    email: swmike at

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