Overview

Flood protection for MM1 messages prevents your subscribers from sending too many messages to your MMSC. Configuring flood protection for MM4 messages prevents another service provider from sending too many messages from the same subscriber to your MMSC.

Setting message flood thresholds

MM1 and MM4 flood protection

The FortiOS Carrier unit keeps track of the number of messages each subscriber sends for the length of time you specify. If the number of messages a subscriber sends exceeds the threshold, a configured action is taken. Possible actions are logging the flood, blocking or intercepting messages in the flood, archiving the flood messages, and sending an alert message to inform the administrator that the flood is occurring.

You can create three different thresholds to take different levels of action at different levels of activity.

With this highly configurable system, you can prevent subscribers from sending more messages than you determine is acceptable, or monitor anyone who exceeds the thresholds.

Setting message flood thresholds

A message flood occurs when a single subscriber sends a volume of messages that exceeds the flood threshold you set. The threshold defines the maximum number of messages allowed, the period during which the

Setting message flood thresholds

subscriber sent messages are considered, and the length of time the sender is restricted from sending messages after a flood is detected.

If a subscriber exceeds the message flood threshold and is blocked from sending more messages, any further attempts to send messages will re-start the block period. You must also enable logging for MMS Scanning > Bulk Messages in the Logging section of the MMS protection profile.

Example

For example, for the first threshold you may determine that any subscriber who sends more than 100 MM1 messages in an hour (60 minutes) will have all messages blocked for half an hour (30 minutes).

Using this example, if the subscriber exceeds the flood threshold, they are blocked from sending message for 30 minutes. If the subscriber tries to send any message after 15 minutes, the message will be blocked and the block period will be reset again to 30 minutes. The block period must expire with no attempts to send a message. Only then will the subscriber be allowed to send more messages.