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目录

1. Attach(23.401 5.3.2)

2. Service Request(23.401 5.3.4)

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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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

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