5G UDM订阅数据管理Nudm_SDM四服务信令全链路拆解

graph LR
    subgraph UDM数据资源层级
        A["/{supi}"] --> B["/am-data<br/>接入与移动性数据"]
        A --> C["/smf-select-data<br/>SMF选择数据"]
        A --> D["/sm-data<br/>会话管理数据"]
        A --> E["/ue-context-in-smf-data<br/>SMF中的UE上下文"]
        A --> F["/sms-data<br/>SMS签约数据"]
        A --> G["/sdm-subscriptions<br/>订阅关系"]
    end

    subgraph 消费者NF
        AMF["AMF"] -->|Get am-data| B
        AMF -->|Get smf-select-data| C
        AMF -->|Get ue-context-in-smf-data| E
        SMF["SMF"] -->|Get sm-data| D
        SMSF["SMSF"] -->|Get sms-data| F
    end

    AMF -->|Subscribe| G
    SMF -->|Subscribe| G
    UDM["UDM"] -->|Notification 回调| AMF
    UDM -->|Notification 回调| SMF

sequenceDiagram
    participant UE
    participant RAN
    participant NewAMF as 新AMF
    participant OldAMF as 旧AMF
    participant UDM
    participant UDR

    Note over UE,UDM: TS 23.502 Section 4.2.2.2 步骤13-14

    UE->>RAN: Registration Request(SUCI/5G-GUTI)
    RAN->>NewAMF: N2 Initial UE Message + NAS

    opt 旧AMF存在（步骤5-10）
        NewAMF->>OldAMF: Namf_Communication_UEContextTransfer
        OldAMF-->>NewAMF: 200 OK(含已缓存的签约数据)
    end

    rect rgb(230, 245, 255)
    Note right of NewAMF: 步骤13: AMF选择UDM实例
    Note right of NewAMF: 若SUCI加密则先经SIDF解密

    NewAMF->>UDM: 14a. GET /nudm-sdm/v2/{supi}/am-data
    Note right of NewAMF: Query: fields=<过滤字段><br/>Header: Accept: application/json
    UDM->>UDR: Nudr_DM_Query(GET /subscription-data/{supi}/am-data)
    UDR-->>UDM: 200 OK(AccessAndMobilitySubscriptionData)
    UDM-->>NewAMF: 200 OK(JSON Body)

    NewAMF->>UDM: 14a'. GET /nudm-sdm/v2/{supi}/smf-select-data
    UDM-->>NewAMF: 200 OK(SmfSelectionSubscriptionData)

    NewAMF->>UDM: 14a''. GET /nudm-sdm/v2/{supi}/ue-context-in-smf-data
    Note right of NewAMF: 获取已建立PDU会话的SMF信息
    UDM-->>NewAMF: 200 OK(UeContextInSmfData)

    NewAMF->>UDM: 14b. POST /nudm-sdm/v2/{supi}/sdm-subscriptions
    Note right of NewAMF: Body: SdmSubscription<br/>- nfInstanceId: AMF ID<br/>- callbackReference: URI<br/>- monitoredResourceUris<br/>- expiry: 订阅过期时间
    UDM-->>NewAMF: 201 Created(Location header + subscriptionId)
    end

    rect rgb(255, 240, 230)
    Note right of OldAMF: 步骤14d: 旧AMF取消订阅
    OldAMF->>UDM: DELETE /nudm-sdm/v2/{supi}/sdm-subscriptions/{subId}
    UDM-->>OldAMF: 204 No Content
    end

    NewAMF-->>RAN: Registration Accept
    RAN-->>UE: NAS Registration Accept

{
  "subscribedSnssaiInfos": {
    "00101": {
      "dnnSmfInfoList": [
        {
          "dnn": "internet",
          "smfInstaceId": "smf-instance-001"
        }
      ],
      "snssai": {"sst": 1, "sd": "000001"}
    }
  }
}

