IPV4 packet format

(1)The versionfield accounts for 4 bits, zvichiratidza shanduro ye IP protocol.
(2)IP Header Length, munda uyu unoshandiswa kutsanangura kureba kweiyo IP musoro, sezvo kune kusiyanisa kureba zvingasarudzwa zvikamu mumusoro weIP. Ichi chikamu chinotora 4 bits, ine hurefu yuniti ye4 bytes, izvo zvinoreva kuti kukosha munharaunda ino = IP musoro wehurefu (mumabhayiti) / urefu unit (4 bytes).
(3)Rudzi rweSevhisi: 8 bits pakureba.
PPP: Nhamba nhatu dzekutanga dzinotsanangura kukosha kwepakeji. Iyo inonyanya kukosha kukosha, iyo inonyanya kukosha iyo Big data iri
000 (Routine) Normal
001 (Yekutanga) yekutanga, inoshandiswa kune data bhizinesi
010 (Immediate) ipapo, yebhizinesi redata
011 (Flash) flash kumhanya yekufambisa izwi
100 (Flash Overrides) nekukurumidza kune vhidhiyo bhizinesi
101 (yakakosha) CRI/TIC/ECP yakakosha pakufambisa kwezwi
110 (Internet Control) Inter network control, inoshandiswa kudzora network, senge nzira dzeprotocol
111 (Network Control) network control, inoshandiswa kudzora network
DTRCO: Ekupedzisira manhamba mashanu
(1000) D kunonoka: 0: min kunonoka, 1: kuderedza kunonoka sezvinobvira
(0100) T Kubuditsa: 0: max throughput (maximum throughput), 1: Edza kuwedzera traffic zvakanyanya sezvinobvira
(0010) R kuvimbika: 0: max throughput, 1: wedzera kuvimbika
(0001) M mutengo wekutumira: 0: min Muvhuro mutengo (ishoma nzira pamusoro), 1: dzikisa mutengo zvakanyanya sezvinobvira
(0000): zvakajairika (nguva dzose sevhisi).
(4)Hurefu hwese hweIP packet: 16 bits pakureba. Kureba kweIP packet yakaverengerwa mumabhaiti (kusanganisira musoro uye data), saka kureba kweIP packet ndeye 65 535 bytes. Saka, saizi yepakiti payload=Yakazara IP packet urefu - IP musoro wehurefu.
(5)Identifier: 16 bits pakureba. Iyi ndima inoshandiswa pamwe chete neMireza uye Fragment Offer minda kupatsanura makuru epamusoro epacket. Mushure merouterkupatsanura pakiti, ese madiki mapaketi akapatsanurwa anoiswa chiratidzo cheukoshi hwakafanana, kuitira kuti mudziyo wekuenda unogona kusiyanisa kuti ndeipi pakiti ndeyepaketi yakakamurwa.
(6)Mireza: 3 bits pakureba.
Nhamba yekutanga yendima iyi haina kushandiswa.
Chechipiri chidimbu iDF (Usaite Chimedu) bit. Kana iyo DF bit ikaiswa ku1, inoratidza kuti iyorouterhaigone kugovera iyo yepamusoro layer packet. Kana pakiti yepamusoro isingakwanise kuendeswa mberi pasina kupatsanurwa, iyorouterinorasa iyo yepamusoro layer packet uye inodzosera meseji yekukanganisa.
Chechitatu bhiti iMF (Zvimedu Zvimwe) bit. Apo iyorouterzvikamu zvepaketi yepamusoro, inoisa iyo MF bit kusvika 1 mumusoro weIP packet kunze kwechikamu chekupedzisira.
(7)Fragment Offset: Hurefu hwemabhiti gumi nematatu, akayerwa muzvikamu zve8 octets. Inoratidza nzvimbo ye IP packet muchikamu chechikamu, iyo inoshandiswa nekuguma kwekugamuchira kuunganidza uye kudzorera IP packet.
(8)Nguva yekurarama (TTL): Hurefu i8 bits, yakatanga kugadzirwa mumasekonzi (s), asi ichipimwa nemahops. Iyo yakakurudzirwa yakasarudzika kukosha ndeye 64. Apo IP packets inotumirwa, yakakosha kukosha kunotanga kupihwa kune iyi ndima. Kana IP packet ichipfuura neimwe neimweroutermunzira, mumwe nomumweroutermunzira ichaderedza kukosha kweTTL ye IP packet ne 1. Kana TTL yakaderedzwa kusvika 0, IP packet icharaswa. Iyi ndima inogona kudzivirira IP mapaketi kuti arege kuramba achiendeswa kunetiweki nekuda kwenzira dzenzira.
(9)Protocol: 16 bits pakureba. Inoshandiswa kuonesa kurongeka kweiyo IP misoro, asi haisanganisire data chikamu. Nokuti mumwe nomumwerouterinoda kushandura kukosha kweTTL, iyorouterichaverengerazve kukosha uku papakiti yega yega inopfuura
(10)Header Checksum: 16 bits pakureba. Inoshandiswa kuonesa kurongeka kweiyo IP misoro, asi haisanganisire data chikamu. Nokuti mumwe nomumwerouterinoda kushandura kukosha kweTTL, iyorouterichaverengerazve kukosha uku papakiti yega yega inopfuura
(11)Kwakabva uye Kero Yekwaunoenda: Kero dzese dziri 32 bits. Inozivisa kwakabva uye kero yekwainoenda yeiyi IP packet. Ndokumbira utarise kuti kunze kwekunge NAT ikashandiswa, kero mbiri idzi hadzishanduke mukati mese nzira yekutapurirana.
(12)Options: Iyi inzvimbo yehurefu hwakasiyana. Iyi ndima ndeyekusarudza uye inonyanya kushandiswa kuyedza, uye inogona kunyorwazve nemudziyo wekutanga sezvinodiwa. Zvinhu zvinosarudzwa zvinosanganisira zvinotevera:

•Lose source routing: Ipa nhevedzano ye IP kero yerouterinterfaces. IP mapaketi anofanirwa kufambiswa pamwe neaya IP kero, asi inotenderwa kusvetuka akawanda ma routers pakati peaviri akateedzana IP kero.
•Strict source routing: Ipa nhevedzano ye IP kero yerouterinterfaces. IP mapaketi anofanirwa kufambiswa pamwe neaya IP kero, uye kana inotevera hop isiri muIP kero tafura, inoratidza kukanganisa.
•Rekodha nzira: Rekodha IP kero yeiyo router inobuda interface kana IP packet ichisiya imwe neimwerouter.
•Zvitambi zvenguva: Rekodha nguva iyo IP pakiti inosiya imwe neimwerouter.
•Padding: Nekuti iyo unit ye ​​IP header kureba i32 bits, kureba kwemusoro weIP kunofanirwa kunge kwakawanda kwe32 bits. Naizvozvo, mushure mesarudzo yesarudzo, IP protocol inozadza mazero akati wandei kuti iwane nhamba yakawanda ye32 bits.
IPV4 data inogona kazhinji kuiswa kune yekambani yeduONUnetwork zvishandiso, uye yedu ine hukama netiweki inopisa kutengesa zvigadzirwa zvinofukidza akasiyana marudzi eONUakatevedzana zvigadzirwa, kusanganisira ACONU/kutauriranaONU/akangwaraONU/bhokisiONU, etc. Zviri pamusoro apaONUseries zvigadzirwa zvinogona kushandiswa kunetiweki zvinodiwa mumamiriro akasiyana siyana. Gamuchirai munhu wese kuti auye kuzova neruzivo rwakadzama rwehunyanzvi hwekunzwisisa kwechigadzirwa.