SIP ALG Configuration Overview

The Session Initiation Protocol Application Layer Gateway (SIP ALG) is enabled by default on the device—no action is required to enable it. However, you might choose to fine-tune SIP ALG operations by using the following instructions:

1. Control SIP call activity. For instructions, see Example: Setting SIP ALG Call Duration and Timeouts.

2. Protect the SIP proxy server from denial-of-service (DoS) flood attacks. For instructions, see Example: Configuring SIP ALG DoS Attack Protection.

3. Enable unknown messages to pass when the session is in Network Address Translation (NAT) mode and route mode. For instructions, see Example: Allowing Unknown SIP ALG Message Types.

4. Accommodate proprietary SIP call flows. For instructions, see:

   • Retaining SIP ALG Hold Resources (J-Web Procedure)
   • Retaining SIP ALG Hold Resources (CLI Procedure)

Related Topics

• Junos OS Feature Support Reference for SRX Series and J Series Devices
• Understanding SIP ALGs
• Understanding SIP ALGs and NAT
• Verifying SIP ALG Configurations