Tsatanetsatane wa kukhazikitsidwa kwa protocol ya PTPv2 yolumikizira nthawi

Mau oyamba

Lingaliro lomanga "Digital Substation" mumakampani amagetsi amagetsi amafuna kulumikizidwa ndi kulondola kwa 1 μs. Zochita zachuma zimafunanso kulondola kwa microsecond. M'mapulogalamuwa, kulondola kwa nthawi ya NTP sikulinso kokwanira.

PTPv2 synchronization protocol, yofotokozedwa ndi IEEE 1588v2 muyezo, imalola kulondola kwa ma nanoseconds makumi angapo. PTPv2 imakulolani kuti mutumize mapaketi olumikizana ndi L2 ndi L3 network.

Madera akuluakulu omwe PTPv2 imagwiritsidwa ntchito ndi:

• mphamvu;
• zida zowongolera ndi zoyezera;
• gulu lankhondo-mafakitale;
• telecom;
• gawo lazachuma.

Chotsatirachi chikufotokoza momwe PTPv2 synchronization protocol imagwirira ntchito.

Tili ndi chidziwitso chochuluka mumakampani ndipo nthawi zambiri timawona protocol iyi pakugwiritsa ntchito mphamvu. Chifukwa chake, tidzakambirananso mosamala za mphamvu.

Chifukwa chiyani kuli kofunikira?

Pakadali pano, STO 34.01-21-004-2019 ya PJSC Rosseti ndi STO 56947007-29.240.10.302-2020 ya PJSC FGC UES ili ndi zofunikira pakukonza basi yoyendetsera ntchito ndi kulumikizana kwa nthawi kudzera pa PTPv2.

Izi zili choncho chifukwa chakuti malo otetezera ma relay ndi zipangizo zoyezera zimagwirizanitsidwa ndi basi yoyendetsera ntchito, yomwe imatumiza nthawi yomweyo komanso mphamvu zamagetsi kudzera mu basi, pogwiritsa ntchito zomwe zimatchedwa SV mitsinje (mitsinje ya multicast).

Malo otetezedwa a relay amagwiritsa ntchito mfundozi kukhazikitsa chitetezo cha bay. Ngati kulondola kwa miyeso ya nthawi kuli kochepa, ndiye kuti chitetezo china chikhoza kugwira ntchito molakwika.

Mwachitsanzo, chitetezo cha kusankha kotheratu chikhoza kukhala chokhudzidwa ndi kugwirizanitsa nthawi "yofooka". Nthawi zambiri malingaliro a chitetezo choterocho amachokera ku kuyerekeza kwa miyeso iwiri. Ngati zikhalidwe zimasiyana ndi mtengo wokwanira, chitetezo chimayambika. Ngati zikhalidwezi ziyesedwa ndi kulondola kwa nthawi kwa 1 ms, ndiye kuti mutha kupeza kusiyana kwakukulu komwe mikhalidweyo ndi yabwinobwino ngati iyesedwa ndi kulondola kwa 1 μs.

Zithunzi za PTP

Protocol ya PTP idafotokozedwa koyamba mu 2002 mu IEEE 1588-2002 ndipo idatchedwa "Standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems." Mu 2008, ndondomeko yosinthidwa ya IEEE 1588-2008 inatulutsidwa, yomwe ikufotokoza PTP Version 2. Mtundu uwu wa protocol unawongolera kulondola ndi kukhazikika, koma sunasunge kuyanjana kwambuyo ndi ndondomeko yoyamba ya protocol. Komanso, mu 2019, mtundu wa IEEE 1588-2019 udatulutsidwa, kufotokoza PTP v2.1. Mtunduwu umawonjezera zosintha zazing'ono ku PTPv2 ndipo zimagwirizana ndi PTPv2.

