ZyXEL USG110/210/310 User Guide - Page 457

Chapter 15 ALG The following table describes the labels in this screen. Table 158 Configuration > Network > ALG LABEL DESCRIPTION Enable SIP ALG Enable SIP Transformations Turn on the SIP ALG to detect SIP traffic and help build SIP sessions through the Zyxel Device's NAT. Enabling the SIP ALG also allows you to use the application patrol to detect SIP traffic and manage the SIP traffic's bandwidth (see Chapter 36 on page 689). Select this to have the Zyxel Device modify IP addresses and port numbers embedded in the SIP data payload. Enable Configure SIP Inactivity Timeout SIP Media Inactivity Timeout You do not need to use this if you have a SIP device or server that will modify IP addresses and port numbers embedded in the SIP data payload. Select this option to have the Zyxel Device apply SIP media and signaling inactivity time out limits. These timeouts will take priority over the SIP session timeout "Expires" value in a SIP registration response packet. Use this field to set how many seconds (1~86400) the Zyxel Device will allow a SIP session to remain idle (without voice traffic) before dropping it. SIP Signaling Inactivity Timeout If no voice packets go through the SIP ALG before the timeout period expires, the Zyxel Device deletes the audio session. You cannot hear anything and you will need to make a new call to continue your conversation. Most SIP clients have an "expire" mechanism indicating the lifetime of signaling sessions. The SIP user agent sends registration packets to the SIP server periodically and keeps the session alive in the Zyxel Device. Restrict Peer to Peer Signaling Connection Restrict Peer to Peer Media Connection If the SIP client does not have this mechanism and makes no calls during the Zyxel Device SIP timeout, the Zyxel Device deletes the signaling session after the timeout period. Enter the SIP signaling session timeout value (1~86400). A signaling connection is used to set up the SIP connection. Enable this if you want signaling connections to only arrive from the IP address(es) you registered with. Signaling connections from other IP addresses will be dropped. A media connection is the audio transfer in a SIP connection. Enable this if you want media connections to only arrive from the IP address(es) you registered with. Media connections from other IP addresses will be dropped. SIP Signaling Port Additional SIP Signaling Port (UDP) for Transformations Enable H.323 ALG Enable H.323 Transformations You should disable this if have registered for cloud VoIP services. If you are using a custom UDP port number (not 5060) for SIP traffic, enter it here. Use the Add icon to add fields if you are also using SIP on additional UDP port numbers. If you are also using SIP on an additional UDP port number, enter it here. Turn on the H.323 ALG to detect H.323 traffic (used for audio communications) and help build H.323 sessions through the Zyxel Device's NAT. Enabling the H.323 ALG also allows you to use the application patrol to detect H.323 traffic and manage the H.323 traffic's bandwidth (see Chapter 36 on page 689). Select this to have the Zyxel Device modify IP addresses and port numbers embedded in the H.323 data payload. H.323 Signaling Port Additional H.323 Signaling Port for Transformations You do not need to use this if you have a H.323 device or server that will modify IP addresses and port numbers embedded in the H.323 data payload. If you are using a custom TCP port number (not 1720) for H.323 traffic, enter it here. If you are also using H.323 on an additional TCP port number, enter it here. ZyWALL USG Series User's Guide 457