North American Network Operators Group

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Re: Anti-spam System Idea

  • From: Niels Bakker
  • Date: Mon Feb 16 11:11:37 2004

* [email protected] (Lawrence Baldwin) [Mon 16 Feb 2004, 16:17 CET]:
> DHCP, though technically dynamic addressing is far less of a problem as
> IP address do NOT typically change very often...remember DHCP leases
> are renewed automatically by the client when the lease is 50% to
> expiration.
> Many DHCP clients also cache their previously leased IP (e.g. Windows)
> and explicitly request the same IP even across lease expirations...
> depending on the service provider, DHCP clients often maintain the same
> IP for months at a time (aka "sticky IP").  Some PPPoE gateways also
> maintain username to IP caches so sticky IPs can also result in that
> scenario as well.

Some ISPs configure their systems to hand out different IP addresses,
to discourage people from running servers (they'd have to update
www.theirdomain.tld each time their address would change).  This
practice gave dynamic dns services the opportunity to fill a need with

	-- Niels.

Blessed are the Watchmakers, for they shall inherit the earth.