{"id":52138,"date":"2019-11-01T00:00:00","date_gmt":"2019-10-31T21:00:00","guid":{"rendered":"https:\/\/prohoster.info\/blog\/blog_prohoster\/nb-iot-kak-on-rabotaet-chast-3-scef-edinoe-okno-dostupa-k-uslugam-operatora"},"modified":"2020-02-18T13:59:48","modified_gmt":"2020-02-18T10:59:48","slug":"nb-iot-kak-on-rabotaet-chast-3-scef-edinoe-okno-dostupa-k-uslugam-operatora","status":"publish","type":"post","link":"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nb-iot-kak-on-rabotaet-chast-3-scef-edinoe-okno-dostupa-k-uslugam-operatora","title":{"rendered":"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"<p><b>V \u010dl\u00e1nku \u201e<noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/ru_mts\/blog\/431648\/\">NB-IoT: jak to funguje? \u010c\u00e1st 2<\/a><\/noindex>\u201c jsme zm\u00ednili architekturu paketov\u00e9ho j\u00e1dra s\u00edt\u011b NB-IoT a vznik nov\u00e9ho uzlu SCEF. V t\u0159et\u00ed \u010d\u00e1sti vysv\u011btlujeme, co to je a k \u010demu je to dobr\u00e9?<\/b><\/p>\n<p><img decoding=\"async\" alt=\"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora\" src=\"\/wp-content\/uploads\/2019\/11\/95652a1e2bfce0589b51b106ebf6e64f.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nP\u0159i vytv\u00e1\u0159en\u00ed M2M slu\u017eby se v\u00fdvoj\u00e1\u0159i aplikac\u00ed pot\u00fdkaj\u00ed s n\u00e1sleduj\u00edc\u00edmi ot\u00e1zkami:<\/p>\n<ul>\n<li>jak identifikovat za\u0159\u00edzen\u00ed;<\/li>\n<li>jak\u00fd pou\u017e\u00edt algoritmus pro ov\u011b\u0159en\u00ed a potvrzen\u00ed pravosti;<\/li>\n<li>jak\u00fd vybrat transportn\u00ed protokol pro komunikaci s za\u0159\u00edzen\u00edmi;<\/li>\n<li>jak garantovat doru\u010den\u00ed dat na za\u0159\u00edzen\u00ed;<\/li>\n<li>jak organizovat a stanovit pravidla pro v\u00fdm\u011bnu dat s nimi;<\/li>\n<li>jak kontrolovat a v re\u00e1ln\u00e9m \u010dase z\u00edskat informace o jejich stavu;<\/li>\n<li>jak sou\u010dasn\u011b doru\u010dit data skupin\u011b sv\u00fdch za\u0159\u00edzen\u00ed;<\/li>\n<li>jak sou\u010dasn\u011b poslat data z jednoho za\u0159\u00edzen\u00ed na v\u00edce klient\u016f;<\/li>\n<li>jak z\u00edskat jednotn\u00fd p\u0159\u00edstup k dal\u0161\u00edm slu\u017eb\u00e1m oper\u00e1tora pro spr\u00e1vu sv\u00e9ho za\u0159\u00edzen\u00ed. <\/li>\n<\/ul>\n<p>\nPro jejich \u0159e\u0161en\u00ed je \u010dasto t\u0159eba vytv\u00e1\u0159et propriet\u00e1rn\u00ed technicky \u201et\u011b\u017ek\u00e1\u201c \u0159e\u0161en\u00ed, co\u017e zvy\u0161uje n\u00e1klady na pr\u00e1ci a \u010das pot\u0159ebn\u00fd k uveden\u00ed slu\u017eeb na trh. A pr\u00e1v\u011b zde p\u0159ich\u00e1z\u00ed nov\u00fd uzel SCEF na pomoc.<noindex><a rel=\"nofollow\" name=\"habracut\"><\/a><\/noindex><\/p>\n<p>Podle definice 3GPP je SCEF (funkce exponov\u00e1n\u00ed schopnost\u00ed slu\u017eeb) zcela novou sou\u010d\u00e1st\u00ed architektury 3GPP, jej\u00ed\u017e funkc\u00ed je bezpe\u010dn\u00e9 exponov\u00e1n\u00ed slu\u017eeb a schopnost\u00ed, kter\u00e9 poskytuj\u00ed s\u00ed\u0165ov\u00e9 rozhran\u00ed 3GPP prost\u0159ednictv\u00edm API. <\/p>\n<p>Jednodu\u0161e \u0159e\u010deno, SCEF je zprost\u0159edkovatel mezi s\u00edt\u00ed a aplika\u010dn\u00edm serverem (application server \u2014 AS), jedin\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora pro spr\u00e1vu sv\u00e9ho M2M za\u0159\u00edzen\u00ed v s\u00edti NB-IoT prost\u0159ednictv\u00edm intuitivn\u00edho standardizovan\u00e9ho API rozhran\u00ed.<\/p>\n<p>SCEF skryje slo\u017eitost s\u00edt\u011b oper\u00e1tora, co\u017e umo\u017e\u0148uje v\u00fdvoj\u00e1\u0159\u016fm aplikac\u00ed abstrahovat od slo\u017eit\u00fdch, specifick\u00fdch mechanism\u016f interakce s za\u0159\u00edzen\u00edmi.<\/p>\n<p>D\u00edky p\u0159evodu s\u00ed\u0165ov\u00fdch protokol\u016f na v\u00fdvoj\u00e1\u0159\u016fm zn\u00e1m\u00e9 API rozhran\u00ed SCEF usnad\u0148uje vytv\u00e1\u0159en\u00ed nov\u00fdch slu\u017eeb a zkracuje \u010das pot\u0159ebn\u00fd k uveden\u00ed na trh. Nov\u00fd uzel tak\u00e9 zahrnuje funkce identifikace\/autentizace mobiln\u00edch za\u0159\u00edzen\u00ed a stanovov\u00e1n\u00ed pravidel pro v\u00fdm\u011bnu dat mezi za\u0159\u00edzen\u00edm a AS, \u010d\u00edm\u017e uvol\u0148uje v\u00fdvoj\u00e1\u0159e aplikac\u00ed od nutnosti implementovat tyto funkce na sv\u00e9 stran\u011b a p\u0159en\u00e1\u0161\u00ed tyto \u00fakoly na ramena oper\u00e1tora.