mqtt protocol

Label:IMAP (Internet Mail access protocol,internet) is formerly known as the Interactive Mail Access Protocol (Interactive mail, Access Protocol). IMAP was an email acquisition protocol developed by Stanford University in 1986. Its main role is that the mail client (for example, Ms Outlook Express) can obtain mail info

Both TCP and UDP are port-based protocols. TCP has links, and UDP has no links. The TCP protocol also drops packets (network problems, the data may be gone)The application is sent to the operating system's cache, and the operating system is removed from the cache, and once the data is lost, it is completely gone. TCP is reliable because the data in its own cache is emptied after it receives a confirmation message.How UDP works I took it out of my own

Commands and responses to the SMTP protocol From the previous communication model, you can see that the SMTP protocol's session between sending SMTP and receiving SMTP is done by sending SMTP commands and receiving an answer to SMTP feedback. After the communication link is established, Send SMTP send mail command message sender, if receive SMTP at this time can receive mail then make OK answer, and then send SMTP continue to Issue RCPT command to con

Software download for analysis: Wireshark-win32-1.10.2.exeRead the guided Tour1. Analyze and apply the ARP protocol2. Analyzing IP Protocols3. Analyzing the ICMP protocol1. Analysis of the format and content of ARP messages(1) The ARP request message of ping 172.18.3.132:000108000604000100e04c512ae8ac12038e000000000000ac120384Physical network Type hardware type:0001-ethernet (1)Protocol type Protocol TYPE:0

The similarities and differences between RTSP, RTMP, and HTTPCommon:1:RTSP RTMP HTTP is applied at the application layer.2: Theoretically RTSP rtmphttp can do live and on-demand, but generally do live with RTSP RTMP, do on-demand http. Video conferencing when the original SIP protocol, and now basically replaced by the RTMP protocol.Difference:1:http: Hypertext Transfer Protocol (FTP is a file Transfer

Let's look at what happens when we enter http://www.mycompany.com:8080/mydir/index.htmlin the browser, behind the scenes.First HTTP is an application layer of protocol, in this layer of protocol, is just a communication specification, that is, because the two sides to communicate, we have to agree to a specification beforehand.1. Connection when we enter such a request, first to establish a socket connectio

Reprint: http://easydarwin.org/article/Streaming/141.htmlThe similarities and differences between RTSP, RTMP, and HTTPCommon:1:RTSP RTMP HTTP is applied at the application layer.2: Theoretically RTSP rtmphttp can do live and on-demand, but generally do live with RTSP RTMP, do on-demand http. Video conferencing when the original SIP protocol, and now basically replaced by the RTMP protocol.Difference:1:http: Hypertext Transfer

Transfer http://blog.csdn.net/goodboy1881/article/details/668556 ------------------------------------------------------ Put the three Protocols together for learning because these three protocols are on the same layer. ARP is used to find the MAC address of the Ethernet NIC of the target host, and the IP address carries the message to be sent. The data link layer can get the data transmission information from ARP, and get the data information to be transmitted from the IP address.1. IP

There has been a problem for a long time, everyone is talking about the HTTP protocol, TCP protocol, IP protocol, what is the difference between them, what is the use, no one told me, recently read this "illustrated http" understand some of the film from the bookFirst, understand a transmission stream to expandFor example, HTTP is the first client in the Applicat

Put these three protocols together because the three protocols are on the same level, the ARP protocol is used to locate the target host's Ethernet NIC MAC address, and the IP hosts the message to be sent. The data link layer can get the data transfer information from ARP, and the data to be transmitted from IP.1.IP protocolThe IP protocol is the core of the IP protocol