Mwanjira ina, tili ndi chithunzi chotsatirachi chokhala ndi mitundu:

PTPv1
(IEEE 1588-2002)

PTPv2
(IEEE 1588-2008)

PTPv2.1
(IEEE 1588-2019)

PTPv1 (IEEE 1588-2002)

-
Zosagwirizana

Zosagwirizana

PTPv2 (IEEE 1588-2008)

Zosagwirizana

-
Zogwirizana

PTPv2.1 (IEEE 1588-2019)

Zosagwirizana

Zogwirizana

-

Koma, monga nthawi zonse, pali ma nuances.

Kusagwirizana pakati pa PTPv1 ndi PTPv2 kumatanthauza kuti chipangizo chothandizira PTPv1 sichidzatha kugwirizanitsa ndi wotchi yolondola yomwe ikuyenda pa PTPv2. Amagwiritsa ntchito mitundu yosiyanasiyana ya mauthenga kuti agwirizane.

Koma ndizothekabe kuphatikiza zida ndi PTPv1 ndi zida ndi PTPv2 pamaneti omwewo. Kuti muchite izi, opanga ena amakulolani kuti musankhe mtundu wa protocol pamadoko am'mphepete mwa wotchi. Ndiye kuti, wotchi yamalire imatha kulunzanitsa pogwiritsa ntchito PTPv2 ndikugwirizanitsa mawotchi ena olumikizidwa nayo pogwiritsa ntchito PTPv1 ndi PTPv2.

PTP zipangizo. Kodi iwo ndi otani ndipo amasiyana bwanji?

Muyezo wa IEEE 1588v2 umalongosola mitundu ingapo ya zida. Zonse zikuwonetsedwa patebulo.

Zipangizozi zimalumikizana wina ndi mnzake pa LAN pogwiritsa ntchito PTP.

Zipangizo za PTP zimatchedwa mawotchi. Mawotchi onse amatenga nthawi yeniyeni kuchokera ku wotchi ya grandmaster.

Pali mitundu 5 yamawotchi:

Wotchi ya Grandmaster

Gwero lalikulu la nthawi yolondola. Nthawi zambiri amakhala ndi mawonekedwe olumikizira GPS.

Clock Wamba

Chida chimodzi cholumikizira chomwe chingakhale mbuye (wotchi yayikulu) kapena kapolo (wotchi ya akapolo)

Master clock (master clock)

Ndiwo magwero a nthawi yeniyeni imene mawotchi ena amalunzanitsidwa

Wotchi ya akapolo

Chotsani chipangizo chomwe chimalumikizidwa kuchokera ku wotchi yayikulu

Boundary Clock

Chipangizo chokhala ndi madoko angapo omwe amatha kukhala mbuye kapena kapolo.

Ndiko kuti, mawotchiwa amatha kugwirizanitsa kuchokera ku wotchi yapamwamba kwambiri ndikugwirizanitsa mawotchi otsika a akapolo.

Mapeto mpaka-mapeto Transparent Clock

Chipangizo chokhala ndi madoko angapo chomwe sichiri wotchi yayikulu kapena kapolo. Imatumiza deta ya PTP pakati pa mawotchi awiri.

Potumiza deta, wotchi yowonekera imakonza mauthenga onse a PTP.

Kukonzaku kumachitika powonjezera nthawi yochedwetsa pa chipangizochi kumalo okonzera pamutu wa uthenga wotumizidwa.

Peer-to-Peer Transparent Clock

Chipangizo chokhala ndi madoko angapo chomwe sichiri wotchi yayikulu kapena kapolo.
Imatumiza deta ya PTP pakati pa mawotchi awiri.

Potumiza deta, wotchi yowonekera imakonza mauthenga onse a PTP Sync and Follow_Up (zambiri za iwo pansipa).

Kuwongolera kumatheka powonjezera kuwongolera kwa paketi yotumizira kuchedwa pa chipangizo chotumizira komanso kuchedwa kwa njira yotumizira deta.

