Hi there, This is newly found that with all udp traffic filtered, SIP phone application doesn't have audio anymore. With wireshark analysis, it seems that STUN protocol gets upset in advance of RTP messages. It turns into some unknown format although we only pipe it through. Only way to workaround is to bypass all rtp ports. But we cannot do that as it is a huge range. Thanks in advance for any suggestion. Attached the case with/without rtp range bypassed. That was tested with linphone SIP phone application.

Hi there, Encountered something weird when doing beta test on Monterey Beta 8 while all good with Monterey Beta 6: We use system extension for NETransparentProxyProvider and we block QUIC traffics by below codes: override func handleNewUDPFlow(_ flow: NEAppProxyUDPFlow, initialRemoteEndpoint remoteEndpoint: NWEndpoint) -> Bool { let ep = remoteEndpoint as! NWHostEndpoint flow.open(withLocalEndpoint: nil) { [unowned self] error in guard error == nil else { flow.closeReadWithError(error) flow.closeWriteWithError(error) return } } if ep.port == "80" || ep.port == "443" { flow.closeReadWithError(nil) flow.closeWriteWithError(nil) return } ... } That works pretty well all through Big Sur to Monterey Beta 6. But when I upgraded to Beta 8 with the same, the system suffers: Chrome has no network access anymore. System extension get stuck when first time removed (need a second time to be removed) Sometimes the whole macOS has no network access at all. All these can be recovered by simply let QUIC traffics through or not capturing them. But we need to block such traffic in order that Chrome browser falls back to TCP mode. Thanks in advance for any suggestion! Regards Richard