NAS协议解读.doc

1、 NAS消息类型：EPS mobility management message types和EPS session management message types（24301-a10（230页）。2、 根据协议指示判断是移动性管理消息和会话管理消息: Protocol discriminator（24007-900（100页）if（pd=2）会话管理消息解码（8.3节）else if（pd=7）移动性管理消息解码（8.2节）3、 移动性管理消息解码：u 协议指示（Protocol discriminator）+安全头（Security header type）：1字节u 消息类型（Message type）：1字节u 其他字段解码。4、 会话管理消息解码：u 协议指示（Protocol discriminator）+承载ID（EPS bearer identity）：1字节u 过程事务ID（Procedure transaction identity）：1字节u 消息类型（Message type）：1字节u 其他字段解码。注1：TLV（标志，长度，值）注2：O：可选部分；M：必选固定；C：条件可选。Table 9.8.1: Message types for EPS mobility managementBits8765432101-EPS mobility management messages01000001Attach request01000010Attach accept01000011Attach complete01000100Attach reject01000101Detach request01000110Detach accept01001000Tracking area update request01001001Tracking area update accept01001010Tracking area update complete01001011Tracking area update reject01001100Extended service request01001110Service reject01010000GUTI reallocation command01010001GUTI reallocation complete01010010Authentication request01010011Authentication response01010100Authentication reject01011100Authentication failure01010101Identity request01010110Identity response01011101Security mode command01011110Security mode complete01011111Security mode reject01100000EMM status01100001EMM information01100010Downlink NAS transport01100011Uplink NAS transport01100100CS Service notification01101000Downlink generic NAS transport01101001Uplink generic NAS transportTable 9.8.2: Message types for EPS session managementBits8765432111-EPS session management messages11000001Activate default EPS bearer context request11000010Activate default EPS bearer context accept11000011Activate default EPS bearer context reject11000101Activate dedicated EPS bearer context request11000110Activate dedicated EPS bearer context accept11000111Activate dedicated EPS bearer context reject11001001Modify EPS bearer context request11001010Modify EPS bearer context accept11001011Modify EPS bearer context reject11001101Deactivate EPS bearer context request11001110Deactivate EPS bearer context accept11010000PDN connectivity request11010001PDN connectivity reject11010010PDN disconnect request11010011PDN disconnect reject11010100Bearer resource allocation request11010101Bearer resource allocation reject11010110Bearer resource modification request11010111Bearer resource modification reject11011001ESM information request11011010ESM information response11011011Notification11101000ESM status