The comparison module 48 may be operable to determine a (e.g., present) configuration status of one or more of the layers and/or sublayers associated with the trunk 29 in response to comparing the set of configuration settings 43 to the set of supported configuration options 54. In implementations, all possible configuration options 52 may not be known by the comparison module 48 when determining the configuration status. The comparison module 48 may be operable to determine the configuration status in response to comparing the set of configuration settings 43 to the set of supported combinations of the supported configuration options 54. In other implementations, the trunk configuration 42 may be accessible by and/or communicated to the comparison module 48 such that the trunk configuration 42 may be known to the comparison module 48. In implementations, one or more rules may be established to determine whether combinations of the configuration options 52 are supported or may otherwise be suboptimal. The diagnostics screen 58 may be arranged to identify unsupported and/or suboptimal combinations. For example, a low bandwidth codec (e.g., G729) without explicit dual-tone multi-frequency (DTMF) support (phone keys 0-9) may not be supported due to low audio quality not reliably passing the audio of the button press, whereas selection of another codec (e.g., G711) may be supported. As another example, configuring the SIP trunk 29 to pass audio encryption keys in unencrypted signaling may not be supported.