Example: Configuring H.323 ALG DoS Attack Protection

This example shows how to configure the H.323 ALG DoS attack protection feature.

• Requirements
• Overview
• Configuration
• Verification

Requirements

Before you begin, understand and configure any Avaya H.323-specific features. See the Administrator Guide for Avaya Communication Manager, Avaya IP Telephony Implementation Guide, and Avaya Application Solutions IP Telephony Deployment Guide at http://support.avaya.com.

Overview

You can protect the H.323 gatekeeper from DoS flood attacks by limiting the range of Registration, Admission, and Status (RAS) messages per second it will attempt to process. The range is 2 to 50,000 messages per second, and the default value is 1000. This example limits the number of incoming RAS request messages to 5000 messages per second.

Configuration

J-Web Quick Configuration

Step-by-Step Procedure

To configure the H.323 ALG DoS attack protection feature:

1. Select Configure>Security>ALG.
2. Select the H323 tab.
3. In the Message flood gatekeeper threshold box, type 5000.
4. Click OK to check your configuration and save it as a candidate configuration.
5. If you are done configuring the device, click Commit Options>Commit.

Step-by-Step Procedure

To configure the H.323 ALG DoS attack protection feature:

1. Configure the gatekeeper for the H.323 ALG and set the threshold.
   [edit]user@host# set security alg h323 application-screen message-flood gatekeeper threshold 5000
2. If you are done configuring the device, commit the configuration.
   [edit]user@host# commit

Verification

To verify the configuration is working properly, enter the show security alg h323 command and the show security alg h323 counters command.

Related Topics

• Junos OS Feature Support Reference for SRX Series and J Series Devices
• Understanding H.323 ALG DoS Attack Protection
• H.323 ALG Configuration Overview