A system for diagnosing a session initiation protocol (SIP) trunk configuration may include one or more processors coupled to memory. The one or more processors may be collectively operable to execute a diagnostics environment. The diagnostics environment may include an interface module operable to access data associated with a configuration including a set of configuration settings assignable to a SIP trunk. The set of configurations settings may be associated with respective layers and/or sublayers of a network connectivity model. A comparison module may be operable to determine a configuration status of one or more of the layers and/or sublayers associated with the SIP trunk. A display module may be operable to cause the configuration status to be displayed in a user interface. A method of diagnosing a SIP trunk configuration is also disclosed.