Management Node

Chipangizo chomwe chimakonza ndikuzindikira mawotchi ena

Mawotchi ambuye ndi akapolo amalumikizidwa pogwiritsa ntchito masitampu anthawi mu mauthenga a PTP. Pali mitundu iwiri ya mauthenga mu protocol ya PTP:

• Mauthenga a Zochitika ndi mauthenga olumikizana omwe amaphatikizapo kupanga sitampu panthawi yomwe uthengawo watumizidwa komanso nthawi yomwe walandilidwa.
• Mauthenga Azambiri - Mauthengawa safuna masitampu anthawi, koma akhoza kukhala ndi masitampu anthawi ya mauthenga ogwirizana nawo

Mauthenga a Zochitika

Mauthenga Onse

kulunzanitsa
Delay_Req
Pdelay_Req
Pdelay_Resp

Lengezani
Londola
Delay_Resp
Pdelay_Resp_Follow_Up
Management
Kuwonetsera

Mitundu yonse ya mauthenga idzakambidwa mwatsatanetsatane pansipa.

Basic kalunzanitsidwe mavuto

Pamene paketi yolumikizira itumizidwa pa netiweki yapafupi, imachedwa pakusintha ndi ulalo wa data. Kusintha kulikonse kumabweretsa kuchedwa kwa ma microseconds pafupifupi 10, zomwe sizovomerezeka kwa PTPv2. Kupatula apo, tiyenera kukwaniritsa kulondola kwa 1 μs pa chipangizo chomaliza. (Izi ndi ngati tikukamba za mphamvu. Ntchito zina zingafunike kulondola kwambiri.)

IEEE 1588v2 imalongosola njira zingapo zogwirira ntchito zomwe zimakulolani kuti mujambule kuchedwa kwa nthawi ndikuwongolera.

Ntchito algorithm
Panthawi yogwira ntchito bwino, protocol imagwira ntchito m'magawo awiri.

• Gawo 1 - kukhazikitsa gulu la "Master Clock - Slave Clock".
• Gawo 2 - kulunzanitsa koloko pogwiritsa ntchito njira ya End-to-End kapena Peer-to-Peer.

Gawo 1 - Kukhazikitsa Utsogoleri Waukulu wa Akapolo

Doko lililonse la wotchi yokhazikika kapena yam'mphepete imakhala ndi zigawo zingapo (wotchi ya akapolo ndi wotchi yayikulu). Muyezo umafotokoza za kusintha kwa algorithm pakati pa mayiko awa. Pamapulogalamu, algorithm yotere imatchedwa finite state machine kapena state machine (zambiri mu Wiki).

Makina a boma awa amagwiritsa ntchito Best Master Clock Algorithm (BMCA) kukhazikitsa mbuye polumikiza mawotchi awiri.

Algorithm iyi imalola wotchiyo kuti itenge udindo wa wotchi ya agogo pomwe wotchi yakumtunda itaya chizindikiro cha GPS, isiya intaneti, ndi zina zambiri.

Kusintha kwa boma molingana ndi BMCA kwafupikitsidwa muzithunzi zotsatirazi:


Zambiri za wotchi yomwe ili kumapeto kwa "waya" imatumizidwa mu uthenga wapadera (Lengezani uthenga). Chidziwitsochi chikalandiridwa, algorithm yamakina a boma imathamanga ndipo kufananitsa kumapangidwa kuti muwone kuti ndi wotchi iti yomwe ili yabwinoko. Doko lomwe lili pa wotchi yabwino kwambiri limakhala wotchi yabwino kwambiri.

Ulamuliro wosavuta ukuwonetsedwa pazithunzi pansipa. Njira 1, 2, 3, 4, 5 zitha kukhala ndi wotchi yowonekera, koma satenga nawo gawo pakukhazikitsa Master Clock - Slave Clock hierarchy.

Gawo 2 - Gwirizanitsani mawotchi okhazikika komanso am'mphepete

Mukangokhazikitsa ulamuliro wa "Master Clock - Slave Clock", gawo lolumikizana la mawotchi okhazikika ndi am'malire akuyamba.

Kuti agwirizanitse, wotchi yayikulu imatumiza uthenga wokhala ndi sitampu ku mawotchi a akapolo.

The master clock ikhoza kukhala:

• siteji imodzi;
• magawo awiri.

