Question: In a 5G network, using the NGAP protocol, what does an NGAP-Group AVP value of '2' signify regarding the cause group for troubleshooting purposes?
Option 1: Radio Network Congestion
Option 2: Transport Layer Errors (e.g., IP issues)
Option 3: Non-Access Stratum (NAS) Protocol Issues
Option 4: Miscellaneous Hardware Failures
Explanation: The NGAP-Group AVP is used to indicate the group of the NGAP cause in a 5G network's NG-RAN protocol. According to the defined values, an NGAP-Group AVP value of '2' specifically indicates that the cause group is related to "nas" (Non-Access Stratum), which pertains to NAS protocol issues. This helps in pinpointing the source of problems during troubleshooting, in this case, focusing on NAS-related communication errors between the UE and the network.