Internet Message Access Protocol Version 4 (IMAP4) Clients


Internet Message Access Protocol Version 4 (IMAP4) Clients

As with POP3, IIS provides Internet Message Access Protocol version 4 (IMAP4) support to Exchange. This enables Internet e-mail applications using IMAP4 to retrieve data from an Exchange server. As with POP3, IMAP4 can only retrieve data and must use the SMTP functions of the Exchange Internet Mail Service (IMS) to send data.

One of the main differences between IMAP4 and POP3 is the Exchange folders they can access. As mentioned earlier, POP3 can access only the Inbox folder of a mailbox. IMAP4, however, can also access personal and public folders. IMAP4 also includes other advanced features (and non-POP3 features) such as search capabilities and selective downloading of messages or even only the attachment of a message.

The IMAP4 virtual server has many of the same properties as the POP3 virtual server, such as authentication, message format, and idle timeout. Some of the pages for these properties have additional attributes not present with POP3. IMAP4, for instance, also allows anonymous user access, meaning that an IMAP4 user without a Windows Server 2003 user account could access the server. Table 7.7 lists and describes the property pages and attributes of the IMAP4 object. Exercise 7.3 outlines the steps for configuring Outlook Express as an IMAP4 client.

Table 7.7: Property Pages of the IMAP4 Object

Property Page

Description

General

This page is used to assign an IP address to the virtual server. The default is for the server to have access to all IP interfaces configured on the server. You can select a specific IP address or use the Advanced button to configure IP address and TCP port information. This page is used to configure how long an idle IMAP4 connection will be held open before automatically closing and to limit the number of connections that the virtual server will allow.

The Limit Number Of Connections To option allows you to specify a maximum number of simultaneous connections that can be made to the IMAP4 virtual server.

The Include All Public Folders When A Folder List Is Requested option, which is enabled by default, permits a complete list of public folders to be sent to an IMAP4 client in response to the IMAP List command.

Some IMAP4 client applications, however, encounter poor performance when downloading a large list of public folders. If that is the case, this field can be cleared (i.e., unchecked).

The Enable Fast Message Retrieval option, which is enabled by default, permits an Exchange server to approximate the size of messages when reporting to an IMAP4 client application. Approximating message sizes increases the speed of message retrieval. Some IMAP4 client applications, however, require a server to report the exact message size. If that is the case, this field can be cleared (i.e., unchecked).

Access

An Exchange server can allow IMAP4 clients to be authenticated with the same protocols that are available with POP3. While the options are the same for both IMAP4 and POP3, each can be configured with a different set of authentication protocols. This is also true for any of the other attributes IMAP4 and POP3 have in common.

Message Format

This page is used to set the encoding method and character set used when converting Exchange messages for retrieval by IMAP4 clients.

The encoding options are as follows :

MIME: Both the message body and attachments will be encoded with MIME.

Provide Message Body As Plain Text: The message body will be placed in plain text and any attachments in MIME.

Provide Message Body As HTML: The message body will be placed in HTML format and any attachments in MIME. If both this option and the Provide Message Body As Plain Text option are selected, Exchange will generate both plain-text and HTML versions of the message body.

Calendaring

The options on this page are used to configure URL access to calendaring information by IMAP4 clients. This allows IMAP4 clients to use OWA as their calendaring client.

EXERCISE 7.3: Configuring Outlook Express as an IMAP4 Client
  1. Click Start > Programs > Outlook Express.

  2. Click the Tools menu, and then choose the Accounts command.

  3. Click the Add button, and then choose the Mail command.

  4. Enter a display name to appear in the From field of messages you send, and click Next to continue.

  5. Enter an e-mail address in the E-mail Address field, and click Next.

  6. Select the IMAP protocol from the drop-down menu.

  7. In the Incoming Mail field, enter the name of the Exchange server that will service IMAP4 requests .

  8. In the Outgoing Mail field, enter the name of the Exchange server that will service SMTP requests, and click Next.

  9. In the Account Name field, enter the username of the mailbox to which you will connect.

  10. Enter a password for the user, and click Next to go on.

  11. Click Finish.

  12. Outlook Express displays a dialog asking you whether you would like to download folders from the mail server you just configured. Click Yes to retrieve information on private folders other than your Inbox and any available public folders.

 
Note ‚  

Because of Exchange Server ‚ s support of IMAP4 and POP3, many Internet mail programs can be used as clients to Exchange Server.




MCSA[s]MCSE
MCSA[s]MCSE
ISBN: 735621527
EAN: N/A
Year: 2004
Pages: 160

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net