Mawotchi agawo limodzi amatumiza uthenga umodzi Wolunzanitsa kuti alumikizitse.

Wotchi yokhala ndi magawo awiri imagwiritsa ntchito mauthenga awiri polumikizira - Sync ndi Follow_Up.

Njira ziwiri zitha kugwiritsidwa ntchito pagawo lolumikizana:

• Kuchedwetsa pempho-mayankhidwe kachitidwe.
• Njira yoyezera kuchedwa kwa anzawo.

Choyamba, tiyeni tiwone njira izi mosavuta - pamene mawotchi owonekera sagwiritsidwa ntchito.

Kuchedwetsa pempho-mayankhidwe kachitidwe

Makinawa ali ndi njira ziwiri:

1. Kuyeza kuchedwa kufalitsa uthenga pakati pa wotchi yayikulu ndi wotchi ya akapolo. Kuchitidwa pogwiritsa ntchito njira yochedwetsa-kuyankha.
2. Kuwongolera nthawi yeniyeni yosinthira kumachitika.

Muyeso wa latency


t1 - Nthawi yotumiza uthenga wa Sync ndi wotchi ya master; t2 - Nthawi yolandila uthenga wa Sync ndi wotchi ya akapolo; t3 - Nthawi yotumiza pempho lochedwa (Delay_Req) ​​ndi wotchi ya akapolo; t4 - Delay_Req nthawi yolandirira ndi master wotchi.

Pamene wotchi ya kapolo imadziwa nthawi t1, t2, t3, ndi t4, imatha kuwerengera kuchedwa kwapakati potumiza uthenga wolumikizana (tmpd). Imawerengedwa motere:

Mukatumiza uthenga wa Sync and Follow_Up, kuchedwa kwa nthawi kuchokera kwa mbuye kupita kwa kapolo kumawerengedwa - t-ms.

Mukatumiza mauthenga a Delay_Req ndi Delay_Resp, kuchedwa kwa nthawi kuchokera kwa kapolo kupita kwa mbuye kumawerengedwa - t-sm.

Ngati asymmetry ina imapezeka pakati pa zikhalidwe ziwirizi, ndiye kuti cholakwika pakukonza kupatuka kwa nthawi yeniyeni chikuwonekera. Cholakwikacho chimayamba chifukwa chakuti kuchedwa kowerengeredwa ndiko kuchedwa kwa t-ms ndi t-sm. Ngati kuchedwa sikuli kofanana, ndiye kuti sitisintha nthawi molondola.

Kukonzekera kwa nthawi yosintha

Pomwe kuchedwa pakati pa wotchi yayikulu ndi wotchi ya akapolo kumadziwika, wotchi ya akapolo imakonza nthawi.

Mawotchi a akapolo amagwiritsa ntchito uthenga wa Sync ndi uthenga wa Follow_Up wosankha kuwerengera nthawi yeniyeni yochotsera pamene mukutumiza paketi kuchokera kwa mbuye kupita ku mawotchi a akapolo. Kusintha kumawerengedwa pogwiritsa ntchito formula iyi:

Njira yoyezera kuchedwa kwa anzawo

Makinawa amagwiritsanso ntchito njira ziwiri zolumikizirana:

1. Zipangizozi zimayezera kuchedwa kwa nthawi kwa oyandikana nawo onse pamadoko onse. Kuti achite izi amagwiritsa ntchito njira yochedwa anzawo.
2. Kukonza kusintha kwa nthawi yeniyeni.

Kuyeza latency pakati pa zida zomwe zimathandizira Peer-to-Peer mode

Kuchedwetsa pakati pa madoko omwe amathandizira njira ya anzawo ndi anzawo amayezedwa pogwiritsa ntchito mauthenga awa:

Doko loyamba likadziwa nthawi t1, t1, t2 ndi t3, limatha kuwerengera kuchedwa kwapakati (tmld). Imawerengedwa pogwiritsa ntchito formula iyi:

Doko limagwiritsa ntchito mtengo uwu powerengera gawo losinthira pa uthenga uliwonse wa Sync kapena uthenga wa Follow_Up womwe umadutsa pa chipangizocho.