<\/p>\n<p>SCEF zaji\u0161\u0165uje rozhran\u00ed pot\u0159ebn\u00e1 pro autentizaci a autorizaci aplika\u010dn\u00edch server\u016f, udr\u017eov\u00e1n\u00ed mobility UE, p\u0159enos dat a spou\u0161t\u011bn\u00ed za\u0159\u00edzen\u00ed, p\u0159\u00edstup k dal\u0161\u00edm slu\u017eb\u00e1m a funkc\u00edm s\u00edt\u011b oper\u00e1tora.<\/p>\n<p>Sm\u011brem k AS existuje pouze jedin\u00e9 rozhran\u00ed T8, API rozhran\u00ed (HTTP\/JSON), standardizovan\u00e9 3GPP. V\u0161echna rozhran\u00ed, krom\u011b T8, funguj\u00ed na b\u00e1zi protokolu DIAMETER (obr\u00e1zek 1).<\/p>\n<p><img decoding=\"async\" alt=\"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora\" src=\"\/wp-content\/uploads\/2019\/11\/6538d7d9e0d94244e6415b78f080b159.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nT6a je rozhran\u00ed mezi SCEF a MME. Pou\u017e\u00edv\u00e1 se pro procedury \u0159\u00edzen\u00ed mobility a relac\u00ed, p\u0159enos non-IP dat, provizioning monitorovac\u00edch ud\u00e1lost\u00ed a p\u0159\u00edjem zpr\u00e1v o nich.<\/p>\n<p>S6t je rozhran\u00ed mezi SCEF a HSS. Je nutn\u00e9 pro autentizaci p\u0159edplatitele, autorizaci aplika\u010dn\u00edch server\u016f, z\u00edsk\u00e1n\u00ed p\u00e1ru external ID a IMSI\/MSISDN, provizioning monitorovac\u00edch ud\u00e1lost\u00ed a p\u0159\u00edjem zpr\u00e1v o nich.<\/p>\n<p>S6m\/T4 jsou rozhran\u00ed od SCEF k HSS a SMS-C (ve 3GPP je definov\u00e1n uzel MTC-IWF, kter\u00fd se pou\u017e\u00edv\u00e1 pro spou\u0161t\u011bn\u00ed za\u0159\u00edzen\u00ed a p\u0159enos SMS v s\u00edt\u00edch NB-IoT. Nicm\u00e9n\u011b ve v\u0161ech realizac\u00edch je funk\u010dnost tohoto uzlu integrov\u00e1na do SCEF, tak\u017ee pro zjednodu\u0161en\u00ed sch\u00e9matu ho nebudeme zva\u017eovat odd\u011blen\u011b). Pou\u017e\u00edvaj\u00ed se pro z\u00edsk\u00e1n\u00ed sm\u011brov\u00fdch informac\u00ed pro odes\u00edl\u00e1n\u00ed SMS a interakci se SMS centrem.<\/p>\n<p>T8 je API rozhran\u00ed pro interakci SCEF s aplika\u010dn\u00edmi servery. Skrze toto rozhran\u00ed se p\u0159en\u00e1\u0161ej\u00ed jak \u0159\u00eddic\u00ed p\u0159\u00edkazy, tak i provoz.<\/p>\n<p>*ve skute\u010dnosti existuje v\u00edce rozhran\u00ed, zde jsou uvedena pouze ta nejz\u00e1kladn\u011bj\u0161\u00ed. Kompletn\u00ed seznam je uveden ve 3GPP 23.682 (4.3.2 Seznam referen\u010dn\u00edch bod\u016f).<\/p>\n<p>N\u00ed\u017ee jsou uvedeny kl\u00ed\u010dov\u00e9 funkce a slu\u017eby SCEF:<\/p>\n<ul>\n<li>p\u0159i\u0159azen\u00ed identifik\u00e1toru SIM karty (IMSI) k external ID; <\/li>\n<li>p\u0159enos non-IP provozu (Non-IP Data Delivery, NIDD);<\/li>\n<li>skupinov\u00e9 operace s pou\u017eit\u00edm external group ID;<\/li>\n<li>podpora re\u017eimu p\u0159enosu dat s potvrzen\u00edm;<\/li>\n<li>bufferov\u00e1n\u00ed dat MO (Mobile Originated) a MT (Mobile Terminated);<\/li>\n<li>autentizace a autorizace za\u0159\u00edzen\u00ed a aplika\u010dn\u00edch server\u016f;<\/li>\n<li>sou\u010dasn\u00e9 pou\u017e\u00edv\u00e1n\u00ed dat jednoho UE n\u011bkolika AS;<\/li>\n<li>podpora speci\u00e1ln\u00edch funkc\u00ed sledov\u00e1n\u00ed stavu UE (MONTE \u2013 Monitoring Events);<\/li>\n<li>spou\u0161t\u011bn\u00ed za\u0159\u00edzen\u00ed;<\/li>\n<li>zaji\u0161t\u011bn\u00ed roamingu non-IP dat.<\/li>\n<\/ul>\n<p>\nHlavn\u00ed princip interakce mezi AS a SCEF je zalo\u017een na syst\u00e9mu tzv. p\u0159edplatn\u00e9ho. P\u0159i pot\u0159eb\u011b z\u00edsk\u00e1n\u00ed p\u0159\u00edstupu k ur\u010dit\u00e9mu servisu SCEF pro konkr\u00e9tn\u00ed UE, je serveru aplikac\u00ed nutn\u00e9 vytvo\u0159it p\u0159edplatn\u00e9 zasl\u00e1n\u00edm p\u0159\u00edkazu na konkr\u00e9tn\u00ed API po\u017eadovan\u00e9ho servisu a v odpov\u011bdi obdr\u017eet jedine\u010dn\u00fd identifik\u00e1tor. Pot\u00e9 ve\u0161ker\u00e9 dal\u0161\u00ed akce a komunikace s UE v r\u00e1mci tohoto servisu prob\u011bhnou s pou\u017eit\u00edm tohoto identifik\u00e1toru.<\/p>\n<p><b>Extern\u00ed ID: univerz\u00e1ln\u00ed identifik\u00e1tor za\u0159\u00edzen\u00ed<\/b><\/p>\n<p>Jedn\u00edm z nejd\u016fle\u017eit\u011bj\u0161\u00edch zm\u011bn v syst\u00e9mu interakce AS s za\u0159\u00edzen\u00edmi p\u0159i pr\u00e1ci p\u0159es SCEF je vznik univerz\u00e1ln\u00edho identifik\u00e1toru. Nyn\u00ed m\u00edsto telefonn\u00edho \u010d\u00edsla (MSISDN) nebo IP adresy, jak tomu bylo v klasick\u00e9 s\u00edti 2G\/3G\/LTE, se identifik\u00e1torem za\u0159\u00edzen\u00ed pro server aplikac\u00ed st\u00e1v\u00e1 \u201eextern\u00ed ID\u201c. Ten je definov\u00e1n standardem v obvykl\u00e9m form\u00e1tu pro v\u00fdvoj\u00e1\u0159e aplikac\u00ed \u201e@\u201c.