SonicWall

From Pbxnsip Wiki

In order to turn on functionality related to QoS and NAT-traversal for SIP/RTP in a SonicWall firewall, the feature "SIP Transformations" must be turned on.

For most flexibility for QoS, the SonicWall needs the "SonicOS Enhanced" version of the firmware. The latest version of SonicOS Enhanced is 3.2.0.3.

Unfortunately, the release of 3.2 introduced certain bugs related to its handling of RTP streams, causing problems like one-way audio in SIP applications. For example, if a call is both originated and terminated on the same device (e.g. a PSTN-gateway) in a pbxnsip system, one-way audio may occur.

Users experiencing problems of this kind with SonicWall should consider using SonicOS Enhanced version 3.1.0.14 . Though this version lacks certain features and bug fixes in other areas that were introduced in 3.2, it works better in VoIP applications.

Different DID numbers

If you are using different DID numbers, you should change the settings in the firewall. By default, it will accept only calls that are sent to registered extensions.