Kuchedwerako kudzakhala kofanana ndi kuchuluka kwa kuchedwerako panthawi yotumizira mauthenga kudzera pa chipangizochi, kuchedwa kwapakati panthawi yotumizira mauthenga kudzera mu tchanelo cha data komanso kuchedwa komwe kuli mu uthengawu, woyatsidwa pazida zam'mwamba.

Mauthenga Pdelay_Req, Pdelay_Resp ndi Pdelay_Resp_Follow_Up amakulolani kuti muchedwetsedwe kuchokera kwa mbuye kupita ku kapolo komanso kuchokera ku kapolo kupita kwa mbuye (zozungulira).

Asymmetry iliyonse pakati pazigawo ziwirizi idzayambitsa cholakwika chowongolera nthawi.

Kusintha nthawi yeniyeni yosinthira

Mawotchi a akapolo amagwiritsa ntchito uthenga wa Sync ndi uthenga wa Follow_Up wosankha kuti awerengere nthawi yeniyeni yochotsera potumiza paketi kuchokera kwa mbuye kupita ku mawotchi a akapolo. Kusintha kumawerengedwa pogwiritsa ntchito formula iyi:

Kusintha kwaubwino wamakina a anzanu ndi anzawo - kuchedwa kwa nthawi kwa uthenga uliwonse wa Sync kapena Follow_Up kumawerengeredwa momwe amafalitsidwira pa netiweki. Chifukwa chake, kusintha njira yotumizira sikungakhudze kulondola kwa kusinthako.

Mukamagwiritsa ntchito makinawa, kulunzanitsa nthawi sikufuna kuwerengera kuchedwa kwa nthawi panjira yodutsa ndi paketi yolumikizira, monga zimachitikira pakusinthanitsa koyambira. Iwo. Mauthenga a Delay_Req ndi Delay_Resp samatumizidwa. Mwanjira iyi, kuchedwa pakati pa mawotchi ambuye ndi akapolo kumangofotokozedwa mwachidule mugawo losintha la uthenga uliwonse wa Sync kapena Follow_Up.

Ubwino wina ndikuti wotchi yayikulu imachotsedwa pakufunika kokonza mauthenga a Delay_Req.

Mitundu yogwiritsira ntchito mawotchi owonekera

Motero, izi zinali zitsanzo zosavuta. Tsopano tiyerekeze kuti masiwichi akuwonekera panjira yolumikizira.

Ngati mugwiritsa ntchito masiwichi popanda thandizo la PTPv2, paketi yolumikizira idzachedwetsedwa pa switch ndi pafupifupi 10 μs.

Mawotchi omwe amathandizira PTPv2 amatchedwa Mawotchi Owonekera mu IEEE 1588v2 terminology. Mawotchi owoneka bwino samalumikizidwa kuchokera ku wotchi yayikulu ndipo satenga nawo gawo pagulu la "Master Clock - Slave Clock", koma akamatumiza mauthenga amalumikizidwe amakumbukira kuti uthengawo udachedwetsedwa nthawi yayitali bwanji. Izi zimakuthandizani kuti musinthe kuchedwa kwa nthawi.

Mawotchi owonekera amatha kugwira ntchito m'njira ziwiri:

• Mapeto mpaka Mapeto.
• Pachinzawo.

Mapeto mpaka Mapeto (E2E)

Wotchi yowonekera ya E2E imawulutsa mauthenga a Sync ndi mauthenga otsagana ndi Follow_Up pamadoko onse. Ngakhale omwe atsekeredwa ndi ma protocol ena (mwachitsanzo, RSTP).

Kusinthaku kumakumbukira nthawi yomwe paketi ya Sync (Follow_Up) idalandiridwa padoko komanso pomwe idatumizidwa kuchokera padoko. Kutengera masitampu awiriwa, nthawi yomwe imatengera kusintha kwa uthengawo imawerengedwa. Muyeso, nthawiyi imatchedwa nthawi yokhalamo.