<\/p>\n<p>V\u00fdvoj\u00e1\u0159i ji\u017e nemus\u00ed implementovat algoritmy pro autentizaci za\u0159\u00edzen\u00ed, s\u00ed\u0165 tuto funkci pln\u011b p\u0159eb\u00edr\u00e1. Extern\u00ed ID je spojeno s IMSI a v\u00fdvoj\u00e1\u0159 si m\u016f\u017ee b\u00fdt jist\u00fd, \u017ee p\u0159i komunikaci s konkr\u00e9tn\u00edm extern\u00edm ID interaguje s konkr\u00e9tn\u00ed SIM kartou. P\u0159i pou\u017eit\u00ed SIM \u010dipu vznik\u00e1 dokonce unik\u00e1tn\u00ed situace, kdy extern\u00ed ID jednozna\u010dn\u011b identifikuje konkr\u00e9tn\u00ed za\u0159\u00edzen\u00ed!<\/p>\n<p>Nav\u00edc lze k jednomu IMSI p\u0159i\u0159adit v\u00edce extern\u00edch ID \u2014 to vytv\u00e1\u0159\u00ed je\u0161t\u011b zaj\u00edmav\u011bj\u0161\u00ed situaci, kdy extern\u00ed ID jednozna\u010dn\u011b identifikuje konkr\u00e9tn\u00ed aplikaci odpov\u00eddaj\u00edc\u00ed za ur\u010ditou slu\u017ebu na konkr\u00e9tn\u00edm za\u0159\u00edzen\u00ed.<\/p>\n<p>Tak\u00e9 vznik\u00e1 skupinov\u00fd identifik\u00e1tor \u2014 extern\u00ed skupinov\u00e9 ID, kter\u00e9 zahrnuje sadu jednotliv\u00fdch extern\u00edch ID. Nyn\u00ed jedn\u00edm po\u017eadavkem na SCEF m\u016f\u017ee AS iniciovat skupinov\u00e9 operace \u2014 zasl\u00e1n\u00ed dat nebo p\u0159\u00edkaz\u016f pro \u0159adu za\u0159\u00edzen\u00ed spojen\u00fdch do jedin\u00e9 logick\u00e9 skupiny.<\/p>\n<p>Z d\u016fvodu toho, \u017ee pro v\u00fdvoj\u00e1\u0159e AS p\u0159echod na nov\u00fd identifik\u00e1tor za\u0159\u00edzen\u00ed nem\u016f\u017ee b\u00fdt okam\u017eit\u00fd, SCEF ponechal mo\u017enost komunikace AS s UE prost\u0159ednictv\u00edm standardn\u00edho \u010d\u00edsla \u2013 MSISDN.<\/p>\n<p><b>P\u0159enos non-IP provozu (Non-IP Data Delivery, NIDD)<\/b><\/p>\n<p>Ve NB-IoT, v r\u00e1mci optimalizace mechanism\u016f p\u0159enosu mal\u00fdch objem\u016f dat, se vedle ji\u017e existuj\u00edc\u00edch typ\u016f PDN, jako jsou IPv4, IPv6 a IPv4v6, objevil je\u0161t\u011b jeden typ \u2014 non-IP. V tomto p\u0159\u00edpad\u011b nen\u00ed za\u0159\u00edzen\u00ed (UE) p\u0159i\u0159azen \u017e\u00e1dn\u00fd IP adresa a data jsou p\u0159en\u00e1\u0161ena bez pou\u017eit\u00ed protokolu IP. Pro tyto p\u0159ipojen\u00ed m\u016f\u017ee b\u00fdt provoz sm\u011brov\u00e1n dv\u011bma zp\u016fsoby: klasick\u00fdm \u2014 MME -&gt; SGW -&gt; PGW a d\u00e1le p\u0159es PtP tunel do AS (obr. 2) nebo pomoc\u00ed SCEF (obr. 3). <\/p>\n<p><img decoding=\"async\" alt=\"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora\" src=\"\/wp-content\/uploads\/2019\/11\/557caf393c9da84fc635c57bb5ecf4a5.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nKlasick\u00fd zp\u016fsob nenab\u00edz\u00ed \u017e\u00e1dn\u00e9 zvl\u00e1\u0161tn\u00ed v\u00fdhody oproti IP provozu, krom\u011b zmen\u0161en\u00ed velikosti p\u0159en\u00e1\u0161en\u00fdch paket\u016f d\u00edky absenci IP hlavi\u010dek. Pou\u017eit\u00ed SCEF v\u0161ak otev\u00edr\u00e1 celou \u0159adu nov\u00fdch mo\u017enost\u00ed a v\u00fdrazn\u011b zjednodu\u0161uje postupy interakce se za\u0159\u00edzen\u00edmi.<\/p>\n<p>P\u0159i p\u0159enosu dat p\u0159es SCEF se objevuj\u00ed dv\u011b velmi d\u016fle\u017eit\u00e9 v\u00fdhody oproti klasick\u00e9mu IP provozu: <\/p>\n<p><u>Dod\u00e1n\u00ed MT provozu k za\u0159\u00edzen\u00ed podle extern\u00edho ID.<\/u><\/p>\n<p>Aby bylo mo\u017en\u00e9 poslat zpr\u00e1vu na klasick\u00e9 IP za\u0159\u00edzen\u00ed, mus\u00ed AS zn\u00e1t jeho IP adresu. Tady nast\u00e1v\u00e1 probl\u00e9m: proto\u017ee za\u0159\u00edzen\u00ed obvykle p\u0159i registraci z\u00edsk\u00e1v\u00e1 \"\u0161edou\" IP adresu, komunikuje se serverem aplikac\u00ed, kter\u00fd se nach\u00e1z\u00ed v internetu, p\u0159es uzel NAT, kde prob\u00edh\u00e1 p\u0159eklad \u0161ed\u00e9 adresy na b\u00edlou. Svazek \u0161ed\u00e9 a b\u00edl\u00e9 IP adresy dr\u017e\u00ed omezen\u00fd \u010das, v z\u00e1vislosti na nastaven\u00ed NAT. Pr\u016fm\u011brn\u011b pro TCP nebo UDP \u2014 ne v\u00edce ne\u017e p\u011bt minut. To znamen\u00e1, \u017ee pokud v pr\u016fb\u011bhu 5 