mail protocol ports

One, what is the port. Before we start talking about ports, let's talk about what port is. Often heard on the network "My host opened a number of port, will not be invaded AH." "or" it would be safer to open that port. Again, my service should

e-mail protocol has SMTP, POP2, POP3, IMAP4, etc., are subordinate to the TCP/IP protocol cluster, by default, the connection is established through TCP ports 25, 110 and 143 respectively. For different purposes and functions, we will adjust the

There are a number of factors to consider when sending mail, including sending mail clients (generic encoding implementations), sending and receiving mail server settings, and so on. If you use a third-party mail server as the sending server, you

Hadoop-definitions of Computer Network PortsPort Introduction The ports described in this article are all logical ports, which refer to the ports in the TCP/IP protocol. The port number ranges from 0 to 65535, for example, port 80 used to browse Web

How E-mail Works   Every day the citizens of the Internet send each other billions of e-mail messages. if you are online a lot, you yourself may send a dozen or two e-mails each day without even thinking about it. obviusly, e-mail has

1024 The following is reserved for the system, and from 1024-65535 is used by the userFor personal writing applications, try not to use a port number between 0 and 1024.1024 to 65535 we can program with. This is not a Linux rule, it is the socket

Windows has many open ports. When you access the Internet, network viruses and hackers can connect to your computer through these ports. To change your system to a copper wall, you should close these ports, mainly including TCP 135, 139, 445, 593,

In network technology, port has two meanings: one is physical port, for example, ADSL modem, Hub, switch, router is used to connect other network equipment interface, such as RJ-45 port, SC port and so on. The second is the logical port, which

This article mainly introduces PHP based on the SMTP protocol to implement mail sending instance code, has a certain reference value, interested in small partners can refer to SMTP protocol When we use PHP's third-party library or tool class to

1. Port 21:Port Description: port 21 is mainly used for FTP (File Transfer Protocol) services. Suggestion: Some FTP servers can be used by hackers to log on anonymously. In addition, port 21 will be used by some Trojans, such as Blade Runner, FTP