Ngexesha lokugqibela sathetha ngeempawu zomgangatho omtsha we-NB-IoT ukusuka kwindawo yokujonga ulwakhiwo lwerediyo yokufikelela kwinethiwekhi. Namhlanje siza kuxoxa ngento etshintshileyo kwiNethiwekhi yeCore phantsi kwe-NB-IoT. Ngoko, masihambe.
Kubekho utshintsho olubalulekileyo kumbindi wothungelwano. Masiqale ngento yokuba into entsha ivele, kunye nenani leendlela, ezichazwa ngumgangatho njenge "CIoT EPS Optimization" okanye ukwenziwa ngcono kwenethiwekhi engundoqo ye-Intanethi yezinto.
Njengoko uyazi, kwiinethiwekhi eziphathwayo kukho iindlela ezimbini zonxibelelwano eziphambili, ezibizwa ngokuba yi-Control Plane (CP) kunye ne-User Plane (UP). I-Control Plane ijoliswe kutshintshiselwano lwemiyalezo yenkonzo phakathi kwezinto ezahlukeneyo zenethiwekhi kwaye isetyenziselwa ukuqinisekisa ukuhamba (ulawulo lokuhamba) lwezixhobo (UE) kunye nokuseka / ukugcina iseshoni yokuhanjiswa kwedatha (uLawulo lweSeshini). I-User Plane, eneneni, lijelo lokuhambisa i-traffic yabasebenzisi. Kwi-LTE yakudala, usasazo lwe-CP kunye ne-UP kulo lonke ujongano luhamba ngolu hlobo lulandelayo:
Iindlela ze-CP kunye ne-UP zokwandisa ze-NB-IoT ziphunyezwe kwi-MME, SGW kunye ne-PGW nodes, ezidityaniswe ngokwesiqhelo zibe yinto enye ebizwa ngokuba yi-C-SGN (iNode yeSango yokuSebenza ye-IoT). Umgangatho kwakhona uthatha ukuvela kwento entsha yenethiwekhi - SCEF (Service Capability Exposure Function). Ujongano phakathi kwe-MME kunye ne-SCEF kuthiwa yi-T6a kwaye iphunyezwa ngokusekwe kwiprotocol ye-DIAMETER. Nangona i-DIAMETER iyiprotocol yokubonisa, kwi-NB-IoT ilungiselelwe ukuhanjiswa kweemali ezincinci zedatha engeyiyo ye-IP.
Njengoko igama layo libonisa, i-SCEF yiNdawo yoMboniso yeNkonzo yokuXhobisa. Ngamanye amazwi, i-SCEF ifihla ukuntsokotha komsebenzi womnatha womsebenzi, kwaye ikwakhulula abaphuhlisi besicelo kwisidingo sokuchonga kunye nokuqinisekisa izixhobo eziphathwayo (UE), ukuvumela abancedisi besicelo (Umncedisi weSicelo, emva koku AS) ukufumana idatha kunye nokulawula izixhobo ngesixhobo esinye. Ujongano lwe-API.
Isichongi se-UE asiyiyo inombolo yomnxeba (MSISDN) okanye idilesi ye-IP, njengoko kwakunjalo kuthungelwano lwakudala lwe-2G/3G/LTE, kodwa into ebizwa ngokuba βyi-ID yangaphandleβ, echazwa ngumgangatho kwifomathi eqhelekileyo. kubaphuhlisi besicelo "@". Esi sisihloko esikhulu esahlukileyo esifanelwe yimathiriyeli eyahlukileyo, ngoko asiyi kuthetha ngayo ngokweenkcukacha ngoku.
Ngoku makhe sijonge olona tshintsho lubalulekileyo. "I-CIoT EPS Optimization" kukulungiswa kweendlela zokuhanjiswa kwezithuthi kunye nolawulo lweseshoni yababhalisi. Nazi ezona ziphambili:
- I-DoNAS
- I-NIDD
- I-PSM kunye ne-eDRX iindlela zokonga umbane
- I-HLCOM
I-DoNAS (Idatha ngaphezulu kweNAS):
Le yindlela eyilelwe ukwandisa ugqithiso lwedatha encinci.