minut nedoch\u00e1z\u00ed k v\u00fdm\u011bn\u011b dat s t\u00edmto za\u0159\u00edzen\u00edm, svazek se rozpadne a za\u0159\u00edzen\u00ed p\u0159estane b\u00fdt dostupn\u00e9 na t\u00e9 b\u00edl\u00e9 adrese, se kterou byla zah\u00e1jena relace s AS. Existuje n\u011bkolik \u0159e\u0161en\u00ed: <\/p>\n<p>1. Pou\u017e\u00edvat heartbeat. Jakmile je spojen\u00ed nav\u00e1z\u00e1no, za\u0159\u00edzen\u00ed by m\u011blo vym\u011b\u0148ovat s AS pakety ka\u017ed\u00fdch n\u011bkolik minut, \u010d\u00edm\u017e by zabr\u00e1nilo uzav\u0159en\u00ed p\u0159eklad\u016f v NAT. Ale zde nem\u016f\u017ee b\u00fdt \u0159e\u010d o \u017e\u00e1dn\u00e9 energetick\u00e9 efektivnosti. <\/p>\n<p>2. Poka\u017ed\u00e9, kdy\u017e je pot\u0159eba zkontrolovat existenci paket\u016f pro za\u0159\u00edzen\u00ed na AS \u2014 pos\u00edlat zpr\u00e1vu v uplink.<\/p>\n<p>3. Vytvo\u0159it soukrom\u00fd APN (VRF), kde server aplikac\u00ed a za\u0159\u00edzen\u00ed budou v jedn\u00e9 pods\u00edti, a p\u0159id\u011blit za\u0159\u00edzen\u00edm statick\u00e9 IP adresy. Bude to fungovat, ale je to t\u00e9m\u011b\u0159 nerealizovateln\u00e9, kdy\u017e jde o park tis\u00edc\u016f, des\u00edtek tis\u00edc\u016f za\u0159\u00edzen\u00ed.<\/p>\n<p>4. Nakonec je nejvhodn\u011bj\u0161\u00ed mo\u017enost: pou\u017e\u00edt IPv6, pro n\u011bj nen\u00ed pot\u0159eba NAT, proto\u017ee IPv6 adresy jsou p\u0159\u00edmo dostupn\u00e9 z internetu. Av\u0161ak i v tomto p\u0159\u00edpad\u011b, p\u0159i op\u011btovn\u00e9 registraci za\u0159\u00edzen\u00ed, dostane nov\u00e9 IPv6 adresy a nebude ji\u017e dostupn\u00e9 podle p\u0159edchoz\u00edho. <\/p>\n<p>Je tedy nutn\u00e9 odeslat n\u011bjak\u00fd inicia\u010dn\u00ed paket s identifik\u00e1torem za\u0159\u00edzen\u00ed na server, aby se ozn\u00e1mila nov\u00e1 IP adresa za\u0159\u00edzen\u00ed. Pot\u00e9 \u010dekat na potvrzuj\u00edc\u00ed paket od AS, co\u017e tak\u00e9 ovliv\u0148uje energetickou \u00fa\u010dinnost.<\/p>\n<p>Tyto metody dob\u0159e funguj\u00ed pro 2G\/3G\/LTE za\u0159\u00edzen\u00ed, kde nejsou kladeny p\u0159\u00edsn\u00e9 po\u017eadavky na autonomie a, n\u00e1sledn\u011b, nejsou \u017e\u00e1dn\u00e1 omezen\u00ed na \u010das v \u00e9teru a na trafik. Pro NB-IoT tyto metody nejsou vhodn\u00e9 z d\u016fvodu vysok\u00e9 energetick\u00e9 n\u00e1ro\u010dnosti.<\/p>\n<p>SCEF tento probl\u00e9m \u0159e\u0161\u00ed: jeliko\u017e jedin\u00fdm identifik\u00e1torem za\u0159\u00edzen\u00ed pro AS je external ID, sta\u010d\u00ed, aby AS poslal datov\u00fd paket na SCEF pro konkr\u00e9tn\u00ed external ID, o v\u0161e ostatn\u00ed se postar\u00e1 SCEF. Pokud je za\u0159\u00edzen\u00ed v re\u017eimu \u00faspory energie PSM nebo eDRX, budou data bufferov\u00e1na a doru\u010dena, jakmile se za\u0159\u00edzen\u00ed stane dostupn\u00fdm. Pokud je v\u0161ak za\u0159\u00edzen\u00ed dostupn\u00e9 pro trafik, data budou doru\u010dena okam\u017eit\u011b. Toto plat\u00ed i pro \u0159\u00eddic\u00ed p\u0159\u00edkazy.<\/p>\n<p>V ka\u017ed\u00e9m okam\u017eiku m\u016f\u017ee AS odvolat bufferovanou zpr\u00e1vu sm\u011brem k UE nebo ji nahradit novou.<\/p>\n<p>Mechanismus bufferov\u00e1n\u00ed m\u016f\u017ee b\u00fdt tak\u00e9 aplikov\u00e1n p\u0159i p\u0159enosu MO-dat od UE sm\u011brem k AS. Pokud SCEF nemohl doru\u010dit data k AS okam\u017eit\u011b, nap\u0159\u00edklad pokud prob\u00edhaj\u00ed servisn\u00ed pr\u00e1ce na serverech AS, tyto pakety budou bufferov\u00e1ny a zaru\u010den\u011b doru\u010deny, jakmile bude AS dostupn\u00fd.<\/p>\n<p>Jak bylo zm\u00edn\u011bno v\u00fd\u0161e, p\u0159\u00edstup k ur\u010dit\u00e9mu servisu a UE pro AS (a NIDD \u2013 to je servis) je regulov\u00e1n pravidly a politikami na stran\u011b SCEF, co\u017e umo\u017e\u0148uje realizaci jedine\u010dn\u00e9 mo\u017enosti sou\u010dasn\u00e9ho pou\u017eit\u00ed dat jednoho UE n\u011bkolika AS. Tedy, pokud se n\u011bkolik AS p\u0159ihl\u00e1silo k jednomu UE, pak po obdr\u017een\u00ed dat od UE SCEF tyto data rozes\u00edl\u00e1 na v\u0161echny p\u0159ihl\u00e1\u0161en\u00e9 AS. To je dob\u0159e vhodn\u00e9 pro p\u0159\u00edpady, kdy tv\u016frce parku specializovan\u00fdch za\u0159\u00edzen\u00ed sd\u00edl\u00ed data mezi n\u011bkolika klienty. Nap\u0159\u00edklad, vytvo\u0159en\u00edm s\u00edt\u011b meteorologick\u00fdch stanic funguj\u00edc\u00edch na NB-IoT lze prod\u00e1vat data z nich mnoha slu\u017eb\u00e1m sou\u010dasn\u011b.