IMAP (Internet Mail access protocol,internet) is formerly known as the Interactive Mail Access Protocol (Interactive mail, Access Protocol).

Source: Internet
Author: User
Tags imap mail account

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 information from the mail server via this protocol, download messages, and so on. The current authoritative definition is RFC3501. The IMAP protocol runs on top of the TCP/IP protocol, using a port of 143. The main difference between it and the POP3 protocol is that the user can not download all the messages, and can directly manipulate the messages on the server through the client.
Foreign names
Internet Mail Access Protocol
Abbreviation
Imap
Nickname
Interactive Mail Access Protocol
Role
Get message information from a mail server
Authoritative definition
RFC3501
Port
143
Directory
    1. 1 activating user Rights
    2. 2 features
    3. 3 features
    4. 4 Details
    1. ? Overview
    2. ? Advantages
    3. ? Application
    4. ? Design
    5. ? function
    1. ? operating mode
    2. ? for communication configuration
    3. ? HMI Integration
Activating user rights Not everyone agrees with this, but Google is still opening gmail free imIMAPAP access is another opportunity to get ahead in the Web mail contest. IMAP is not a new technology, and it's not for everyone. But it makes it easier for people to access Gmail from different locations on different devices. And it's going to put Microsoft and Yahoo! behind again. Gmail can be accessed via a Web page or pop, which allows the email client to download messages on the server but the client cannot give back any changes to the server when the message is taken. So if you downloaded five messages through the desktop client, read four, and moved three of them to another folder, the messages on the Gmail server are still "unread" and have not been moved. When you want to check the server again using a different device, you have to go through the process of processing the same message from the beginning. And IMAP is different, any changes you make on the client will be synchronized back to the server (when the network connection is normal), that is, the read messages will remain "read" status and moved items will remain moved, the same on all the devices checking the mail account. In other words, IMAP treats remote folders as local folders, which is useful. Especially when you use more than one interface to read and organize your mail (for example, the Office Web interface, the iphone used on the road, and clients like Thunderbird at home). Google has set up a help page to explain the difference between POP and IMAP, and how to set up IMAP for the client. IMAP is not a mail push (pushmail), nor is it as fast as the rumors say. However IMAP is the best widely supported mail protocol for multi-point access design. Features similar to the POP3 protocol, IMAP (Internet Message Access Protocol) also provides user-oriented mail collection services. The common version is IMAP4. IMAP4 improves the POP3, and users can browse through the header to decide whether to collect, delete, and retrieve specific parts of the message, and to create or change folders or mailboxes on the server. In addition to supporting the offline operation mode of the POP3 protocol, it also supports online and disconnected operations. It provides users with the option to receive mail from the mail server, server-based information processing functions and shared mailbox functions. IMAP4 's offline mode differs from POP3, which does not automatically remove messages that have been removed on the mail server, and its online mode and disconnected mode also make the mail server accessible as a "remote file server" for greater flexibility and convenience. IMAP4 supports multiple mailboxes. These features of IMAP4 are ideal for users who operate mail between different computers or terminals (for example, you can operate the same mailbox on a mobile phone, PAD, a mail agent on a PC), and those who use multiple mailboxes at the same time. function supportTwo modes of operation are connected and disconnected. When using POP3, the client is only connected to the server for a period of time until it downloads all the new information and the client disconnects. In IMAP, the client is connected to the server as long as the user interface is active and the download information content is needed. For users with many or very large messages, using the IMAP4 mode allows for faster response times. Enables multiple customers to connect to a single mailbox at the same time. The POP3 protocol assumes that the current connection to the mailbox is a unique connection. Instead, the IMAP4 protocol allows multiple users to access the mailbox at the same time providing a mechanism to enable customers to perceive other actions that are currently being made by users connected to the mailbox. Supports access to MIME parts and partial fetches in messages. Almost all Internet mail is transmitted in MIME format. MIME allows a message to contain a tree structure whose leaf nodes are a single content type rather than a leaf node that is a combination of multiple types. The IMAP4 protocol allows the client to obtain any independent MIME part and obtain part or all of the information. These mechanisms allow users to browse the contents of the message without having to download the attachment or to browse through the content. Supports retention of message status information on the server. By using flags defined in the IMAP4 protocol, clients can track message status, such as whether a message was read, replied to, or deleted. These identities are stored in theIMAPServer, so multiple customers accessing a mailbox at different times can perceive actions that other users have done. Supports access to multiple mailboxes on the server. IMAP4 clients can create, rename, or delete mailboxes (typically presented as folders to users) on the server. Support for multiple mailboxes also allows the server to provide access to shared and public folders. Support for server-side search. IMAP4 provides a mechanism for customers to ask the server to search for information that meets multiple criteria. In this mechanism, the client does not need to download all the information in the mailbox to complete these searches. Supports a well-defined extensibility mechanism. Learning from the experience of early Internet protocols, IMAP extensions define a clear mechanism. Many extensions to the original protocol have been proposed and widely used. Whether you use POP3 or IMAP4 to get the message, the client uses the SMTP protocol to send it. The mail client may be a POP client or an IMAP client, but it will use SMTP. Detailed