CommuniGate Pro
Version 5.2
Access
 
 
Overview

Account Access

The CommuniGate Pro Server allows users to use various client applications to access data in their Accounts: Mailboxes, Calendars, Contacts, Files, etc.

  • The POP module is a POP3 server; it allows users to retrieve E-mail messages from their INBOX Mailboxes (and, optionally, other mailboxes) using POP3-based mailers.
  • The IMAP module is an IMAP4rev1 server; it allows users to process E-mail messages in all Account Mailboxes using IMAP-based mailers.
  • The WebMail module is an HTTP (Web) application server; it that allows users to process E-mail messages in all Account Mailboxes and employ other CommuniGate Pro Server features using any Web browser.
  • The XIMSS module is an XML Messaging, Scheduling, and Signaling server; it allows users to make and control calls, to process E-mail messages and groupware items in all Account Mailboxes and employ other CommuniGate Pro Server features using "rich" Web-based clients (such as Flash®-based clients).
  • The MAPI module is an extension of the IMAP module; it allows users to access their Accounts and Mailboxes via the Microsoft® Windows MAPI (Mail API) and to use the Microsoft Outlook client in its full-featured "groupware" mode.
  • The AirSync module is an extension of the HTTP module; it allows users to access their Accounts and Mailboxes via the Microsoft® ActiveSync/AirSync protocol and to use the Windows Mobile clients to receive and send E-mail messages, and to synchronize Contacts, Calendar, and Tasks information with the Server Account data.
  • The CalDAV module is an extension of the HTTP module; it allows users to access their Calendar-type and Task-type Mailboxes via the CalDAV protocol.
  • The HTTP module is an HTTP server; it serves as a transport layer for other modules (such as the AirSync, and CalDAV modules, the XIMSS module in the HTTP Binding mode, etc.), and it provides access to Account File Storage, Mailboxes, and the Account Groupware information.
  • The FTP module is an FTP server; it provides access to Account File Storage.
  • The TFTP module is a TFTP server; it provides access to Account File Storage.
  • The ACAP module is an ACAP server; it allows users to manage their custom application settings stored in their Account datasets.

Access to Accounts

Every CommuniGate Pro Account can be accessed via the Access modules - POP, IMAP, XIMSS, WebUser Interface, FTP, XMPP, etc. Several client applications can use the same CommuniGate Pro Account at the same time, via the same, or different access modules.

Any Mailbox in any CommuniGate Pro Account can be shared: it can be accessed not only by the Account owner, but also by other users - if the Account owner or an Administrator grants those users access rights for that Mailbox.


Serving Multiple Domains

The main problem of serving multiple domains on one server is to provide access to accounts in different domains. To loog for the specified account, the server should get the name of the domain to look in.
Access to Accounts is similar to E-mail delivery and Signal processing: the server needs to know the "full account name" - an address in the accountName@domainName form.

There are several methods to pass the domain name to the server:

These methods can be used together: a limited number of Domains can be served using dedicated additional IP addresses, while other Domains are served using explicit domain name specifications.


Multihoming

Every access session begins with the authentication procedure: a client application sends a user (Account) name and a password to the Server.

The CommuniGate Pro Server tries to detect which Domain it should use to look for the specified Account name.

Sample:
The server computer has 2 IP addresses: 192.0.0.1 and 192.0.0.2.
The Server Main Domain is company.com, and the secondary Domains are client1.com and client2.com.
The DNS A-records for company.com is pointing to the IP address 192.0.0.1,
the A-record for the client1.com points to a dedicated IP address 192.0.0.2, while the A-records for the client2.com domain point to the same "main" IP address 192.0.0.1.
Each domain has an account info.

Three users configure their clients to access an account info, but they specify different names in their "server" settings: the first user specifies company.com, the second - client1.com, and the third user specifies client2.com.