<\/p>\n<p><b>Mechanismus zaru\u010den\u00e9ho doru\u010den\u00ed zpr\u00e1v <\/b><\/p>\n<p>Reliable Data Service \u2014 mechanizmus zaru\u010den\u00e9ho doru\u010den\u00ed MO a MT zpr\u00e1v bez pou\u017eit\u00ed specializovan\u00fdch algoritm\u016f na protokolov\u00e9 \u00farovni, jako je nap\u0159\u00edklad handshake v TCP. Funguje na z\u00e1klad\u011b zahrnut\u00ed zvl\u00e1\u0161tn\u00edho p\u0159\u00edznaku do \u0159\u00eddic\u00ed \u010d\u00e1sti zpr\u00e1vy p\u0159i v\u00fdm\u011bn\u011b mezi UE a SCEF. Aktivaci nebo deaktivaci tohoto mechanizmu p\u0159i p\u0159enosu dat rozhoduje AS.<\/p>\n<p>Pokud je mechanizmus aktivov\u00e1n, UE p\u0159i pot\u0159eb\u011b zaru\u010den\u00e9ho doru\u010den\u00ed MO dat zahrnuje zvl\u00e1\u0161tn\u00ed p\u0159\u00edznak do \u0159\u00eddic\u00ed \u010d\u00e1sti paketu. P\u0159i obdr\u017een\u00ed takov\u00e9ho paketu SCEF odpov\u00edd\u00e1 UE potvrzen\u00edm. Pokud UE neobdr\u017eela paket s potvrzen\u00edm, paket sm\u011brem k SCEF bude znovu odesl\u00e1n. To sam\u00e9 plat\u00ed i pro MT data.<\/p>\n<p><b>Monitorov\u00e1n\u00ed za\u0159\u00edzen\u00ed (monitoring events- MONTE)<\/b><\/p>\n<p>Jak bylo uvedeno v\u00fd\u0161e, funkcionalita SCEF, mimo jin\u00e9, zahrnuje funkce kontroly stavu UE, tzv. monitorov\u00e1n\u00ed za\u0159\u00edzen\u00ed. A pokud jsou nov\u00e9 identifik\u00e1tory a mechanizmy p\u0159enosu dat optimalizace (i kdy\u017e velmi z\u00e1va\u017en\u00e9) ji\u017e existuj\u00edc\u00edch postup\u016f, MONTE je zcela nov\u00e1 funkcionalita, kter\u00e1 nen\u00ed dostupn\u00e1 v s\u00edt\u00edch 2G\/3G\/LTE. MONTE umo\u017e\u0148uje AS sledovat takov\u00e9 parametry za\u0159\u00edzen\u00ed, jako je stav p\u0159ipojen\u00ed, dostupnost pro komunikaci, poloha, roamingov\u00fd status atd. O ka\u017ed\u00e9m z nich se dozv\u00edte podrobn\u011bji pozd\u011bji.<\/p>\n<p>Pokud je t\u0159eba aktivovat jakoukoli ud\u00e1lost monitorov\u00e1n\u00ed pro za\u0159\u00edzen\u00ed nebo skupinu za\u0159\u00edzen\u00ed, AS se p\u0159ihl\u00e1s\u00ed k odpov\u00eddaj\u00edc\u00ed slu\u017eb\u011b zasl\u00e1n\u00edm p\u0159\u00edkazu p\u0159\u00edslu\u0161n\u00e9ho API MONTE na SCEF, kter\u00fd zahrnuje takov\u00e9 parametry, jako je external Id nebo external group ID, identifik\u00e1tor AS, typ monitorov\u00e1n\u00ed, po\u010det report\u016f, kter\u00e9 AS chce obdr\u017eet. Pokud je AS autorizov\u00e1n k proveden\u00ed dotazu, SCEF podle typu provizuje ud\u00e1lost na HSS nebo MME. P\u0159i vzniku ud\u00e1losti MME nebo HSS generuj\u00ed report sm\u011brem k SCEF, kter\u00fd ho pak ode\u0161le na AS.<\/p>\n<p>Provizionov\u00e1n\u00ed v\u0161ech ud\u00e1lost\u00ed, krom\u011b \u201ePo\u010det UEs p\u0159\u00edtomn\u00fdch v geografick\u00e9 oblasti\u201c, prob\u00edh\u00e1 prost\u0159ednictv\u00edm HSS. Dv\u011b ud\u00e1losti \u201eChange of IMSI-IMEI Association\u201c a \u201eRoaming Status\u201c \u2014 se sleduj\u00ed p\u0159\u00edmo na HSS, ostatn\u00ed HSS provizuje na MME.<br \/>\nUd\u00e1losti mohou b\u00fdt jak jednor\u00e1zov\u00e9, tak periodick\u00e9, a jsou ur\u010deny jejich typem.<\/p>\n<p><img decoding=\"async\" alt=\"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora\" src=\"\/wp-content\/uploads\/2019\/11\/da265ed0443b7459d28101aa07adf221.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\nOdesl\u00e1n\u00ed zpr\u00e1vy o ud\u00e1losti (reporting) prob\u00edh\u00e1 uzlem, kter\u00fd sleduje ud\u00e1lost, p\u0159\u00edmo na SCEF (obr. 5).<\/p>\n<p><img decoding=\"async\" alt=\"NB-IoT: jak to funguje? \u010c\u00e1st 3: SCEF \u2013 jednotn\u00e9 okno pro p\u0159\u00edstup k slu\u017eb\u00e1m oper\u00e1tora\" src=\"\/wp-content\/uploads\/2019\/11\/9b385bbc324f14e1d484f1949d926b34.png\" style=\"display:block;margin: 0 auto;\" \/><br \/>\n<br \/>\n<b>D\u016fle\u017eit\u00fd bod:<\/b> ud\u00e1losti sledov\u00e1n\u00ed se mohou vztahovat jak na non-IP za\u0159\u00edzen\u00ed p\u0159ipojen\u00e1 p\u0159es SCEF, tak na IP za\u0159\u00edzen\u00ed, kter\u00e1 p\u0159ed\u00e1vaj\u00ed data klasick\u00fdm zp\u016fsobem p\u0159es MME-SGW-PGW.