Thread: Dynamic IPs
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Old 05-01-2004, 15:56   #3
rdhw
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Re: Dynamic IPs

Quote:
Originally Posted by Weltmeister
I'd like to know if ntl assigns IPs randomly from a 'pool' of IPs, or if they are more regularly assigned
Generally speaking, a broadband user will always get the same IP address back again, as the system records a pairing between the user's physical MAC address, and the IP address allocated by DHCP. For so long as that pairing is retained in the system, and for so long as the user retains the same physical MAC address, the user will retain the same IP address: this state can last for months if the user is regularly online. If the user is offline for a lengthy period, and the pairing expires, and the local DHCP address pool is heavily subscribed, then eventually the IP address will be leased to another user. And after a major NTL system reconfiguration, it is likely that IP addresses might change for everyone locally.
Quote:
what is the chance of two users in the same area repeatedly alternating between a single IP?
Vanishingly small, I would think. But if both users are in one home, sharing the broadband connection behind a NAT router (e.g. students in a shared house), then they will both appear to have the same IP address, even though they are different people.
Quote:
Also, do dialup and broadband customers draw from the same IP pool?
No, the pools for dialup and broadband users are distinct.
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