Kwi-LTE yakudala, xa ubhalisa kuthungelwano, isixhobo somrhumi siseka uqhagamshelwano lwePDN (emva koku lubizwa ngokuba yiPDN) nge-eNodeB ukuya kwi-MME-SGW-PGW. Uqhagamshelwano lwe-UE-eNodeB-MME yinto ebizwa ngokuba yi-βSigning Radio Bearerβ (SRB). Ukuba kuyimfuneko ukuthumela/ukufumana idatha, i-UE iseka olunye uqhagamshelwano ne-eNodeB - βData Radio Bearerβ (DRB), ukuhambisa i-traffic yomsebenzisi kwi-SGW nangaphezulu kwi-PGW (i-interfaces S1-U ne-S5, ngokulandelelanayo) . Ekupheleni kotshintshiselwano kwaye ukuba akukho traffic ixesha elithile (ngokuqhelekileyo imizuzwana emi-5-20), olu xhulumaniso luphelisiwe kwaye isixhobo singena kwimodi yokulinda okanye "Imo Yokungasebenzi". Ukuba kuyimfuneko ukutshintshisa inxalenye entsha yedatha, i-SRB kunye ne-DRB zisetwa kwakhona.
Kwi-NB-IoT, ukuhanjiswa kwetrafikhi yomsebenzisi kunokuqhutywa ngesiteshi sokubonisa (SRB), kwimiyalezo ye-NAS protocol (). Ukumisela i-DRB akusafuneki. Oku kunciphisa kakhulu umthwalo wesignali, igcina izixhobo zomsakazo wenethiwekhi kwaye, okona kubaluleke kakhulu, ukwandisa ubomi bebhetri yesixhobo.
Kwicandelo le-eNodeB - i-MME, idatha yomsebenzisi iqala ukuhanjiswa kwi-interface ye-S1-MME, eyayingekho kwi-teknoloji ye-LTE ye-classical, kwaye i-protocol ye-NAS isetyenziselwa oku, apho "isikhongozeli sedatha yomsebenzisi" sibonakala.
Ukuqhuba ukuhanjiswa kwe "User Plane" ukusuka kwi-MME ukuya kwi-SGW, i-interface entsha ye-S11-U ibonakala, eyenzelwe ukuhanjiswa kwedatha encinci yomsebenzisi. Iprotocol ye-S11-U isekwe kwi-GTP-U v1, esetyenziselwa ukuhanjiswa kwePlanethi yoMsebenzisi kwezinye iindawo zonxibelelwano lwe-3GPP ye-architecture.
I-NIDD (ukuhanjiswa kwedatha engeyo-IP):
Njengenxalenye yokuphucula ngakumbi iindlela zokuhambisa amanani amancinci edatha, ukongeza kwiintlobo zePDN esele zikhona, ezifana ne-IPv4, IPv6 kunye ne-IPv4v6, olunye uhlobo luye lwavela - non-IP. Kule meko, i-UE ayinikwanga idilesi ye-IP kwaye idatha ihanjiswa ngaphandle kokusebenzisa i-IP protocol. Kukho izizathu ezininzi zoku:
- Izixhobo ze-IoT ezinjengezinzwa zinokuhambisa amanani amancinci kakhulu edatha, i-20 bytes okanye ngaphantsi. Ngenxa yokuba ubungakanani obuncinci bentloko ye-IP bungama-20 bytes, i-IP encapsulation ngamanye amaxesha inokubiza kakhulu;
- Akukho mfuneko yokuphumeza i-IP stack kwi-chip, ekhokelela ekunciphiseni kwabo iindleko (umbuzo wengxoxo kwizimvo).
