Systems and methods for handling non-access stratum (NAS) incompatibility and scope of an assigned DCN

A method performed by a wireless communication device, WCD, the method comprising:

• transmitting, by the WCD, to a base station a request message comprising information identifying a requested Non Access Stratum, NAS, type, the WCD comprising at least one Dedicated Core network, DCN, Selection Assistance, DSA, indication, indicating a DCN and a DSA Origin indication indicating the origin of the DSA indication;
• receiving, at the WCD, as a result of transmitting the request message, a response message transmitted by the base station, the response message indicating that the requested NAS type is supported by the base station;
• and
• transmitting to the base station, in response to receiving the response message, a complete message comprising the DSA indication indicating to the base station the DCN selected by the WCD and comprising the DSA origin indication indicating the origin of the DSA indication.

A method performed by a base station communicating with a wireless communication device, WCD, residing in a cell served by the base station, the method comprising:

• generating, by the base station, a message comprising system information;
• transmitting, by the base station, the message comprising the system information, wherein the system information comprises information indicating that Non Access Stratum, NAS, type requests are supported by the base station;
• receiving, at the base station, a request message transmitted by the WCD, the request message comprising information identifying a requested NAS type;
• in response to receiving the request message, the base station determining whether the identified requested NAS type is supported;
• transmitting to the WCD, as a result of determining that the requested NAS type is supported, a response message comprising information indicating that the identified requested NAS type is supported by the base station;
• and
• receiving, as a result of transmitting the response message, a complete message transmitted by the WCD and comprising a Dedicated Core network, DCN, Selection Assistance, DSA, indication, indicating a DCN selected by the WCD and a DSA Origin indication indicating the origin of the DSA indication.

A method performed by a base station communicating with a wireless communication device, WCD, residing in a cell served by the base station, the method comprising:

• receiving, at the base station, a request message transmitted by the WCD, the request message comprising information identifying a requested NAS type;
• in response to receiving the request message, the base station determining whether the identified requested NAS type is supported;
• transmitting to the WCD, as a result of determining that the requested NAS type is supported, a response message comprising information indicating that the identified requested NAS type is supported by the base station;
• and
• receiving, as a result of transmitting the response message, a complete message transmitted by the WCD and comprising a Dedicated Core network, DCN, Selection Assistance, DSA, indication, indicating a DCN selected by the WCD and a DSA Origin indication indicating the origin of the DSA indication.