Nethvoice Proxy: Compatibility issue with initial SDP Offer using SRTP from NethVoice Proxy

[margit86]

Description:

When a phone receives an incoming call, the NethVoice Proxy originates an INVITE request that, by default, includes the SDP session to handle audio using SRTP.

This behavior can cause compatibility issues with phones that either do not have updated firmware or cannot be updated, and that do not correctly handle the initial SDP Offer sent by NethVoice Proxy.

Steps to Reproduce:

• Start an internal call between two phones.

• Capture and analyze the SIP traffic, focusing on the INVITE message sent by the NethVoice-Proxy to the called phone.

• Verify that the INVITE contains the SDP session with SRTP parameters.

• Check how the called phone handles the initial SDP Offer.

Expected Behavior:

The system should ensure compatibility with devices that cannot properly process the initial SDP Offer, possibly providing alternative configurations or fallbacks.

[Stell0]

1.3.5-testing.3

Test case:

• Configure an affected extension from wizard
• Disable encryption for it using the switch
• try to call the extension
• verify that the issue is no more reproducible