Ngokubanzi, idilesi ye-IP iyimfuneko kwizixhobo ze-IoT ukuhambisa idatha kwi-Intanethi. Kwingcamango ye-NB-IoT, i-SCEF isebenza njengendawo yokudibanisa ye-AS enye, kunye nokutshintshiselana kwedatha phakathi kwezixhobo kunye neeseva zesicelo kwenzeka nge-API. Ukungabikho kwe-SCEF, idatha engeyiyo ye-IP inokudluliselwa kwi-AS nge-tunnel ye-Point-to-Point (PtP) ukusuka kwi-PGW kunye ne-IP encapsulation iya kwenziwa kuyo.
Konke oku kuhambelana ne-NB-IoT paradigm - ukwenza lula kunye nokunciphisa iindleko zezixhobo.
I-PSM kunye ne-eDRX iindlela zokugcina amandla:
Enye yeenzuzo eziphambili zothungelwano lwe-LPWAN kukusebenza kakuhle kwamandla. Isixhobo kuthiwa sihlala ukuya kuthi ga kwiminyaka eli-10 yobomi bebhetri kwibhetri enye. Makhe sibone indlela amaxabiso anjalo aphunyezwa ngayo.
Xa isixhobo sisebenzisa awona mandla mancinci? Ilungile xa icinyiwe. Kwaye ukuba akunakwenzeka ukuphelisa ngokupheleleyo amandla isixhobo, masiyikhuphe amandla kwimodyuli yerediyo ixesha elide ingafuneki. Ufuna nje ukulungelelanisa oku kunye nomsebenzi womnatha kuqala.
PSM (imowudi yokugcina amandla):
Imodi yokugcina amandla e-PSM ivumela isixhobo ukuba sivale imodyuli yerediyo ixesha elide, ngelixa lihlala libhalisiwe kwinethiwekhi, kwaye lingaphindi lifake i-PDN rhoqo xa lifuna ukudlulisa idatha.
Ukwazisa uthungelwano ukuba isixhobo sisafumaneka, siqalisa rhoqo inkqubo yohlaziyo - Uhlaziyo lweNdawo yokuTracking (TAU). I-frequency yale nkqubo imiselwe yi-network usebenzisa i-timer T3412, ixabiso lalo elidluliselwa kwisixhobo ngexesha lenkqubo yokuQeqesha okanye i-TAU elandelayo. Kwi-LTE yakudala, ixabiso elingagqibekanga lale timer yimizuzu engama-54, kwaye ubuninzi yimizuzu eyi-186. Nangona kunjalo, ukuqinisekisa ukusebenza kakuhle kwamandla, imfuno yokuhamba emoyeni rhoqo ngemizuzu ye-186 ibiza kakhulu. Indlela yePSM yaphuhliswa ukusombulula le ngxaki.
Isixhobo sivula imowudi ye-PSM ngokudlulisa amaxabiso ezibali-xesha ezimbini T3324 kunye ne-T3412-Eyandisiweyo kwimiyalezo ethi "Namathisela isicelo" okanye "iSicelo soMkhondo". Eyokuqala imisela ixesha apho isixhobo siya kufumaneka emva kokutshintshela kwi "Idle Mode". Okwesibini lixesha emva kokuba i-TAU kufuneka yenziwe, kuphela ngoku ixabiso layo linokufikelela kwimizuzwana ye-35712000 okanye iintsuku ezingama-413. Kuxhomekeka kuseto, i-MME inokwamkela amaxabiso esibali-xesha afunyenwe kwisixhobo okanye uwatshintshe ngokuthumela amaxabiso amatsha kwimiyalezo ethi "Namathisela uYamkela" okanye "Yokulandela uHlaziyo lweNdawo yokulanda". Ngoku isixhobo asikwazi ukuvula imodyuli yerediyo kangangeentsuku ezingama-413 kwaye uhlale ubhalisiwe kwinethiwekhi. Ngenxa yoko, sifumana ukonga okukhulu kwimithombo yenethiwekhi kunye nokusebenza kakuhle kwamandla kwezixhobo!