{
  "nfInstanceId": "550e8400-e29b-41d4-a716-446655440000",
  "callbackReference": "https://amf-01.example.com/nudm-sdm-notification/callback",
  "monitoredResourceUris": [
    "https://udm.example.com/nudm-sdm/v2/supi-imsi-460011234567890/am-data",
    "https://udm.example.com/nudm-sdm/v2/supi-imsi-460011234567890/smf-select-data"
  ],
  "expiry": "2026-12-31T23:59:59Z",
  "sdmSubscriptionId": "sub-20260524-001"
}

sequenceDiagram
    participant OAM as O&M系统
    participant UDR as UDR
    participant UDM as UDM
    participant AMF
    participant SMF
    participant UE

    Note over OAM,UE: TS 23.502 Section 4.2.2.2.2 订阅数据变更通知

    OAM->>UDR: 修改用户签约数据(如: 停机)
    UDR->>UDM: Nudr_DM_Notify(变更通知)
    Note right of UDR: UDR感知到数据变更<br/>通知已注册的UDM实例

    rect rgb(255, 245, 230)
    Note right of UDM: UDM查找SDM订阅表
    Note right of UDM: 遍历所有已订阅该SUPI的NF

    UDM->>AMF: POST {callbackUri}<br/>Nudm_SDM_Notification
    Note right of UDM: Body: ModificationNotification<br/>changeItems:[{op:REPLACE,<br/>path:/am-data/subscribedUeAmbr}]
    AMF-->>UDM: 200 OK(确认)
    end

    rect rgb(230, 255, 230)
    UDM->>SMF: POST {smfCallbackUri}<br/>Nudm_SDM_Notification
    Note right of UDM: Body: ModificationNotification<br/>changeItems:[{op:DELETE,<br/>path:/sm-data/dnnConfigurations/internet}]
    SMF-->>UDM: 200 OK(确认)
    end

    alt AMF判定需要去注册(如:停机)
        AMF->>UE: NAS Deregistration Request(type: re-registration required)
    else AMF判定仅需更新配置
        AMF->>UE: NAS UE Configuration Update Command
    end

    alt SMF判定需要释放会话
        SMF->>AMF: Nsmf_PDUSession_UpdateSMContext(释放指示)
        AMF->>UE: NAS PDU Session Release Command
    else SMF判定需要修改QoS
        SMF->>AMF: Nsmf_PDUSession_UpdateSMContext(QoS更新)
    end

{
  "notifyItems": [
    {
      "resourceId": "https://udm.example.com/nudm-sdm/v2/supi-imsi-460011234567890/am-data",
      "changeType": "MODIFY",
      "changeItems": [
        {
          "op": "REPLACE",
          "path": "/subscribedUeAmbr",
          "from": {"uplink": "1 Gbps", "downlink": "10 Gbps"},
          "to": {"uplink": "100 Mbps", "downlink": "1 Gbps"}
        }
      ]
    }
  ],
  "originalCallbackReference": "https://amf-01.example.com/nudm-sdm-notification/callback"
}

sequenceDiagram
    participant UE
    participant AMF
    participant SMF
    participant UDM
    participant PCF
    participant UPF

    UE->>AMF: NAS PDU Session Establishment Request
    AMF->>SMF: Nsmf_PDUSession_CreateSMContext

    rect rgb(240, 248, 255)
    Note right of SMF: TS 23.502 4.3.2.2.1 步骤7
    SMF->>UDM: GET /nudm-sdm/v2/{supi}/sm-data?dnn=internet&single-nssai={"sst":1}
    Note right of SMF: 查询特定DNN+S-NSSAI的会话管理数据
    UDM-->>SMF: 200 OK(SessionManagementSubscriptionData)
    Note right of UDM: 返回: dnnConfigurations,<br/>sscModes, 5gQosProfile,<br/>chargingProperties等

