设备注册（REGISTER）- 未认证 → 认证通过
1. IPC向平台注册过程，注册主要是两次交互：
第一个交互：IPC向平台发送请求注册，平台回复unanthorized要求前端带上鉴权信息再次注册；
第二个交互：IPC带上鉴权信息重新想平台发送注册请求，平台经过校验成功后返回200 OK 完成注册。
协议信息
第一次注册（未携带认证信息，返回401） REGISTER sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK999789587 From: <sip:31000000001120000145@3100000000>;tag=1549485542 To: <sip:31000000001120000145@3100000000> Call-ID: 1390477598 CSeq: 1 REGISTER Contact: <sip:31000000001120000145@10.10.10.239:5060> Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Expires: 3600 Content-Length: 0#平台响应（401 Unauthorized）：返回Digest认证信息（realm、nonce） SIP/2.0 401 Unauthorized From: <sip:31000000001120000145@3100000000>;tag=1549485542 To: <sip:31000000001120000145@3100000000>;tag=c986910-20a0a0a-1587-a1fc7-42327bba-a1fc7 Call-ID: 1390477598 CSeq: 1 REGISTER WWW-Authenticate: Digest realm="31000000",nonce="6fe9b8c777dbe22a",algorithm=MD5 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Expires: 3600 Via: SIP/2.0/UDP 10.10.10.239:5060;rport=5060;branch=z9hG4bK999789587 Content-Length: 0
第二次注册（携带认证信息，返回200 OK） REGISTER sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK501702578 From: <sip:31000000001120000145@3100000000>;tag=1549485542 To: <sip:31000000001120000145@3100000000> Call-ID: 1390477598 CSeq: 2 REGISTER Contact: <sip:31000000001120000145@10.10.10.239:5060> Authorization: Digest username="admin", realm="31000000", nonce="6fe9b8c777dbe22a", uri="sip:31000000002000000000@3100000000", response="ea04f3ab3b5799384145becb915a9669", algorithm=MD5 Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Expires: 3600 Content-Length: 0平台响应（200 OK）：注册成功，返回设备注册响应XML SIP/2.0 200 OK From: <sip:31000000001120000145@3100000000>;tag=1549485542 To: <sip:31000000001120000145@3100000000>;tag=c98a6d0-20a0a0a-1587-a1fc7-1e5fe326-a1fc7 Call-ID: 1390477598 CSeq: 2 REGISTER Date: 2021-06-09T10:55:40 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Expires: 3600 Via: SIP/2.0/UDP 10.10.10.239:5060;rport=5060;branch=z9hG4bK501702578 Content-Type: application/MANSCDP+xml Content-Length: 373<?xml version="1.0" ?> <Response> <CmdType>Register</CmdType> <SN>0</SN> <DeviceID>31000000001120000145</DeviceID> <Result>OK</Result> <Manufacturer>Kedacom</Manufacturer> <ProtocolExtension> <ProtocolName>GB28181X</ProtocolName> <ExtensionName>Kedacom</ExtensionName> <Version> <Major>2</Major> <Minor>0</Minor> </Version> </ProtocolExtension> </Response>
平台发起命令交互
目录查询（MESSAGE + Catalog）
平台向NVR发送目录查询命令，获取下级设备列表 MESSAGE sip:31000000001120000145@3100000000 SIP/2.0 From: <sip:31000000002000000000@3100000000>;tag=c986df0-20a0a0a-1587-a1fc8-6e47bfa6-a1fc8 To: <sip:31000000001120000145@3100000000> Call-ID: c986df0-20a0a0a-1587-a1fc8-61ea7427-a1fc8@3100000000 CSeq: 522698020 MESSAGE Via: SIP/2.0/UDP 10.10.10.2:5511;rport;branch=z9hG4bK-a1fc8-278c2543-731b9437 User-Agent: Kedacom Max-Forwards: 70 Content-Type: application/MANSCDP+xml Content-Length: 128 <?xml version="1.0" ?> <Query> <CmdType>Catalog</CmdType> <SN>471</SN> <DeviceID>31000000001120000145</DeviceID> </Query>NVR响应目录查询结果，返回关联的IPC设备信息 MESSAGE sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK1562266673 From: <sip:31000000001120000145@3100000000>;tag=1189068873 To: <sip:31000000002000000000@3100000000> Call-ID: 898694010 CSeq: 3 MESSAGE Content-Type: application/MANSCDP+xml Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Content-Length: 715 <?xml version="1.0"?