目录
1. NG SETUP过程
1.1 NG SETUP定义
NG Setup过程用来交换NG-RAN节点和AMF在NG-C接口上正确互操作所需的应用程序级数据。该程序为TNL关联开始运行后触发的第一个NGAP程序。该过程使用非UE相关的信令。
此过程将擦除两个节点中的任何现有应用程序级配置数据，将其替换为接收到的数据，并清除NG-RAN节点上的AMF过载状态信息。如果NG-RAN节点和AMF不同意保留UE上下文，则此过程还会像NG重置过程一样重新初始化NGAP UE相关上下文，并擦除两个节点中的所有相关信令连接。
1.2 NG建立成功
NG SETUP：成功运行
NG-RAN向AMF发送NG SETUP REQUEST消息来建立NG连接。AMF以NG SETUP RESPONSE消息进行响应。
如果NG SETUP REQUEST消息中Supported TA List字段包含的Configured TAC Indication设置为“true”，AMF可以考虑向此NG-RAN节点发送NG-C信令。
如果NG SETUP REQUEST消息中的UE Retention Information 设置为“ues-retained”，AMF将保留现有的UE上下文和信令连接，并将NG SETUP RESPONSE消息中的UE Retention Information 设置为“ues-retained”。
AMF应将Backup AMF Name包含在NG SETUP RESPONSE消息的Served GUAMI List中。如果NG-RAN支持的话，NG-RAN在执行AMF重选时，应先考虑Backup AMF Name所指示的AMF。
如果NG SETUP RESPONSE消息中包含有GUAMI Type，则NG-RAN节点应存储收到的值，将其用于进一步的AMF选择。
如果NG SETUP REQUEST消息中包含RAN Node Name，则AMF可以使用该Name作为NG-RAN节点的可读名称。
如果NG SETUP RESPONSE消息中包含AMF Name，则NG-RAN节点可以使用该Name作为AMF的可读名称。
如果NG SETUP REQUEST消息中包含NB-IoT Default Paging DRX，AMF应将其考虑在内进行寻呼。
如果NG SETUP REQUEST消息中包含RAT Information，AMF应按照TS 23.502【10】中的规定处理该信息。
1.3 NG建立失败
NG设置：操作失败
如果AMF不能接受NG Setup，则回应NG SETUP FAILURE消息，并携带相应的原因值。
如果NG SETUP FAILURE消息包括Time to Wait，则NG-RAN节点至少应该等待所指示的时间，然后再向同一AMF重新启动NG Setup过程。
1.4 异常情况
如果NG-RAN节点通过发送包括PLMN标识的NG SETUP REQUEST消息来启动该过程，并且AMF不识别由NG-RAN节点提供的PLMN，则AMF将以相应的原因值来拒绝NGSetup过程。
2.NG SETUP信令结构
2.1 NG SETUP REQUEST结构
IE/Group Name |
Presence |
Range |
IE type and reference |
Semantics description |
Criticality |
Assigned Criticality |
Message Type |
M |
9.3.1.1 |
YES |
reject |
||
Global RAN Node ID |
M |
9.3.1.5 |
YES |
reject |
||
RAN Node Name |
O |
PrintableString (SIZE(1..150, …)) |
YES |
ignore |
||
Supported TA List |
1 |
Supported TAs in the NG-RAN node. |
YES |
reject |
||
>Supported TA Item |
1..<maxnoof TACs> |
- |
||||
>>TAC |
M |
9.3.3.10 |
Broadcast TAC |
- |
||
>>Broadcast PLMN List |
1 |
- |
||||
>>>Broadcast PLMN Item |
1..<maxnoof BPLMNs> |
- |
||||
>>>>PLMN Identity |
M |
9.3.3.5 |
Broadcast PLMN |
- |
||
>>>>TAI Slice Support List |
M |
Slice Support List 9.3.1.17 |
Supported S-NSSAIs per TAC, per PLMN or per SNPN. |
- |
||
>>>>NPN Support |
O |
9.3.3.44 |
If the NID IE is included, it identifies a SNPN together with the PLMN Identity IE. |
YES |
reject |
|
>>>>Extended TAI Slice Support List |
O |
Extended Slice Support List 9.3.1.191 |
Additional Supported S-NSSAIs per TAC, per PLMN or per SNPN. |
YES |
reject |
|
>>Configured TAC Indication |
O |
9.3.3.50 |
YES |
ignore |
||
>>RAT Information |
O |
9.3.1.125 |
RAT information associated with the TAC of the indicated PLMN(s). |
YES |
reject |
|
Default Paging DRX |
M |
Paging DRX 9.3.1.90 |
YES |
ignore |
||
UE Retention Information |
O |
9.3.1.117 |
YES |
ignore |
||
NB-IoT Default Paging DRX |
O |
9.3.1.137 |
YES |
ignore |
||
Extended RAN Node Name |
O |
9.3.1.193 |
YES |
ignore |
2.2 NG SETUP RESPONSE结构
IE/Group Name |
Presence |
Range |
IE type and reference |
Semantics description |
Criticality |
Assigned Criticality |
Message Type |
M |
9.3.1.1 |
YES |
reject |
||
AMF Name |
M |
9.3.3.21 |
YES |
reject |
||
Served GUAMI List |
1 |
YES |
reject |
|||
>Served GUAMI Item |
1..<maxnoof ServedGUAMIs> |
- |
||||
>>GUAMI |
M |
9.3.3.3 |
- |
|||
>>Backup AMF Name |
O |
AMF Name 9.3.3.21 |
- |
|||
>>GUAMI Type |
O |
ENUMERATED (native, mapped, …) |
YES |
ignore |
||
Relative AMF Capacity |
M |
9.3.1.32 |
YES |
ignore |
||
PLMN Support List |
1 |
YES |
reject |
|||
>PLMN Support Item |
1..<maxnoof PLMNs> |
- |
||||
>>PLMN Identity |
M |
9.3.3.5 |
- |
|||
>>Slice Support List |
M |
9.3.1.17 |
Supported S-NSSAIs per PLMN or per SNPN. |
- |
||
>>NPN Support |
O |
9.3.3.44 |
If NID IE is included, it identifies a SNPN together with the PLMN Identity IE. |
YES |
reject |
|
>>Extended Slice Support List |
O |
9.3.1.191 |
Additional Supported S-NSSAIs per PLMN or per SNPN. |
YES |
reject |
|
>>Onboarding Support |
O |
ENUMERATED (true, ...) |
Indication of onboarding support. |
YES |
ignore |
|
Criticality Diagnostics |
O |
9.3.1.3 |
YES |
ignore |
||
UE Retention Information |
O |
9.3.1.117 |
YES |
ignore |
||
IAB Supported |
O |
ENUMERATED (true, ...) |
Indication of support for IAB. |
YES |
ignore |
|
Extended AMF Name |
O |
9.3.3.51 |
YES |
ignore |
Range bound |
Explanation |
maxnoofServedGUAMIs |
Maximum no. of GUAMIs served by an AMF. Value is 256. |
maxnoofPLMNs |
Maximum no. of PLMNs per message. Value is 12. |
2.3 NG SETUP FAILURE结构
IE/Group Name |
Presence |
Range |
IE type and reference |
Semantics description |
Criticality |
Assigned Criticality |
Message Type |
M |
9.3.1.1 |
YES |
reject |
||
Cause |
M |
9.3.1.2 |
YES |
ignore |
||
Time to Wait |
O |
9.3.1.56 |
YES |
ignore |
||
Criticality Diagnostics |
O |
9.3.1.3 |
YES |
ignore |
