GB28181-注销

发起注销和发起注册区别在于 Expires: 0，发起注册Expires: 的值大于0，而注销则是0

发送注销

相机配置GB28181开启后，相机就会发送sip消息包到相应的sip-server

REGISTER sip:41010500002000000001@4101050000 SIP/2.0
Via: SIP/2.0/UDP 192.168.1.70:5060;rport;branch=z9hG4bK452554307
From: <sip:32000004561321000011@4101050000>;tag=1763913758
To: <sip:32000004561321000011@4101050000>
Call-ID: 745693128
CSeq: 1 REGISTER
Contact: <sip:32000004561321000011@192.168.1.70:5060>
Max-Forwards: 70
User-Agent: IP Camera
Expires: 0
Content-Length: 0

回复401

机就会发送sip消息包到相应的sip-server，sip-server会回复401消息
注意：WWW-Authenticate 这个消息头会告诉algorithm=MD5，加密算法采用具体哪种加密算法，取值为 MD5/SHA-1/
SHA-256中其中一种，大多数都是采用MD5

SIP/2.0 401 Unauthorized
CSeq: 1 REGISTER
Call-ID: 745693128
From: <sip:32000004561321000011@4101050000>;tag=1763913758
To: <sip:32000004561321000011@4101050000>
Via: SIP/2.0/UDP 192.168.1.70:5060;rport=5060;branch=z9hG4bK452554307;received=192.168.1.70
WWW-Authenticate: Digest realm="4101050000",qop="auth",nonce="3dfa3de4dd8a23c265efa97cd9dbef81",algorithm=MD5
Content-Length: 0

二次注册

根据上面回复401进行组装Authorization，发送第二次注销消息

REGISTER sip:41010500002000000001@4101050000 SIP/2.0
Via: SIP/2.0/UDP 192.168.1.70:5060;rport;branch=z9hG4bK2114466735
From: <sip:32000004561321000011@4101050000>;tag=1763913758
To: <sip:32000004561321000011@4101050000>
Call-ID: 745693128
CSeq: 2 REGISTER
Contact: <sip:32028108951321000011@192.168.1.70:5060>
Authorization: Digest username="32000004561321000011", realm="4101050000", nonce="3dfa3de4dd8a23c265efa97cd9dbef81", uri="sip:41010500002000000001@4101050000", response="7ccaadb8a91ec822aaabb63800208d81", algorithm=MD5, cnonce="0a4f113b", qop=auth, nc=00000001
Max-Forwards: 70
User-Agent: IP Camera
Expires: 0
Content-Length: 0

注销成功

回复200 ok，注销成功

SIP/2.0 200 OK
CSeq: 2 REGISTER
Call-ID: 745693128
From: <sip:32000004561321000011@4101050000>;tag=1763913758
To: <sip:32000004561321000011@4101050000>
Via: SIP/2.0/UDP 192.168.1.70:5060;rport=5060;branch=z9hG4bK2114466735;received=192.168.1.70
Date: 2023-12-18T11:11:04.959
Contact: <sip:32028108951321000011@192.168.1.70:5060>
Expires: 3600
Content-Length: 0

密码错误

要是出现 403，说明密码错误。