Many of these organizations publish Blacklists of mail servers that are known spammers. Blacklists are used by thousands of ISPs as part of their Spam defense. In a skeptical internet communication environment, a legitimate email system can also end up being blacklisted, resulting in mail delivery problems and immeasurable costs in lost business. According to a study released in August by Return Path, Inc.’s, Assurance Services division, seventeen per cent of permission-based email messages get incorrectly blocked or filtered by the top 12 Internet service providers. Even emails addressed to confirmed recipients may never reach their inbox.
IP Blacklist blocks specific IP addresses (and IP ranges), message senders or message recipients (local mailboxes) as determined in the Blacklists. The IP Blacklist supports both IP addresses and subnet definitions. Addresses on the sender/recipient Blacklist can be defined by the address, simple wild carded mask or Perl-compatible regular expression. However, the problem with using an IP Blacklist is that it may cut off legitimate users trying to access site or blog or prevent them from sending email to users.
Domain Name Server (DNS) Black list is a list of IP addresses that are the source of unsolicited emails. By taking help of this list, system administrators can block unwanted domains. They refuse access to the server and prevent unwanted email messages. DNS Blacklists are usually maintained by anti-spam organizations or by individuals.
Spam Blacklists are lists of mail servers or open relays known to be used by spammers to deliver unwanted email. By placing these lists in their mail transport agent’s rules system, system administrators can block spam transmitted from these sources.
Email Black lists contain known mail servers and addresses used by spammers. With these lists in place, access to the server can be denied and unwanted email messages are discarded. However, your legitimate emails may also be blocked.
IP blockers & IP Blackholes
IP Black Hole lists are large repositories of IP addresses that are known to be spamming. These repositories use various reporting mechanisms ranging from human reporting to spam-trap email boxes to determine who is sending spam, and when a spammer is identified by IP or IP block, the spammer is added to the Black Hole list. Other ISPs and email providers can configure their email servers to query the Black Hole list any time a new email comes in. When a new mail arrives at the server, prior to putting it into the recipient’s mailbox, the server will examine the email, and trace its origin. Then it will ask the Black Hole list if this email came from a source that is a currently-know spammer. If the email does not originate from a source known to be spamming, it will be properly delivered into the recipient’s email box. If the mail fails the test and is flagged as spam, the mail will not be delivered, but rather will be moved to a storage box for future examination by either the system administrator or the end-user.
..more informations: www.szemuvegvilag.comFreand list:
1. www.szemuvegvilag.com – a látásér a látásmódért portál
2. www.szemuvegkeret.com – Napszemüveg és szemüvegkeret webáruház
3. www.zalkaoptika.szemuvegvilag.com– Zalka Attila látszerész mester oldala- a legjobb látszerész
4. www.pgah.hu – Profi Magyar Golf Sport Egyesület