Hi Dave, Absolutely, that's why I said, "In situations where your IP address will vary because you are getting it from a DHCP pool then it's impossible to do any authentication against the IP address unless you allow/block the whole DHCP range."
Jenny -----Original Message----- From: Dave Watts [mailto:[EMAIL PROTECTED] Sent: 08 January 2006 18:01 To: CF-Talk Subject: RE: SPF? How to use? > I'm not sure why you are talking about DHCP addresses as > these are only used on an internal network and not across > the internet. DHCP addresses are issued on request from an > address pool by a DHCP server, typically on the Class A, B, > C reserved IP ranges (10.x.x.x, 172.16.x.x and 192.168.1.x). > They are also used by ISP's for client connections. While it's generally true that most DHCP leases are issued on internal networks using addresses that are translated through NAT to external addresses, there's no necessary connection between DHCP and internal networks. DHCP can be used to issue any sort of IP addresses, and those addresses can be public. Most ISPs that provide broadband connections do not use NAT, in my experience - that's why you can often connect to your home network if you know the external IP address. A lot of the infected computers that make up botnets happen to be using DHCP to get addresses from their ISPs. Dave Watts, CTO, Fig Leaf Software http://www.figleaf.com/ Fig Leaf Software provides the highest caliber vendor-authorized instruction at our training centers in Washington DC, Atlanta, Chicago, Baltimore, Northern Virginia, or on-site at your location. Visit http://training.figleaf.com/ for more information! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Message: http://www.houseoffusion.com/lists.cfm/link=i:4:228775 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
