The IMAP4 protocol
IMAP is Internet Message Access Protocol “, as the name implies, mainly provides a protocol to obtain information through Internet. IMAP4 is the fourth edition of IMAP, as POP3 is the third version of POP protocol. In the 21cn.com mail system, IMAP is a powerful e-mail access.
SMTP, POP3, IMAP protocol interpretation.
SMTP is called simple Mail transfer protocol ( Simple Mail Transfer Protocal ), the goal is to provide efficient, reliable message to the user.
Transmission. An important feature of SMTP is its ability to transmit messages in the relay, which can host relay mail through different network transmission
. In two kind of situations: one is the e-mail transmitted from the client to server; two is from one server to another server.
SMTP is a request / response protocol, it listens to port 25, to receive the user’s Mail request, and establish a connection to the SMTP and the remote Mail server
ImapBox at all post offices in the name of the directory you created is the same. So you can easily find the location of their own data storage.
The data stored in the post office is the most stable since the birth of the global Internet storage place, you do not have to worry about the data there will be any possibility of lost in the post office.