> <Response> <CmdType>Catalog</CmdType> <SN>471</SN> <DeviceID>31000000001120000145</DeviceID> <SumNum>1</SumNum> <DeviceList Num="1"> <Item> <DeviceID>31000000001320000146</DeviceID> <Name>FPDLINK-0</Name> <Manufacturer>KEDACOM</Manufacturer> <Model>IPC186-PCWS</Model> <Owner></Owner> <CivilCode></CivilCode> <Block></Block> <Address></Address> <Parental>0</Parental> <ParentID>31000000001120000145</ParentID> <SafetyWay>0</SafetyWay> <RegisterWay>1</RegisterWay> <Secrecy>0</Secrecy> <IPAddress>10.10.10.239</IPAddress> <Port>5060</Port> <Status>ON</Status> <Longitude>0.000000</Longitude> <Latitude>0.000000</Latitude> <Info> <SourceID>0</SourceID> </Info> </Item> </DeviceList> </Response>
报警订阅与查询（SUBSCRIBE + MESSAGE）
平台订阅NVR报警状态，并发送报警查询命令 SUBSCRIBE sip:31000000001120000145@3100000000 SIP/2.0 From: <sip:31000000002000000000@3100000000>;tag=c981150-20a0a0a-1587-a1fc8-547394c0-a1fc8 To: <sip:31000000001120000145@3100000000> Call-ID: cb4e858-20a0a0a-1587-a1fc8-15f4212c-a1fc8@3100000000 CSeq: 1 SUBSCRIBE Via: SIP/2.0/UDP 10.10.10.2:5511;rport;branch=z9hG4bK-a1fc8-278c254e-19ec1512 Expires: 3600 Event: Catalog User-Agent: Kedacom Max-Forwards: 70 Contact: <sip:31000000002000000000@10.10.10.2:5511> Content-Type: application/MANSCDP+xml Content-Length: 156 <?xml version="1.0" ?> <Query> <CmdType>Alarm</CmdType> <SN>472</SN> <DeviceID>31000000001120000145</DeviceID> <AlarmMethod>0</AlarmMethod> </Query>NVR响应报警查询结果（状态正常） SIP/2.0 200 OK Via: SIP/2.0/UDP 10.10.10.2:5511;rport=5511;branch=z9hG4bK-a1fc8-278c254e-19ec1512 From: <sip:31000000002000000000@3100000000>;tag=c981150-20a0a0a-1587-a1fc8-547394c0-a1fc8 To: <sip:31000000001120000145@3100000000>;tag=874656760 Call-ID: cb4e858-20a0a0a-1587-a1fc8-15f4212c-a1fc8@3100000000 CSeq: 1 SUBSCRIBE Contact: <sip:31000000001120000145@10.10.10.239:5060> Content-Type: application/MANSCDP+xml Event: Catalog User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Expires: 3600 Content-Length: 145 <?xml version="1.0"?> <Response> <CmdType>Alarm</CmdType> <SN>472</SN> <DeviceID>31000000001120000145</DeviceID> <Result>OK</Result> </Response>
设备心跳（MESSAGE + Keepalive）
MESSAGE sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK1899244551 From: <sip:31000000001120000145@3100000000>;tag=943197749 To: <sip:31000000002000000000@3100000000> Call-ID: 526458832 CSeq: 2 MESSAGE Content-Type: application/MANSCDP+xml Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Content-Length: 146 <?xml version="1.0"?> <Notify> <CmdType>Keepalive</CmdType> <SN>1797</SN> <DeviceID>31000000001120000145</DeviceID> <Status>OK</Status> </Notify>
设备能力查询（MESSAGE + Capability）