overview component-based software tools for configuring communication in distributed automation solutions based on the Profinet standard for simple graphical communication configuration between system templates and line machines, for use with industrial Ethernet, Profinet Equipment Windows2000 and windowsxp operating environments from different vendors. Advantages compared with the communication function in the user program of each individual device, the main advantage of Simaticimap is that the communication configuration is simple (simply drag the line between the device's technical function interface). Application plant-wide engineering and configuration in a modular machine/plant, there must bemail client settings use IMAPCross-plant configuration tools to define the relationship between a stand-alone/plant component or a machine unit. Simaticimap is a component-based software tool. It is used to configure communication in a distributed automation scenario. Simaticimap is used to graph the data exchange between functional templates of the configuration technology. To ensure data exchange between intelligent field devices from different vendors, Simaticimap is also based on the profinet,profibusinternational (PNO) standard communication protocol. Profinet defines the communication based on TCPIP and industrial Ethernet from different manufacturers. The SIMATICIMAP can be integrated into existing solutions as an upper configuration tool, such as a total integrated automation system. In this case, you can use STEP7 to generate the library component. Design Simaticimap is a Windows-based application for configuring communication between a technology feature template (Profinet device) in a machine/factory. Simaticimap basically includes the following basic views: • Project tree: Used to manage all project resources (technical functions and equipment) and for navigation at the factory's automation level. • Technical Function Library: The technical function library includes the technical software functions required for a project. The Technical library components must be provided by the OEM (technologist). • Link Editor: Used to define the data exchange between technical function templates. • Network and topology views: used to define the technical functional structure between hardware devices, as well as system diagnostics (communication and Device status diagnostics) · Project views: for project management and overview of software features in projects. Feature Simaticimap can connect the software components that are managed in the library to each other. • In Simaticimap engineering tools, use "soft components" to represent each technical function machine/plant template. This can be used as a graphical display of software functions related to smart devices. • " The soft components and technical feature templates are assigned unique inputs and outputs (component interfaces) and can be used multiple times for simaticimap (Reuse library components). • Machines/factories can be built at many levels, as needed. Operation mode using Simaticimap, you can continue to create and debug projects as follows: • Generate soft components for each machine or factory template. • Interconnect various technical functional soft components in the Connection editor. • Configure the associated devices in the network topology. • Download the program and communication data to the device. The generation of software components each machine/device template has a separate user program and contains all the technical feature information for the template. The software component that describes the template is generated by the user program. According to the Profinet standard, "Software components" are generated through the device manufacturer's device-specific programming environment (for simatic, such as STEP7). The result is an XML document that completely describes the "soft components" and related data preservation (including deviceCompliance). Creating a component with STEP7 the PLC function of the technical function template can be programmed for the vendor of the technical function software component without modification. Programmers use the STEP7 language (IL, LD, etc.) to write PLC programs, but the interface data blocks must be used to define the technical function interfaces of the software components. The software component is then generated in the interactive screen of the STEP7 manager. The resulting software component is saved as an XML file, and its format is defined by the Profinet standard. You can then import the software components into the Simaticimap library. The communication configuration Simaticimap can be used to configure the data exchange between each machine and the factory template. Simaticimap connects the library elements that are based on technical functions, regardless of where they are manufactured or how they function. Project Engineers connect the technical functional software components to each other and configure the associated equipment in the network topology, and the project is then completed. Through online mode, project engineers can test and monitor communication between devices. From a technical point of view, Simaticimap has the following advantages: • Communication between software components, that is, communication between technical function templates can be defined in Simaticimap through a graphical interconnect. No programming knowledge required. • Consistent data for communication is generated based on engineering information and is downloaded to the device. The communication between the devices is downloaded via Ethernet. It does not require the installation of a device-specific programming tool like a download program. • All the variables required for general data access, such as visualization, access to the MES layer, etc., are automatically generated according to the engineering information (Opctag file). • Can test and diagnose all machines directly in the Simaticimap Inter-factory communication. To do this, you can graphically overview the network topology using Simaticimap. and can be mapped and soft components related to the device. HMI integration as long as browsing, users can access the data related to each profinet device through any OPC client application. Conditions are: SIMATICSoftnetS7 and SIMATICNETS7OPC Servers for industrial Ethernet (included in SIMATICSoftnetS7 for industrial Ethernet) and new OPC servers for profinet (SIMATICNETPNOPC server) 。

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IMAP (Internet Mail access protocol,internet) is formerly known as the Interactive Mail Access Protocol (Interactive mail, Access Protocol).

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