Nthawi yokonza imawonjezedwa kugawo la kukonzaField la Sync (wotchi imodzi) kapena Follow_Up (masitepe awiri) uthenga.

Wotchi yowonekera ya E2E imayesa nthawi yosinthira mauthenga a Sync ndi Delay_Req akudutsa pa switch. Koma ndikofunikira kumvetsetsa kuti kuchedwa kwa nthawi pakati pa wotchi yayikulu ndi wotchi ya akapolo kumawerengeredwa pogwiritsa ntchito njira yochedwetsa-kuyankha. Ngati wotchi yayikulu isintha kapena njira yochokera ku wotchi yayikulu kupita ku wotchi yaukapolo ikusintha, kuchedwa kumayesedwanso. Izi zimawonjezera nthawi yosinthira ngati maukonde asintha.

Wotchi yowonekera ya P2P, kuwonjezera pakuyesa nthawi yomwe imatengera kusinthana kuti uthenga usinthe, imayesa kuchedwa kwa ulalo wa data kwa mnansi wake wapafupi pogwiritsa ntchito makina ochezera oyandikana nawo.

Kuchedwa kumayesedwa pa ulalo uliwonse mbali zonse ziwiri, kuphatikiza maulalo omwe atsekeredwa ndi ma protocol ena (monga RSTP). Izi zimakupatsani mwayi wowerengera nthawi yomweyo kuchedwa kwatsopano munjira yolumikizira ngati wotchi ya grandmaster kapena topology ya netiweki isintha.

Nthawi yokonza mauthenga ndi masinthidwe ndi latency amawunjikana potumiza mauthenga a Sync kapena Follow_Up.

Mitundu ya chithandizo cha PTPv2 ndi ma switch

Kusintha kumatha kuthandizira PTPv2:

• mwadongosolo;
• hardware.

Mukakhazikitsa protocol ya PTPv2 mu pulogalamu, chosinthiracho chimapempha sitampu yanthawi kuchokera ku firmware. Vuto ndilakuti firmware imagwira ntchito mozungulira, ndipo muyenera kudikirira mpaka imalize kuzungulira kwapano, kutenga pempho lokonzekera ndikutulutsa sitampu pambuyo pa kuzungulira kotsatira. Izi zidzatenganso nthawi, ndipo tidzachedwa, ngakhale sizofunika kwambiri ngati popanda thandizo la mapulogalamu a PTPv2.

Thandizo la hardware lokha la PTPv2 limakupatsani mwayi kuti mukhalebe olondola. Pankhaniyi, sitampu ya nthawi imaperekedwa ndi ASIC yapadera yomwe imayikidwa padoko.

Mtundu wa Mauthenga

Mauthenga onse a PTP ali ndi magawo awa:

• Mutu - 34 byte.
• Thupi - kukula kumadalira mtundu wa uthenga.
• Suffix ndizosankha.

chamutu

Munda wa Header ndi womwewo pa mauthenga onse a PTP. Kukula kwake ndi 34 bytes.

Mtundu wapamutu:

messageType - ili ndi mtundu wa uthenga womwe ukufalitsidwa, mwachitsanzo Sync, Delay_Req, PDelay_Req, etc.

uthengaLength - ili ndi kukula kwathunthu kwa uthenga wa PTP, kuphatikiza mutu, thupi ndi suffix (koma osaphatikiza padding byte).

domainNumber - imatsimikizira kuti uthenga wa PTP ndi uti.

