在4G(LTE)無線網(wǎng)絡(luò)中終端與和網(wǎng)絡(luò)之間通過交換協(xié)議信息進行信息交互和數(shù)據(jù)傳遞，從而達到通信的目的。這些步驟中所有細節(jié)都可能對4G(LTE)的終端（UE)無線通信產(chǎn)生影響；整理：kangguoying20200817

1.終端業(yè)務(wù)標(biāo)準(zhǔn)流程圖

         LTE網(wǎng)絡(luò)中終端從開機到完成一次數(shù)據(jù)通信要經(jīng)過小區(qū)選擇、接入、認證鑒權(quán)、承載分配、測量配置等流程；整個過程可通過下圖予以概括；整理：kangguoying20200817

2.數(shù)據(jù)業(yè)務(wù)相關(guān)消息

          終端（UE)從開通到完成數(shù)據(jù)通信，期間在無線空口交互的消息大概有32條；這些消息涉及物理層、層三和高層（layer3)中的廣播消息、接入層（AS)和非接入層消息(NAS);具體消息如下：整理：kangguoying20200817

         1) <Cell Search and Detection>整理：kangguoying20200817

          2) MIB整理：kangguoying20200817

          3) SIB 1整理：kangguoying20200817

          4) <Check Cell Selection Criteria>

          5) SIB 2 and other SIBs整理：kangguoying20200817

          6) RRC : PRACH Preamble

          7) RRC : RACH Response整理：kangguoying20200817

          8) RRC : RRC Connection Request

          9) RRC : RRC Connection Setup

          10) RRC : RRC Connection Setup Complete + NAS : Attach Request + ESM : PDN Connectivity Request

          11) RRC : DL Information Transfer + NAS : Authentication Request

          12) RRC : UL Information Transfer + NAS : Authentication Response

          13) RRC : DL Information Transfer + NAS : Security Mode Command

          14) RRC : UL Information Transfer + NAS : Security Mode Complete

          15) RRC : Security M ode Command整理：kangguoying20200817

          16) RRC : Security Mode Complete

                    O1) RRC : UE Capability Enquiry整理：kangguoying20200817

                       O2) RRC : UE Capability Information

                       O3) ESM : ESM Information Request整理：kangguoying20200817

                       O4) ESM : ESM Information Response

                       O5) EMM : EMM Identity Request

                       O6) EMM : EMM Identity Response

          17) RRC : RRC Connection Reconfiguration + NAS : Attach Accept + NAS : Activate Default EPS Bearer Context Req

          18) RRC : RRC Connection Reconfiguration Complete + NAS : Attach Complete + NAS : Activate Default EPS Bearer Context Accept整理：kangguoying20200817

                     O7) EMM : EMM Information整理：kangguoying20200817

          19) RRC : RRC Connection Release

          20) <Perform Neibourcell Measurement>

          21) <Check Cell Reselection Criteria >整理：kangguoying20200817

          22) < MO or MT call > : In MT call, Paging should be sent.

          23) RRC : PRACH Preamble整理：kangguoying20200817

          24) RRC : RACH Response整理：kangguoying20200817

          25) RRC : RRC Connection Request

          26) RRC : RRC Connection Setup

          27) RRC : RRC Connection Setup Complete + NAS : Service Request

          28) RRC : Security Mode Command整理：kangguoying20200817

          29) RRC : Security Mode Complete整理：kangguoying20200817

          30) RRC : RRC Connection Reconfiguration + NAS : Activate Dedicated EPS Bearer Context Request

          31) RRC : RRC Connection Reconfiguration Complete + NAS : Activate Dedicated EPS Bearer Context Accept

          32) RRC : RRC Connection Release整理：kangguoying20200817

3.業(yè)務(wù)消息承載信道

          在無線網(wǎng)絡(luò)中終端與網(wǎng)絡(luò)之間的信息通過信道來傳遞傳遞，期間分別通過PDCP層、RLC層和MAC層進行加密壓縮、調(diào)度編排；通過廣播信道、共享信道進行傳遞；終端進行數(shù)據(jù)業(yè)務(wù)中涉及相關(guān)信道見下表：整理：kangguoying20200817

原文來自：http://www.sharetechnote.com/  整理：kangguoying20200817

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