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目录

Attach(23.401%205.3.2)-toc" style="margin-left:0px;">1. Attach(23.401 5.3.2)

2. Service Request(23.401 5.3.4)

TAU%20(23.401%205.3.3)-toc" style="margin-left:0px;">3. TAU (23.401 5.3.3)

3.1 Tracking Area Update procedure with Serving GW change

 3.2 Tracking Area Update procedure without Serving GW change

4. Detach

4.1 UE-initiated Detach procedure

4.2 MME-initiated Detach procedure

4.3 HSS-initiated Detach procedure

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Attach(23.401%205.3.2)" style="background-color:transparent;text-align:justify;">1. Attach(23.401 5.3.2)

信令	接口	可选	字段	可选	注释
Attach request	S1-MME	M	guti/imsi	M	UE没有保存guti时，使用imsi附着;UE保存了老的guti，则使用guti附着。Guti附着还是imsi附着，在type of identity字段中定义。
			Additional guti	O	Old guti是从P-TMSI映射的值的时候，该guti并不是MME分配的guti，此时包里带Additional guti，additional guti才是MME分配的guti
			LAI	O	位置信息
Identification Request/Response	S10/S3
Identity Request	S1-MME	O（MME找不到老的UE信息时，向UE请求imsi）	Identity type	M	Identity类型
Identity Response	S1-MME	O	Guti/imsi	M	返回的identity
Authentication Information Request/Response	S6a	O			当前的HSS中没有该用户的鉴权信息时，发起鉴权过程，S6A的包中会包含rand和key
Authentication Request	S1-MME	O	KSI	M
			RAND
Authentication Response	S1-MME	O
Security Mode Command	S1-MME	O	NAS security algorithms	M	更新加密算法
			KSI
Security Mode Complete	S1-MME	O	IMEISV	O	如果cmd中有IMEISV request，则complete中必须携带IMEISV。
					此包开始用新的密钥加密，security header type为4，凭此判断更新密钥，并用新的密钥解密
Create Session Request	S11	M	IMSI	C
			MEI	C
			MSISDN	C
Create Session  Response	S11	M	cause
			Sender F-TEID for Control Plane
Initial Context Setup Request/Attach accept	S1-MME	M	ERAB-ID	M
			TEID/IP	M
			MME UE S1AP ID 2	O	This IE indicates the MME UE S1AP ID assigned by the MME.
			GUTI	O	NAS中,attach accept消息携带
			Location area identification	O	NAS中，attach accept消息携带
Initial Context Setup Request	S1-MME	M	ERAB-ID	M
			TEID/IP	M
Attach Complete	S1-MME	M
Modify Bearer Request	S11	M	MEI	C
			Serving Network	CO
						Modify Bearer Response	S11	M	Cause
MSISDN
Linked EPS Bearer ID

2. Service Request(23.401 5.3.4)

信令	接口	可选	字段	可选	注释
Initial UE Message /Service request	S1-MME	M	S_TMSI	M	值同guti，可用于关联老的流
			Additional guti	O	Old guti是从P-TMSI映射的值的时候，该guti并不是MME分配的guti，此时包里带Additional guti，additional guti才是MME分配的guti
			LAI	O	位置信息
Authentication Information Request/Response	S6a	O			当前的HSS中没有该用户的鉴权信息时，发起鉴权过程，S6A的包中会包含rand和key
Authentication Request	S1-MME	O	KSI	M
			RAND
Authentication Response	S1-MME	O
Security Mode Command	S1-MME	O	NAS security algorithms	M	更新加密算法
			KSI
Security Mode Complete	S1-MME	O	IMEISV	O	如果cmd中有IMEISV request，则complete中必须携带IMEISV。
					此包开始用新的密钥加密，security header type为4，凭此判断更新密钥，并用新的密钥解密
Initial Context Setup Request	S1-MME	M	ERAB-ID	M
Initial Context Setup Response
Initial Context Setup Complete
Modify Bearer Request	S11	M	MEI	C
			Serving Network	CO
						Modify Bearer Response	S11	M	Cause
			MSISDN
			Linked EPS Bearer ID

TAU%20(23.401%205.3.3)" style="text-align:justify;">3. TAU (23.401 5.3.3)

3.1 Tracking Area Update procedure with Serving GW change

信令	接口	可选	字段	可选	注释
TAU request	S1-MME	M	Old_guti	M	值同guti，可用于关联老的流
			Additional guti	O	Old guti是从P-TMSI映射的值的时候，该guti并不是MME分配的guti，此时包里带Additional guti，additional guti才是MME分配的guti
			Old_LAI	O	位置信息
Create Session Request	S11	M	IMSI	C
			MEI	C
			MSISDN	C
Modify Bearer Request	S11	M	MEI	C
			Serving Network	CO
						Modify Bearer Response	S11	M	Cause
Create Session  Response	S11	M	cause
Delete session request	S11
TAU accept	S1-MME		guti
			lac
Delete session response	S11
TAU complete	S1-MME	O

 3.2 Tracking Area Update procedure without Serving GW change

4. Detach

4.1 UE-initiated Detach procedure

4.2 MME-initiated Detach procedure

4.3 HSS-initiated Detach procedure