IMAP

The IMAP (Internet Message Access Protocol or Interactive Mail Access Protocol) is a protocol of communication for the email reception . The meant "Interactive Mail Access Protocol" has been valid until version 3, from the quarter in then is changed in "Internet Message Access Protocol". It puts into effect them version is "4 revision 1".

The protocol has been invented from Mark Crispin in 1986 [ 1 ] like more modern alternative to utilizzatissimo the POP. Both allow to a client to approach, to read and to cancel the email from a serveur, but with some differences. Here a directory of the characteristics of the IMAP but not of the POP:

* Access to the mail is online that off-linens

While the POP3 is used, the client it is connected in order to unload the new messages and then it is d3connectered. With the IMAP the client it remains connected and it answers to the demands that the customer makes through the interface; this allows to save time if there are messages of great dimensions.

* More customers can use the same case of mail

Protocol POP assumes that a solo client (customer) is connected to one determined mailbox (mail case), that one that it has been assigned. To the contrary the IMAP4 allows simultaneous logons the same one mailbox, supplying mechanisms in order to control the changes brings to you from every customer.

* Support to the access to single parts MIME of a message

The greater part of the email is transmitted in format MIME, that it allows a tree structure of the message, where every branch is a various content (headings, encloses or parts of it, message in a formed data, etc to you). Protocol IMAP4 allows to unload a single part MIME or quite sections of the parts, for having a preview of the message or in order to unload a mail without the rows enclose to you.

* Support for attributes of the messages held from the serveur.

Through the use of attributes, held on the serveur, defined in protocol IMAP4, every single client it can hold trace of every message, as an example for knowing if already it has been read or if answer has had one.

* Case access multiple of mail on the serveur

Some customers, with protocol IMAP4, can create, modify or cancel mailbox (of usual associated to cartelle) on the serveur. Moreover, this management of the mailbox, allows cartelle to have shared between various customers.

* Possibility to make searches on the serveur

The IMAP4 allows the client to ask the serveur which messages satisfies a sure criterion, in order to make, as an example, of the searches on the messages without having to unload them all.

* Support of a mechanism for the definition of extensions

In the detailed lists of the IMAP it is described like a serveur can make to know the customers if it has of the extra functionalities. Many extensions of the IMAP are much diffuse.

* Password criptate

With protocol POP the password they usually come sended in text, rendering easy, with one interception, the location of the password. With the IMAP it is possible criptare the password, even if serveur and client must find an agreement on the method.

The IMAP mainly is used in great network like university or companies, where a customer often changes emplacement: with the POP3, time would be necessary to unload the messages every that changes PC, while with the IMAP they can be only unloaded the new messages or be approached to a specific message without having to unload the others

The door predefined of demon IMAP onthe host is the 143. If a sure logon through SSL is used , then the door is the 993.