MESSAGE sip:31000000001120000145@3100000000 SIP/2.0 From: <sip:31000000002000000000@3100000000>;tag=c970050-20a0a0a-1587-a1fc8-1133733a-a1fc8 To: <sip:31000000001120000145@3100000000> Call-ID: c970050-20a0a0a-1587-a1fc8-2f7485af-a1fc8@3100000000 CSeq: 714439893 MESSAGE Via: SIP/2.0/UDP 10.10.10.2:5511;rport;branch=z9hG4bK-a1fc8-278c2814-79c2fb04 User-Agent: Kedacom Max-Forwards: 70 Content-Type: application/MANSCDP+xml Content-Length: 211 <?xml version="1.0" ?> <Query> <CmdType>KdmCapability</CmdType> <SN>473</SN> <DeviceID>31000000001120000145</DeviceID> <KdmCapability> <StringItem Name="MRTC" Value="false" /> </KdmCapability> </Query>NVR返回扩展能力详情（GPS、GB_OSD、回放速度等） MESSAGE sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK2023610586 From: <sip:31000000001120000145@3100000000>;tag=185590141 To: <sip:31000000002000000000@3100000000> Call-ID: 1436817154 CSeq: 4 MESSAGE Content-Type: application/MANSCDP+xml Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Content-Length: 398 <?xml version="1.0"?> <Response> <CmdType>KdmCapability</CmdType> <SN>473</SN> <DeviceID>31000000001120000145</DeviceID> <Result>OK</Result> <KdmCapability> <StringItem Name="GPS" Value="false" /> <StringItem Name="GB_OSD" Value="true" /> <StringItem Name="MaxReplaySpeed" Value="16" /> <StringItem Name="SRTP" Value="false" /> <StringItem Name="MRTC" Value="false" /> </KdmCapability> </Response>
IPC配置查询（MESSAGE + ConfigDownload）
平台向IPC（31000000001320000146）发送4类配置查询命令，分别为视频参数选项、视频参数配置、视频输入参数、视频编码配置，以下为核心交互示例：1. 视频参数选项查询（平台→IPC） MESSAGE sip:31000000001320000146@3100000000 SIP/2.0 From: <sip:31000000002000000000@3100000000>;tag=c972750-20a0a0a-1587-a1fc9-2dbba1ef-a1fc9 To: <sip:31000000001320000146@3100000000> Call-ID: c972750-20a0a0a-1587-a1fc9-50a5c108-a1fc9@3100000000 CSeq: 1834616561 MESSAGE Via: SIP/2.0/UDP 10.10.10.2:5511;rport;branch=z9hG4bK-a1fc9-278c2933-53db2b4c User-Agent: Kedacom Max-Forwards: 70 Content-Type: application/MANSCDP+xml Content-Length: 175<?xml version="1.0" ?> <Query> <CmdType>ConfigDownload</CmdType> <SN>474</SN> <DeviceID>31000000001320000146</DeviceID> <ConfigType>VideoParamOpt</ConfigType> </Query>2. 视频参数选项响应（IPC→平台，通过NVR转发） MESSAGE sip:31000000002000000000@3100000000 SIP/2.0 Via: SIP/2.0/UDP 10.10.10.239:5060;rport;branch=z9hG4bK50183248 From: <sip:31000000001120000145@3100000000>;tag=1929370178 To: <sip:31000000002000000000@3100000000> Call-ID: 221896874 CSeq: 5 MESSAGE Content-Type: application/MANSCDP+xml Max-Forwards: 70 User-Agent: Kedacom NVR/7.0 GB28181X/Kedacom3.0 Content-Length: 525 <?xml version="1.0"?> <Response> <CmdType>ConfigDownload</CmdType> <SN>474</SN> <DeviceID>31000000001320000146</DeviceID> <Result>OK</Result> <VideoParamOpt> <VideoFormatOpt>2/MJPEG/H265</VideoFormatOpt> <ResolutionOpt>5/1280x960/1600x1200/6/2560x1440/2592x1944/2560x1920/2592x1520/3840x2160/3072x2048</ResolutionOpt> <FrameRateOpt>60</FrameRateOpt> <BitRateTypeOpt>2</BitRateTypeOpt> <VideoBitRateOpt>16384</VideoBitRateOpt> <DownloadSpeedOpt>1/2/4/8/16/0.5/0.25/0.125/0.0625</DownloadSpeedOpt> </VideoParamOpt> </Response>
SIP协议注册过程虽然成功了，但
CU需要等到catalog和订阅的alarm信息成功后才会上线；
NVR要invite请求前端视频成功后才会上线。
上线失败原因1：
有时注册平台时，前端显示已注册成功，但CU上前端却不上线，抓包看注册流程也没有什么错误，查到最后才发现是通道ID没有填写。仔细看catalog内容DeviceID内容是空的。
上线失败原因2：
35114注册成功，但平台端上IPC不上线，可能之一如下图，两者时间相差超过了阈值
阶段2：平台发起命令交互（MESSAGE/SUBSCRIBE）
其他过程待后续有时间再补充
2. 注销（取消注册）
与注册相同的地方：流程上一模一样，都是（1）前端发REGISTER，（2）平台回401，（3）设备再发REGISTER,（4）平台回200ok。 与注册不同的地方： 区别1：注册时四个步骤中Expires=“续租时间”，注销时Expires=0； 区别2：第四步注册时有messagebody，注销时不需要携带messagebody。