    SMF->>UDM: POST /nudm-sdm/v2/{supi}/sdm-subscriptions
    Note right of SMF: 订阅sm-data变更通知
    UDM-->>SMF: 201 Created
    end

    SMF->>PCF: Npcf_SMPolicyControl_Create
    SMF->>UPF: N4 Session Establishment
    SMF-->>AMF: Nsmf_PDUSession_CreateSMContext Response

时序保证：
1. 新AMF先执行 Nudm_UECM_Registration（注册自己为服务AMF）
2. 新AMF再执行 Nudm_SDM_Get + Subscribe
3. 旧AMF收到Nudm_SDM_Notification（告知AMF已变更）后，执行Unsubscribe
4. UDM维护subscription列表，新旧AMF的订阅短暂共存

graph TB
    subgraph NF消费者
        AMF["AMF"]
        SMF["SMF"]
        SMSF["SMSF"]
    end

    subgraph 数据管理层
        UDM_SDM["UDM<br/>Nudm_SDM服务"]
        UDM_UECM["UDM<br/>Nudm_UECM服务"]
        UDM_Auth["UDM<br/>Nudm_Auth服务"]
    end

    subgraph 数据存储层
        UDR["UDR<br/>Nudr_DM服务"]
    end

    subgraph 外部系统
        OAM["O&M/Provisioning"]
    end

    AMF -->|"Get/Subscribe<br/>am-data, smf-select-data"| UDM_SDM
    SMF -->|"Get/Subscribe<br/>sm-data"| UDM_SDM
    SMSF -->|"Get/Subscribe<br/>sms-data"| UDM_SDM

    AMF -->|"Registration<br/>服务AMF记录"| UDM_UECM
    SMF -->|"Registration<br/>PDU会话记录"| UDM_UECM

    UDM_SDM -->|"Nudr_DM_Query"| UDR
    UDM_SDM -->|"Nudr_DM_Subscribe"| UDR
    UDM_UECM -->|"Nudr_DM_Create/Update"| UDR

    UDM_SDM -->|"Nudm_SDM_Notification"| AMF
    UDM_SDM -->|"Nudm_SDM_Notification"| SMF

    OAM -->|"修改签约数据"| UDR
    UDR -->|"Nudr_DM_Notify"| UDM_SDM

    style UDR fill:#fff3e0
    style UDM_SDM fill:#e3f2fd
    style OAM fill:#f3e5f5

{nudm-sdm API Root}/v2
├── /{supi}
│   ├── /am-data                          → AMF获取移动性数据
│   ├── /smf-select-data                  → AMF获取SMF选择数据
│   ├── /ue-context-in-smf-data           → AMF获取PDU会话上下文
│   ├── /sm-data                          → SMF获取会话管理数据
│   │   ├── ?dnn=internet                 → 按DNN过滤
│   │   └── ?single-nssai={"sst":1}      → 按S-NSSAI过滤
│   ├── /sms-data                         → SMSF获取SMS数据
│   ├── /sms-mng-data                     → SMSF获取SMS管理数据
│   ├── /trace-data                       → 获取MDT追踪数据
│   ├── /sdm-subscriptions                → 订阅管理
│   │   ├── POST (创建订阅)
│   │   └── /{subscriptionId}
│   │       └── DELETE (取消订阅)
│   └── /lcs-pos-data                     → 位置服务数据
├── /shared-data                          → 共享数据
│   └── /{sharedDataId}
└── /{gpsi}                               → 外部标识符查询
    └── /sm-data

# 过滤所有Nudm_SDM消息
http2.headers.path contains "nudm-sdm"

# 过滤AMF获取移动性数据
http2.headers.path contains "nudm-sdm" and http2.headers.path contains "am-data"

# 过滤订阅操作
http2.headers.path contains "sdm-subscriptions" and http2.request.method == "POST"

# 过滤通知回调
http2.request.method == "POST" and http2.headers.path contains "callback"