<\/p>\n<p>Pod\u00edvejme se podrobn\u011bji na ka\u017edou z ud\u00e1lost\u00ed sledov\u00e1n\u00ed:<\/p>\n<p><u>Ztr\u00e1ta konektivity<\/u> \u2014 informuje AS, \u017ee UE ji\u017e nen\u00ed dostupn\u00e1 pro data ani pro signaliza\u010dn\u00ed v\u00fdm\u011bnu. K t\u00e9to ud\u00e1losti dojde, kdy\u017e na MME vypr\u0161\u00ed \"mobile reachability timer\" pro UE. V \u017e\u00e1dosti o tento typ sledov\u00e1n\u00ed m\u016f\u017ee AS uv\u00e9st svou hodnotu \"Maximum Detection Time\" \u2014 pokud b\u011bhem t\u00e9to doby UE neprojev\u00ed \u017e\u00e1dnou aktivitu, AS bude informov\u00e1na, \u017ee UE nen\u00ed dostupn\u00e1, v\u010detn\u011b uveden\u00ed d\u016fvodu. K ud\u00e1losti tak\u00e9 dojde, pokud byla UE z n\u011bjak\u00e9ho d\u016fvodu n\u00e1siln\u011b odejmuta z s\u00edt\u011b.<\/p>\n<p>* Aby s\u00ed\u0165 v\u011bd\u011bla, \u017ee za\u0159\u00edzen\u00ed je st\u00e1le dostupn\u00e9, pravideln\u011b zahajuje proceduru aktualizace \u2014 Tracking Area Update (TAU). Frekvence t\u00e9to procedury je nastavena s\u00edt\u00ed pomoc\u00ed \u010dasova\u010de T3412 nebo (T3412_extended v p\u0159\u00edpad\u011b PSM), jeho\u017e hodnota je p\u0159ed\u00e1na za\u0159\u00edzen\u00ed b\u011bhem procedury Attach nebo p\u0159i dal\u0161\u00edm TAU. Mobile reachability timer je obvykle o n\u011bkolik minut del\u0161\u00ed ne\u017e T3412. Pokud UE p\u0159ed vypr\u0161en\u00edm \"Mobile reachability timer\" neprov\u00e1d\u00ed TAU, s\u00ed\u0165 ji pova\u017euje za nedostupnou. <\/p>\n<p><u>Dostupnost UE<\/u> \u2013 Ukazuje, kdy se UE st\u00e1v\u00e1 dostupnou pro DL provoz nebo SMS. K tomu doch\u00e1z\u00ed, kdy\u017e se UE st\u00e1v\u00e1 dostupnou pro paging (pro UE v re\u017eimu eDRX) nebo kdy\u017e UE p\u0159ech\u00e1z\u00ed do re\u017eimu ECM-CONNECTED (pro UE v re\u017eimu PSM nebo eDRX), tj. prov\u00e1d\u00ed TAU nebo odes\u00edl\u00e1 uplink paket.<\/p>\n<p><u>Zpr\u00e1vy o poloze<\/u> \u2013 Tento typ sledovac\u00edch ud\u00e1lost\u00ed umo\u017e\u0148uje AS po\u017e\u00e1dat o \u00fadaje o poloze UE. M\u016f\u017ee b\u00fdt po\u017eadov\u00e1na bu\u010f aktu\u00e1ln\u00ed poloha (Current Location), nebo posledn\u011b zn\u00e1m\u00e1 (Last Known Location, ur\u010duje se na z\u00e1klad\u011b cell ID, ze kter\u00e9ho za\u0159\u00edzen\u00ed posledn\u011b provedlo TAU nebo p\u0159ed\u00e1valo provoz), co\u017e je relevantn\u00ed pro za\u0159\u00edzen\u00ed nach\u00e1zej\u00edc\u00ed se v re\u017eimu \u00faspory energie PSM nebo eDRX. Pro \"Current Location\" m\u016f\u017ee AS po\u017eadovat opakovan\u00e9 zpr\u00e1vy, kdy MME bude AS informovat poka\u017ed\u00e9, kdy\u017e dojde ke zm\u011bn\u011b polohy za\u0159\u00edzen\u00ed. <\/p>\n<p><u>Zm\u011bna asociace IMSI-IMEI<\/u> \u2013 P\u0159i aktivaci t\u00e9to ud\u00e1losti SCEF za\u010d\u00edn\u00e1 sledovat zm\u011bny v vazb\u011b IMSI (identifik\u00e1tor SIM karty) a IMEI (identifik\u00e1tor za\u0159\u00edzen\u00ed). P\u0159i v\u00fdskytu ud\u00e1losti informuje AS. M\u016f\u017ee b\u00fdt pou\u017eit pro automatick\u00e9 p\u0159i\u0159azen\u00ed extern\u00edho ID k za\u0159\u00edzen\u00ed b\u011bhem pl\u00e1novan\u00fdch prac\u00ed na v\u00fdm\u011bn\u011b, nebo slou\u017eit jako identifik\u00e1tor kr\u00e1de\u017ee za\u0159\u00edzen\u00ed.<\/p>\n<p><u>Stav Roamingu<\/u> \u2013 Tento typ sledov\u00e1n\u00ed se pou\u017e\u00edv\u00e1 AS k ur\u010den\u00ed, zda se UE nach\u00e1z\u00ed v dom\u00e1c\u00ed s\u00edti, nebo v s\u00edti roamingov\u00e9ho partnera. Nepovinn\u011b m\u016f\u017ee b\u00fdt p\u0159ed\u00e1n PLMN (Ve\u0159ejn\u00e1 mobiln\u00ed s\u00ed\u0165) oper\u00e1tora, ve kter\u00e9m je za\u0159\u00edzen\u00ed registrov\u00e1no.<\/p>\n<p><u>Chyba komunikace<\/u> \u2014 Tento typ sledov\u00e1n\u00ed informuje AS o v\u00fdpadc\u00edch v komunikaci se za\u0159\u00edzen\u00edm, zalo\u017een\u00e9 na p\u0159\u00ed\u010din\u00e1ch p\u0159eru\u0161en\u00ed spojen\u00ed (release cause code) z\u00edskan\u00fdch ze s\u00edt\u011b radiov\u00e9ho p\u0159\u00edstupu (protokol S1-AP). Tato ud\u00e1lost m\u016f\u017ee pomoci ur\u010dit, pro\u010d do\u0161lo k v\u00fdpadku komunikace \u2014 z d\u016fvodu probl\u00e9m\u016f na s\u00edti, nap\u0159\u00edklad p\u0159i p\u0159et\u00ed\u017een\u00ed eNodeb (Radio resources not available), nebo z d\u016fvodu selh\u00e1n\u00ed samotn\u00e9ho za\u0159\u00edzen\u00ed (Radio Connection With UE Lost). <\/p>\n<p><u>Dostupnost po DDN chyb\u011b<\/u> \u2013 Tato ud\u00e1lost informuje AS, \u017ee za\u0159\u00edzen\u00ed je dostupn\u00e9 po selh\u00e1n\u00ed