You are the Exchange administrator based at site. All Exchange servers run Exchange Server 2003 at your site. Users report that a large number of unsolicited e-mail messages are delivered directly to the company e-mail addresses. You need to reduce the number of unsolicited e-mail messages recieved by company users, wothout affecting their ability to send and recieve legitimate e-mail messages. You cannot install any additional software on the exchange servers?
a. Configure the Exchange servers to perform reverse DNS lookups for all incoming SMTP connections
b. Write an Exchange server side scirpt that performs reverse DNS lokups on all incoming SMTP connections and rejects connections when the reverse lookup fails
c. Enable the junk mail feature on all e-mail client applications that do not have junk mail features, install mail-filtering software
d. Enable client-side mail filtering to delete all e-mail messages that do not contain the full e-mail addresses of the appropriate recipient
I think d. however what is the procedure of b. if say I do it.