# EPS Mobility Management (EMM) / EPS移动性管理

## 定义 / Definition

### English Mobility management protocol for EPS (Evolved Packet System), also known as LTE. EMM handles UE registration, authentication, tracking area management, and security mode procedures.

### 中文 EPS(演进分组系统,也称为LTE)的移动性管理协议。EMM处理UE注册、认证、跟踪区域管理和安全模式流程。

## EMM 流程 / EMM Procedures

### English

流程描述 ------------ AttachInitial network registration DetachNetwork deregistration TAU (Tracking Area Update)Update UE location Service RequestRespond to paging AuthenticationVerify UE identity Security Mode CommandActivate ciphering

### 中文

流程描述 ------------ Attach初始网络注册 Detach网络注销 TAU (跟踪区更新)更新UE位置 Service Request响应寻呼 Authentication验证UE身份 Security Mode Command激活加密

## EMM 状态 / EMM States

+----------+     +----------+     +----------+
EMM-DEREGISTERED-->EMM-REGISTERED
(未注册)(已注册)
+----------+     +----------+     +----------+
                           |
                           v
                    +------------+
                    EMM-CONTACT
                    (已连接)
                    +------------+

## 交叉引用 / Cross References

- TS 24.301 - EMM specification - TS 23.401 - EPS architecture - NAS - Mobility Management - ESM