Kasitomala - awa ndi mawotchi angapo osiyanasiyana omwe amasonkhanitsidwa mu gulu limodzi lomveka bwino ndikulumikizidwa kuchokera ku wotchi yayikulu imodzi, koma osati kulumikizidwa ndi mawotchi amtundu wina.

mbendera - Mundawu uli ndi mbendera zosiyanasiyana kuti adziwe momwe uthengawo ulili.

kukonzaMunda - ili ndi nthawi yochedwa mu nanoseconds. Nthawi yochedwa imaphatikizapo kuchedwa potumiza wotchi yowonekera, komanso kuchedwa potumiza tchanelo mukamagwiritsa ntchito Peer-to-Peer mode.

sourcePortIdentity - gawoli lili ndi chidziwitso cha doko lomwe uthengawu unatumizidwa koyambirira.

sequenceID - ili ndi nambala yozindikiritsa mauthenga amodzi.

controlField - artifact field =) Imakhalabe kuchokera ku mtundu woyamba wa muyezo ndipo ili ndi zambiri za mtundu wa uthengawu. Zofanana ndi messageType, koma ndi zosankha zochepa.

logMessageInterval - gawo ili limatsimikiziridwa ndi mtundu wa uthenga.

thupi

Monga tafotokozera pamwambapa, pali mitundu ingapo ya mauthenga. Mitundu iyi ikufotokozedwa pansipa:

Uthenga wolengeza
Mauthenga a Lengeza amagwiritsidwa ntchito "kuwuza" mawotchi ena omwe ali mudera lomwelo za magawo ake. Uthengawu umakulolani kukhazikitsa Master Clock - Slave Clock hierarchy.


Lunzanitsa uthenga
Uthenga wa Sync umatumizidwa ndi master clock ndipo uli ndi nthawi ya master wotchi panthawi imene uthenga wa Sync unapangidwa. Ngati wotchi yayikulu ili ndi magawo awiri, ndiye kuti chosindikizira chanthawi mu uthenga wa Sync chidzakhazikitsidwa ku 0, ndipo chosindikizira chapano chidzatumizidwa muuthenga wogwirizana nawo. Mauthenga a Sync amagwiritsidwa ntchito panjira zonse zoyezera latency.

Uthengawu umafalitsidwa pogwiritsa ntchito Multicast. Mukasankha mutha kugwiritsa ntchito Unicast.

Delay_Req uthenga

Mtundu wa uthenga wa Delay_Req ndi wofanana ndi uthenga wa Sync. Wotchi ya akapolo imatumiza Delay_Req. Ili ndi nthawi yomwe Delay_Req idatumizidwa ndi wotchi ya akapolo. Uthengawu umangogwiritsidwa ntchito pongochedwetsa kuyankha.

Uthengawu umafalitsidwa pogwiritsa ntchito Multicast. Mukasankha mutha kugwiritsa ntchito Unicast.

Uthenga_wotsatira

The Follow_Up meseji imatumizidwa ndi wotchi yayikulu ndipo imakhala ndi nthawi yotumiza Lunzanitsa mauthenga mbuye. Mawotchi akuluakulu a magawo awiri okha amatumiza uthenga wa Follow_Up.

The Follow_Up message is used for all the latency measurement.

Uthengawu umafalitsidwa pogwiritsa ntchito Multicast. Mukasankha mutha kugwiritsa ntchito Unicast.

Delay_Resp message

Uthenga wa Delay_Resp umatumizidwa ndi master clock. Ili ndi nthawi yomwe Delay_Req idalandiridwa ndi wotchi yayikulu. Uthengawu umangogwiritsidwa ntchito pongochedwetsa kuyankha.

Uthengawu umafalitsidwa pogwiritsa ntchito Multicast. Mukasankha mutha kugwiritsa ntchito Unicast.

Pdelay_Req uthenga

Uthenga wa Pdelay_Req umatumizidwa ndi chipangizo chomwe chimapempha kuchedwa. Ili ndi nthawi yomwe uthengawo unatumizidwa kuchokera padoko la chipangizochi. Pdelay_Req imagwiritsidwa ntchito poyezera kuchedwa kwa mnansi.

Pdelay_Resp message

Uthenga wa Pdelay_Resp umatumizidwa ndi chipangizo chomwe chalandira pempho lochedwa. Ili ndi nthawi yomwe uthenga wa Pdelay_Req udalandiridwa ndi chipangizochi. Uthenga wa Pdelay_Resp umagwiritsidwa ntchito pongoyezera kuchedwa kwa mnansi.

