Jennifer Gavin-Wear said: > From: Jochem van Dieten [mailto:[EMAIL PROTECTED] >> >> But to get back on topic. Most ISPs use DHCP to assign IP >> addresses to customers. Even if these IP addresses are semi >> static (based on some form of option 82), these IPs are not >> identifiable for outsiders through the normal ARIN / RIPE etc >> registries like larger direct assignments are. Since about 80% of >> spam originates from hacked/infected end-users, some DNS RBLs >> list these DHCP addresses for pre-emptive blocking since they are >> mainly end-users anyway. That is the relevance of DHCP in spam >> blocking. > > I didn't know the RBL's were blocking whole address ranges, that's > pretty scary if you ask me!
Please be carefull in how you phrase the blocking process because you are feeding a very common misconception about RBLs: RBLs don't block anything. RBLs inform postmasters of the reputation of a certain IP address. If a postmaster makes the decision not to allow email from an IP address based on the reputation reports it gets from RBLs, that is the responsibility of the postmasetr. Postmasters block email, not RBLs. Yes, there are RBLs that list IP addresses solely for the reason they are DHCP addresses. Google for "dynablock" if you want to read up on one of them. There are also RBLs that list IP addresses solely for the reason they are from a certain country. (China, Korea, Brasil) There are also RBLs that list IP addresses solely for the reason they are from a certain ISP and that ISP harbours known spammers. (Google for "SPEWS") There are even RBLs that list legitimate mailservers that serve as a whitelist. It is the responsibility of the postmaster to select the proper mix of RBLs in tagging, blocking or whitelist mode. Jochem ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Message: http://www.houseoffusion.com/lists.cfm/link=i:4:228817 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