Nangona kunjalo, kule mowudi isixhobo asifumaneki kunxibelelwano olungenayo kuphela. Ukuba kuyimfuneko ukudlulisa into kwiseva yesicelo, ifowuni inokuphuma kwi-PSM nangaliphi na ixesha kwaye ithumele idatha, emva koko ihlala isebenza ngexesha le-T3324 timer ukufumana imiyalezo yolwazi evela kwi-AS (ukuba ikhona).
eDRX (ulwamkelo olwandisiweyo olungaqhubekiyo):
I-eDRX, Ulwamkelo lweThutyana oloNgeziweyo. Ukudlulisa idatha kwisixhobo esikwi "Idle mode", inethwekhi yenza inkqubo yokwazisa - "Paging". Ekufumaneni i-paging, isixhobo siqalisa ukusekwa kwe-SRB kunxibelelwano oluthe kratya nenethiwekhi. Kodwa ukuze ungaphoswa ngumyalezo wePaging obhekiswa kuyo, isixhobo kufuneka sihlale sibeke iliso emoyeni werediyo, ekwatya kakhulu amandla.
I-eDRX yindlela apho isixhobo singafumani miyalezo rhoqo kwinethiwekhi, kodwa ngamaxesha athile. Ngexesha le-Attach okanye iinkqubo ze-TAU, isixhobo siyavumelana nenethiwekhi ngexesha lekhefu apho siya "kumamela" kusasazo. Ngokufanelekileyo, inkqubo yokuPaging iya kwenziwa ngexesha elinye. Kwimo ye-eDRX, ukusebenza kwesixhobo kwahlulwe ngokwemijikelo (umjikelo we-eDRX). Ekuqaleni komjikelo ngamnye kukho into ebizwa ngokuba yi "paging window" (Ifestile yePaging Time, emva koko i-PTW) - eli lixesha apho isixhobo simamela ijelo lomsakazo. Ekupheleni kwe-PTW, isixhobo sicima imodyuli yerediyo kude kube sekupheleni komjikelo.
I-HLCOM (unxibelelwano olukwixesha elide):
Ukuba ifuna ukudlulisa idatha kwi-Uplink, isixhobo sinokuphuma nokuba yeyiphi kwezi ndlela zimbini zogcino lwamandla ngaphandle kokulinda i-PSM okanye umjikelo we-eDRX ukugqiba. Kodwa kunokwenzeka ukudlulisa idatha kwisixhobo kuphela xa sisebenza.
Ukusebenza kwe-HLCOM okanye unxibelelwano oluphezulu lwe-latency yi-buffering yeepakethi ze-Downlink kwi-SGW ngelixa ifowuni ikwimo yokugcinwa kwamandla kwaye ingafumaneki kunxibelelwano. Iipakethi ezithintelweyo ziya kuhanjiswa ngokukhawuleza xa isixhobo siphuma kwi-PSM ngokwenza i-TAU okanye ukudlula i-Uplink traffic, okanye xa i-PTW isenzeka.
Oku, ngokuqinisekileyo, kufuna ulwazi kwicala labaphuhlisi beemveliso ze-IoT, ekubeni unxibelelwano kunye nesixhobo alufezekiswanga ngexesha langempela kwaye lufuna indlela ethile yokuyila ingqiqo yezoshishino zezicelo.
Ukuqukumbela, masithi: ukungeniswa kwento entsha kuhlala kumnandi, kodwa ngoku sijongana nomgangatho ongakhange uvavanywe ngokupheleleyo nakwi "bisons" zehlabathi, njengeVodafone kunye neTelefonica - ngoko ke kumnandi ngokuphindwe kabini. Unikezelo lwethu lwemathiriyeli aluzenzi lugqibelele ngokupheleleyo, kodwa sinethemba lokuba lunika ukuqonda okwaneleyo kobuchwephesha. Siya kuyivuyela impendulo yakho.
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