When the first user starts her mailer:
  • The client application takes the specified "server" setting company.com, and it uses the Domain Name System A-records to resolve (convert) that name to the IP address 192.0.0.1.
  • The client establishes a connection with that address (which is one of 2 addresses of the Server computer), and it passes the user name info.
  • The Server detects a simple user name info and detects that this connection is established via the Server address 192.0.0.1.
  • The Server detects that this IP address is assigned to the Main Domain, so it adds the Main Domain name company.com to the specified simple name.
  • The Server gets the correct full account name info@company.com.

When the second user starts her client application:

  • The client takes the specified "server" setting client1.com, and it uses the Domain Name System A-records to resolve (convert) that name to the IP address 192.0.0.2.
  • The client establishes a connection with that address (which is one of 2 addresses of the server computer), and it passes the user name info.
  • The Server detects a simple user name info and detects that this connection is established via the server address 192.0.0.2.
  • The Server detects that this IP Address is assigned to the client1.com secondary Domain, so it adds that Domain name to the specified simple name.
  • The Server gets the correct full account name info@client1.com.

When the third user starts her client application:

  • The client takes the specified "server" setting client2.com, and it uses the Domain Name System A-records to resolve (convert) that name to the IP address 192.0.0.1.
  • The client establishes a connection with that address (which is one of 2 addresses of the Server computer), and it passes the user name info.
  • The server detects a simple user name info and detects that this connection is established via the Server address 192.0.0.1.
  • The Server detects that this IP address is assigned to the Main Domain, so it adds the Main Domain name company.com to the specified simple name.
  • The server gets the incorrect full account name info@company.com.

This happens because the client application (usually - an old POP or IMAP mailer, and FTP client, etc.) has not passed the information about the "server" name from its settings, and the only information the Server had was the IP address.

In order to solve this problem, the third user should specify the account name as info%client2.com, not just info. In this case, when this user starts the client application:
  • The client takes the specified "server" setting client2.com, and it uses the Domain Name System A-records to resolve (convert) that name to the IP address 192.0.0.1.
  • The client establishes a connection with that address (which is one of 2 addresses of the server computer), and it passes the user name info%client2.com.
  • The Server detects a full user name info%client2.com and it does not look at the IP addresses. It just converts the % symbol into the @ symbol.
  • The Server gets the correct full account name info@client2.com.

Note: most FTP clients work in the same way as the POP/IMAP mailers do, so FTP users are required to supply qualified Account names unless they connect to an IP Address assigned to their Domain.

Note:the MAPI Connector always sends a quialified Account Name: if users specify names without the @ or % symbols, the Connector adds the '@' symbol and Server Name setting value to the specified account name.

Note:the XMPP clients send the 'target domain' name along with the login name. If the specified login name does not contain the @ or % symbols, the Server adds the '@' symbol and "target domain" name to the login name.


Routing

When the full account name is composed, this name (address) is passed to the Router.

This means that all routing applied to E-mail and Signal addresses is also applied to the account names specified with mailer applications.

Sample:
The Account john has a john_smith alias;
all E-mail messages and Signals addressed to john_smith will be delivered to the Account john;
the user can specify either john or john_smith as the "account name" setting in his client applications - in both cases the Account john will be opened when those applications connect to the Server.
Sample:
The Account john has been moved from the main domain company.com to the domain client1.com, and it was renamed in j.smith. The administrator has created a Router record:
<John> = j.smith@client1.com;
all E-mails and Signals addressed to john@company.com will be sent to the Account j.smith in the client1.com Domain;
the user can still specify just john as the "account name" setting, and the same company.com "server" setting in his client application - but the Server will open the Account j.smith in the client1.com Domain.
Note:
do not create any Router record that redirects the Postmaster Account in the Main Domain. You will not be able to administer the Server, unless the postmaster account is redirected to an Account that has the Master access rights.
If you want the Postmaster E-mails and Signals to be directed to some other user, do not use the Router, but use the postmaster Account Rules instead.

CommuniGate® Pro Guide. Copyright © 1998-2009, Stalker Software, Inc.