komunikace. M\u016f\u017ee b\u00fdt pou\u017eita, kdy\u017e je t\u0159eba p\u0159edat data za\u0159\u00edzen\u00ed, ale p\u0159edchoz\u00ed pokus byl ne\u00fasp\u011b\u0161n\u00fd, proto\u017ee UE nereagovalo na notifikaci od s\u00edt\u011b (paging) a data nebyla doru\u010dena. Pokud byl tento typ sledov\u00e1n\u00ed po\u017eadov\u00e1n pro UE, pak jakmile za\u0159\u00edzen\u00ed zah\u00e1j\u00ed p\u0159\u00edchoz\u00ed komunikaci, provede TAU nebo ode\u0161le data v uplinku, AS bude informov\u00e1n, \u017ee za\u0159\u00edzen\u00ed je dostupn\u00e9. Procedura DDN (downlink data notification) funguje mezi MME a S\/P-GW, tak\u017ee tento typ sledov\u00e1n\u00ed je dostupn\u00fd pouze pro IP za\u0159\u00edzen\u00ed.<\/p>\n<p><u>Stav p\u0159ipojen\u00ed PDN<\/u> \u2013 Informuje AS o zm\u011bn\u011b stavu za\u0159\u00edzen\u00ed (stav p\u0159ipojen\u00ed PDN) \u2014 p\u0159ipojen\u00ed (aktivace PDN) nebo odpojen\u00ed (odebr\u00e1n\u00ed PDN). To m\u016f\u017ee b\u00fdt pou\u017eito AS k iniciaci komunikace s UE, nebo naopak, k pochopen\u00ed, \u017ee komunikace ji\u017e nen\u00ed mo\u017en\u00e1. Tento typ sledov\u00e1n\u00ed je dostupn\u00fd pro IP i non-IP za\u0159\u00edzen\u00ed.<\/p>\n<p><u>Po\u010det UE v geografick\u00e9 oblasti<\/u> \u2013 Tento typ sledov\u00e1n\u00ed se pou\u017e\u00edv\u00e1 AS k ur\u010den\u00ed po\u010dtu UE v ur\u010dit\u00e9 geografick\u00e9 oblasti.<\/p>\n<p><b>Spou\u0161t\u011bn\u00ed za\u0159\u00edzen\u00ed (Device triggering<\/b>)<\/p>\n<p>V s\u00edt\u00edch 2G\/3G byl proces registrace do s\u00edt\u011b dvoustup\u0148ov\u00fd: nejprve se za\u0159\u00edzen\u00ed registrovalo v SGSN (proces attach), a pot\u00e9, pokud bylo pot\u0159eba p\u0159en\u00e1\u0161et data, se aktivoval PDP kontext \u2013 spojen\u00ed s paketovou br\u00e1nou (GGSN). V s\u00edt\u00edch 3G tyto dv\u011b procedury prob\u00edhaly sekven\u010dn\u011b, t.j. za\u0159\u00edzen\u00ed ne\u010dekalo na okam\u017eik, kdy m\u011blo p\u0159en\u00e1\u0161et data, ale aktivovalo PDP ihned po dokon\u010den\u00ed procedury attach. V LTE byly tyto dv\u011b procedury slou\u010deny do jedn\u00e9, co\u017e znamen\u00e1, \u017ee p\u0159i attach za\u0159\u00edzen\u00ed ihned po\u017eadovalo aktivaci PDN connection (analog PDP v 2G\/3G) p\u0159es eNodeB k MME-SGW-PGW.<\/p>\n<p>V NB-IoT je definov\u00e1n zp\u016fsob p\u0159ipojen\u00ed \u201eattach without PDN\u201c, co\u017e znamen\u00e1, \u017ee UE prov\u00e1d\u00ed attach, ani\u017e by vytvo\u0159ilo PDN spojen\u00ed. V tomto p\u0159\u00edpad\u011b nen\u00ed dostupn\u00e9 pro p\u0159enos provozu a m\u016f\u017ee pouze p\u0159ij\u00edmat nebo odes\u00edlat SMS. Aby bylo mo\u017en\u00e9 na takov\u00e9 za\u0159\u00edzen\u00ed poslat p\u0159\u00edkaz k aktivaci PDN a p\u0159ipojen\u00ed k AS, byla vyvinuta funk\u010dnost \u201eDevice triggering\u201d. <\/p>\n<p>P\u0159i obdr\u017een\u00ed p\u0159\u00edkazu na p\u0159ipojen\u00ed takov\u00e9ho UE od AS, SCEF prost\u0159ednictv\u00edm SMS centra iniciuje odesl\u00e1n\u00ed \u0159\u00edd\u00edc\u00ed SMS na za\u0159\u00edzen\u00ed. Po obdr\u017een\u00ed SMS za\u0159\u00edzen\u00ed aktivuje PDN a p\u0159ipojuje se k AS pro dal\u0161\u00ed pokyny nebo p\u0159enos dat.<\/p>\n<p>M\u016f\u017ee nastat situace, kdy na SCEF vypr\u0161\u00ed p\u0159edplatn\u00e9 na za\u0159\u00edzen\u00ed. Ano, p\u0159edplatn\u00e9 m\u00e1 svou dobu platnosti, stanovenou oper\u00e1torem nebo dohodnutou s AS. Po jeho vypr\u0161en\u00ed dojde na MME k deaktiva\u010dn\u00ed PDN a za\u0159\u00edzen\u00ed se stane nedostupn\u00fdm pro AS. V tomto p\u0159\u00edpad\u011b tak\u00e9 pom\u016f\u017ee funk\u010dnost \u201eDevice triggering\u201d. P\u0159i obdr\u017een\u00ed nov\u00fdch dat od AS SCEF zjist\u00ed stav p\u0159ipojen\u00ed za\u0159\u00edzen\u00ed a doru\u010d\u00ed data prost\u0159ednictv\u00edm SMS kan\u00e1lu.