E-Mail is one of most application that is used in the internet. E-mail component is devided in Mail User Agent (MUA) and Mail Transfer Agent (MTA). The MUA is an e-mail application that connected to the email users. Applications which usually used by the e-mail users is Outlook, Pegasus, etc. Different from the MUA, the MTA is the email component that has a duty to transfer email that has been sent by the email users.
Email, which has the primary duty to deliver our message through the internet, has some problems that interfere the e-mail user. There are several problems that usually faced by e-mail users, such as e-mail bugged, counterfeited, spammed, relayed, or even mail bomb. E-mail bugged can occur in all places. it caused that email is the same with a postcard. This make email be very simple to be opened. To prevent this happened, we can encrypt our e-mail. There are several e-mail protection, such as PGP or PEM.
Spamming is also become another email problem that faced by the email users. The spamming action is sending an email to many email accounts. This is very annoying for email users cause the spam can make our box full with many inknown email. Largely unknown e-mail that detected as spam is usually contain useless advertisement for us. To prevent spam, we can do something such as make a protection to the MTA. MTA attached with RBL installed to prevent and detect spam in our e-mail.