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一.Ims 注册
1、DS 通知 IMS,LTE 的服务是可用的,主要搜索关键字 pref_rat_value = 3 and RAT =
10 ,等于 3 代表为 LTE
Sipconnection.cpp 包括一些请求消息的查询
2、IMS 获得 APN 列表,属性等消息,比如 apntype = 1 ,apnname = ims 等。
3、DS 触发 PDN CONNREQ,然后触发 IMS 注册,搜索关键字 IMS_REG_STATUS_IND
4、发送 sip 注册消息。 EVENT_SIP_REG_REQ_SENT
5、通知 CM IMS 注册状态变化,set ims voice reg_status 2 on mode9
二、IMS MO CALL 针对 SIP 信令的分析
1、首先会发送一条 IMS_SIP_INVITE/INFORMAL_RESPONSE,主要消息内容:
Subscription ID = 2
Version = 1
Direction = UE_TO_NETWORK //代表手机发送到网络
SDP Presence = 1
SIP Call ID Length = 59
SIP Message Length = 2243
SIP Message Logged Bytes = 2244
Message ID = IMS_SIP_INVITE //这条信令的名称
Response Code = INFORMAL_RESPONSE (0)
CM Call ID = 10
SIP Call ID = 4135808202_467862876@2408:850c:ff:498b:43c7:c24e:99e3:b6d0 //代表此次回话的表示 ID,整个流程中不会改变
Sip Message = INVITE tel:13167010170;phone-context=ims.mnc001.mcc460.3gppnetwork.org SIP/2.0
From: <sip:+8618616378362@sh.ims.mnc001.mcc460.3gppnetwork.org>;tag=4135808209 //主叫方
To: <tel:13167010170;phone-context=ims.mnc001.mcc460.3gppnetwork.org> //被叫方