Send the email process:
SMTP Port: 25
Command: {Mail from: {RCPT TO: } DATA . RSET} quit
------------------------ Receive the email process:
POP3 port: 110
Command: Return:
User OK ..... pass ok ..... STAT OK N L (n is a few letters, L is the total byte) List OK .... 1 L1 2 L2 ... N ln (L1 L2 ... LN = L) Retr OK I Li (i is the length of the i-th letter, Li is the length of the first letter) Body . Dele OK ....
quit
