Anonymous Call - Avaya J100 Series Configuration Manual

Call scenario: Phone A (4000), B(4001), C(4002) are registered to Asterisk
B is busy / no answer / not reachble, A calls B, an automatic call back to A, A answers the calls, then
A automatic calls to C, C answers the call => A and C are in active call

1.2.13 Anonymous call

Configure Allow Anonymous Inbound SIP Calls
Allow Anonymous Inbound SIP Calls: Yes / No (allow / not allow anonymous inbound SIP calls)
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