"Session Management (SM)

## 定义 / Definition

### English Functions for managing packet data sessions, including PDP (Packet Data Protocol) context activation, modification, deactivation, and QoS (Quality of Service) negotiation.

### 中文 用于管理分组数据会话的功能，包括PDP（分组数据协议）上下文激活、修改、去激活和QoS（服务质量）协商。

## SM 流程 / SM Procedures

### English

流程描述 ------------ PDP Context ActivationEstablish data connection PDP Context ModificationChange QoS parameters PDP Context DeactivationRelease data connection Secondary PDP ContextAdditional bearer

### 中文

流程描述 ------------ PDP上下文激活建立数据连接 PDP上下文修改更改QoS参数 PDP上下文去激活释放数据连接 次级PDP上下文额外承载

## PDN 连接 / PDN Connection

UE <-> SGW <-> PGW <-> Internet
   
   +---PDP Context---+

## 消息 / Messages

消息方向描述 ------------------ ACTIVATE PDP CONTEXT REQUESTMS → SGSN激活请求 ACTIVATE PDP CONTEXT ACCEPTSGSN → MS激活接受 MODIFY PDP CONTEXT REQUESTMS/SGSN → SGSN/MS修改请求 DEACTIVATE PDP CONTEXT REQUESTMS/SGSN → SGSN/MS去激活请求

## 交叉引用 / Cross References

- TS 24.008 - SM procedures - TS 24.301 - EPS Session Management - TS 24.501 - 5G PDU Session - GMM