<\/p>\n<p><b>Z\u00e1v\u011br<\/b><\/p>\n<p>Funk\u010dnost SCEF se samoz\u0159ejm\u011b neomezuje na v\u00fd\u0161e popsan\u00e9 slu\u017eby a neust\u00e1le evoluuje a roz\u0161i\u0159uje. V sou\u010dasn\u00e9 dob\u011b je pro SCEF ji\u017e standardizov\u00e1no v\u00edce ne\u017e tucet slu\u017eeb. Nyn\u00ed jsme se dotkli pouze z\u00e1kladn\u00edch a \u017e\u00e1dan\u00fdch funkc\u00ed ze strany v\u00fdvoj\u00e1\u0159\u016f, o ostatn\u00edch budeme hovo\u0159it v budouc\u00edch \u010dl\u00e1nc\u00edch. <\/p>\n<p><b>Hned se nab\u00edz\u00ed ot\u00e1zka, jak z\u00edskat testovac\u00ed p\u0159\u00edstup k tomuto \u201ez\u00e1zra\u010dn\u00e9mu\u201c uzlu pro p\u0159edb\u011b\u017en\u00e9 testov\u00e1n\u00ed a lad\u011bn\u00ed mo\u017en\u00fdch p\u0159\u00edpad\u016f? V\u0161e je velmi jednoduch\u00e9. Jak\u00fdkoli v\u00fdvoj\u00e1\u0159 m\u016f\u017ee poslat \u017e\u00e1dost na iot.info@mts.ru, v n\u00ed\u017e sta\u010d\u00ed uv\u00e9st \u00fa\u010del p\u0159ipojen\u00ed, popis mo\u017en\u00e9ho p\u0159\u00edpadu a kontaktn\u00ed \u00fadaje pro spojen\u00ed.<br \/>\n<\/b><br \/>\nNa shledanou!<\/p>\n<p><i>Auto\u0159i: <\/p>\n<ul>\n<li>senior expert in convergent solutions and multimedia services Sergey Novikov <noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/users\/sanov\/\" class=\"user_link\">sanov<\/a><\/noindex>, <\/li>\n<li>expert in convergent solutions and multimedia services Alexey Lapshin <noindex><a rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/users\/aslapsh\/\" class=\"user_link\">aslapsh<\/a><\/noindex><\/li>\n<\/ul>\n<p><\/i><br \/>\n<br \/>Zdroj: <a content=\"nofollow\" rel=\"nofollow\" href=\"https:\/\/habr.com\/ru\/company\/ru_mts\/blog\/473982\/\">habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"<p>\u0412 \u0441\u0442\u0430\u0442\u044c\u0435 \u00abNB-IoT: \u043a\u0430\u043a \u043e\u043d \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442? \u0427\u0430\u0441\u0442\u044c 2\u00bb, \u0440\u0430\u0441\u0441\u043a\u0430\u0437\u044b\u0432\u0430\u044f \u043f\u0440\u043e \u0430\u0440\u0445\u0438\u0442\u0435\u043a\u0442\u0443\u0440\u0443 \u043f\u0430\u043a\u0435\u0442\u043d\u043e\u0433\u043e \u044f\u0434\u0440\u0430 \u0441\u0435\u0442\u0438 NB-IoT, \u043c\u044b \u0443\u043f\u043e\u043c\u044f\u043d\u0443\u043b\u0438 \u043f\u0440\u043e \u043f\u043e\u044f\u0432\u043b\u0435\u043d\u0438\u0435 \u043d\u043e\u0432\u043e\u0433\u043e \u0443\u0437\u043b\u0430 SCEF. \u041e\u0431\u044a\u044f\u0441\u043d\u044f\u0435\u043c \u0432 \u0442\u0440\u0435\u0442\u044c\u0435\u0439 \u0447\u0430\u0441\u0442\u0438, \u0447\u0442\u043e \u0436\u0435 \u044d\u0442\u043e \u0442\u0430\u043a\u043e\u0435 \u0438 \u0437\u0430\u0447\u0435\u043c \u044d\u0442\u043e \u043d\u0443\u0436\u043d\u043e? \u041f\u0440\u0438 \u0441\u043e\u0437\u0434\u0430\u043d\u0438\u0438 M2M-\u0441\u0435\u0440\u0432\u0438\u0441\u0430 \u0440\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a\u0438 \u043f\u0440\u0438\u043b\u043e\u0436\u0435\u043d\u0438\u0439 \u0441\u0442\u0430\u043b\u043a\u0438\u0432\u0430\u044e\u0442\u0441\u044f \u0441\u043e \u0441\u043b\u0435\u0434\u0443\u044e\u0449\u0438\u043c\u0438 \u0432\u043e\u043f\u0440\u043e\u0441\u0430\u043c\u0438: \u043a\u0430\u043a \u0438\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u0446\u0438\u0440\u043e\u0432\u0430\u0442\u044c \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432\u0430; \u043a\u0430\u043a\u043e\u0439 \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u0442\u044c \u0430\u043b\u0433\u043e\u0440\u0438\u0442\u043c \u043f\u0440\u043e\u0432\u0435\u0440\u043a\u0438 \u0438 \u043f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0438\u044f \u043f\u043e\u0434\u043b\u0438\u043d\u043d\u043e\u0441\u0442\u0438; \u043a\u0430\u043a\u043e\u0439 \u0432\u044b\u0431\u0440\u0430\u0442\u044c [&hellip;]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-52138","post","type-post","status-publish","format-standard","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.3 - aioseo.com -->\n\t<meta name=\"description\" content=\"\u0412 \u0441\u0442\u0430\u0442\u044c\u0435 \u00abNB-IoT: \u043a\u0430\u043a \u043e\u043d \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442?\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"Yuri Gagarin\"\/>\n\t<link rel=\"canonical\" href=\"https:\/\/prohoster.info\/cs\/blog\/administrirovanie\/nb-iot-kak-on-rabotaet-chast-3-scef-edinoe-okno-dostupa-k-uslugam-operatora\" \/>\n\t\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.3\" \/>\n\t\t<meta property=\"og:locale\" content=\"cs_CZ\" \/>\n\t\t<meta property=\"og:site_name\" content=\"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"\ud83e\udd47NB-IoT: \u043a\u0430\u043a \u043e\u043d \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442? 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