Applications

An SMTP Gateway is necessary?

ApplicGate offers a feature rich SMTP gateway mainly to change recipients and sender address in enterprise mail routings. It offers additional mail relays in security zones and security checks based on IP and sender details.

The SMTP gateway feature allows easy archiving of inbound or outbound messages traffic.

  • Easy modification of recipients addresses
  • Modification if sender addresses
  • Security policies for spam protection
  • Support for SMTP/TLS

Use Cases/TechInfo

Replacement of Mail Recipients

Any incoming mail can be sent to an additional recipient or to a different recipient. Various filters can be defined. “*” acts as wildcard. The SMTP command RCPT will be modified.

TECHINFO
  • To replace a mail recipient define the filter “OldRecipient>NewRecipient[,NewRecipient2]”.
  • Multiple filters can be defined.
  • NewRecipient2 is optional and defines an additional recipient.
  • Here are some examples:
    “*>*,c.d@aon.at” … sends all mails to second address c.d@aon.at also
    *@mycompany.com>*@aon.at” … replaces the mail domain.
    “user*@x.net>a.b@mycomp.com” … sends all matching mails to a.b@mycomp.com
    “*>*” .. no replacement (usually the last filter)
  • If there is no match an error message will be sent back.
SCHEMA
SMTP Gateway - Sender and Recipients Modification

Replacement of Senders

In certain configurations the sender of an SMTP mail must be changed to avoid conflicts.

Here the sender of any incoming mail can be replaced. Various filters can be defined. “*” acts as wildcard. The SMTP command MAIL will be modified.

TECHINFO
  • To replace a mail sender define the filter “OldSender>NewSender”.
  • Multiple filters can be defined.
  • Here are some examples:
    “*@mycompany.com>*@aon.at” …replaces the mail domain.
    “test*@x.com>prod*@aon.at” replaces e.g. test007@x.com by prod007@aon.at.
    If there is no match, the MAIL command will not be changed.
SCHEMA
SMTP Gateway - Sender and Recipients Modification

Spam Protection

Some mechanisms are built in to block spammers, such as lookup of MX records.

TECHINFO
  • An incoming mail can be blocked if
    > the mail domain specified in the FROM command does not have a valid MX record or the mail domain is not defined in the white list
    > unsupported SMTP commands are used
    > the recipient is not allowed.
  • A list of spammers will be created automatically.
    > This list can be managed by the administrator.
    > Entries can time out after a specified number of minutes.
SCHEMA
SMTP Gateway - SPAM Protection

FAQ + Techblog

Q: Is ApplicGate available for Linux also?

A: Yes, it is. Send an email to contact@applicgate.com and we will be glad to send you a version built for Linux.

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