Uthenga Pdelay_Resp_Follow_Up

Uthenga wa Pdelay_Resp_Follow_Up umatumizidwa ndi chipangizo chomwe chalandira pempho lochedwa. Ili ndi nthawi yomwe uthenga wa Pdelay_Req udalandiridwa ndi chipangizochi. Uthenga wa Pdelay_Resp_Follow_Up umangotumizidwa ndi mawotchi akuluakulu a magawo awiri.

Uthengawu utha kugwiritsidwanso ntchito ngati nthawi yochitira m'malo molemba nthawi. Nthawi yoperekera ndi nthawi kuyambira pomwe Pdelay-Req idalandiridwa mpaka Pdelay_Resp itatumizidwa.

Pdelay_Resp_Follow_Up amagwiritsidwa ntchito poyezera kuchedwa kwa mnansi.

Mauthenga Otsogolera

Mauthenga owongolera a PTP amafunikira kusamutsa chidziwitso pakati pa wotchi imodzi kapena zingapo ndi node yolamulira.

Kusamutsa ku LV

Uthenga wa PTP ukhoza kufalitsidwa pamagulu awiri:

• Network - monga gawo la IP data.
• Channel - monga gawo la chimango cha Ethernet.

Kutumiza uthenga wa PTP kudzera pa UDP kudzera pa IP kudzera pa Ethernet

PTP pa UDP pa Ethernet

Mbiri

PTP ili ndi magawo ambiri osinthika omwe amafunika kukonzedwa. Mwachitsanzo:

• Zosankha za BMCA.
• Njira yoyezera kuchedwa.
• Zosintha ndi zoyambira zamagawo onse osinthika, etc.

Ndipo ngakhale tidanena kale kuti zida za PTPv2 zimagwirizana, izi sizowona. Zipangizo ziyenera kukhala ndi zochunira zomwezo kuti zizilumikizana.

Ichi ndichifukwa chake pali otchedwa mbiri ya PTPv2. Mbiri ndi magulu a zoikamo kukhazikitsidwa ndi zoletsedwa protocol kumatanthauza kuti nthawi kalunzanitsidwe akhoza kukhazikitsidwa kwa ntchito inayake.

Muyezo wa IEEE 1588v2 wokha umafotokoza mbiri imodzi yokha - "Default Profile". Mbiri zina zonse zimapangidwa ndikufotokozedwa ndi mabungwe ndi mabungwe osiyanasiyana.

Mwachitsanzo, Power Profile, kapena PTPv2 Power Profile, idapangidwa ndi Power Systems Relaying Committee ndi Substation Committee ya IEEE Power and Energy Society. Mbiri yokha imatchedwa IEEE C37.238-2011.

Mbiriyi ikufotokoza kuti PTP ikhoza kusamutsidwa:

• Pokhapokha kudzera pa L2 network (ie Ethernet, HSR, PRP, non-IP).
• Mauthenga amafalitsidwa kokha ndi Multicast kuwulutsa.
• Njira yoyezera kuchedwa kwa anzawo imagwiritsidwa ntchito ngati njira yoyezera mochedwa.

Demain yokhazikika ndi 0, domain yovomerezeka ndi 93.

Filosofi ya mapangidwe a C37.238-2011 inali kuchepetsa chiwerengero cha zinthu zomwe mungasankhe ndikusunga ntchito zofunikira zokhazokha zokhudzana ndi mgwirizano wodalirika pakati pa zipangizo ndi kuwonjezereka kwa dongosolo lokhazikika.

Komanso, kuchuluka kwa mauthenga kumatsimikiziridwa:

M'malo mwake, gawo limodzi lokha likupezeka pakusankhidwa - mtundu wa wotchi ya master (gawo limodzi kapena magawo awiri).

Kulondola sikuyenera kupitirira 1 μs. Mwanjira ina, njira imodzi yolumikizira imatha kukhala ndi mawotchi owoneka bwino a 15 kapena mawotchi atatu am'malire.

Source: www.habr.com