Classes na IP-adiresoshin. IP-adiresoshin na aji A, B, C

IP - shi ne mai yarjejeniya, wanda aka yi amfani da mafi kananan cibiyar sadarwa na biyu da na'urorin ga duniya bayanai cibiyar sadarwa. IP-address - wani farɗan mai ganowa don wani musamman kumburi (na'ura), kasaftawa zuwa wasu cibiyar sadarwa.

Recording IP address-

Address kama wani 32-bit lamba a cikin kewayon daga 0 to 4294967295. Wannan yana nufin cewa a ko'ina cikin Internet iya ƙunsar fiye da biliyan 4 na musamman adiresoshin gaba daya wurare. Idan rikodin adiresoshin a binary ko gidan goma tsari, shi sa su rashin jin daɗi a cikin haddar ko aiki. Saboda haka, ya rage wuya rubuce-rubuce na wadannan adiresoshin, an yanke shawarar raba cikakken adireshin a cikin gidan takwas (8-bit yawan), rabu da wani dot. Ga misali: da adireshin wanda a Hex kama S0290612, rikodin IP-adiresoshin zai yi kama da 192.41.6.18. A wannan yanayin, mafi ƙasƙanci adireshin - wannan shi ne hudu zeros, kuma matsakaicin - hudu kungiyoyin na 255. Babbansu area (wanda ake located a gefen hagu kungiyoyin na Figures daga wani daga cikin rarraban maki) sun shagaltar da adireshin wuri, ƙarami area (a gefen dama daga cikin guda division batu ) ya nuna da yawan da ke dubawa a kan cewa cibiyar sadarwa. A matsayi na iyaka tsakanin rundunar da kuma cibiyar sadarwa ~ angare ke dogara da yawan ragowa da aka dauka zuwa cibiyar sadarwa mai lamba ne daban-daban, da rabuwa ne kawai wani bane iyaka (batu tsakanin su), kuma ba ka damar ayyana azuzuwan na IP-adiresoshin.

Class model adiresoshin

Da dama da suka gabata adireshin an raba cikin 5 azuzuwan. Yana kare a lokacin, da rabo ne ake kira magance polnoklassovoy. Classes na IP-adiresoshin ake kira haruffa daga cikin haruffa daga A zuwa E. The azuzuwan A to E sa shi yiwuwa a saka identifiers for 128 networks da miliyan 16 na cibiyar sadarwa musaya kowane, 16.384 cibiyar sadarwa na'urorin da 64 dubu da miliyan 2 networks da 256 musaya. IP-tushen networks Classes D ana azurta multicasting, a cikin abin da saƙon fakitoci aka aika zuwa mahara Runduna lokaci guda. Adiresoshin cewa da farko ragowa 1111 aka tanada nan gaba amfani.

Kasa ne a tebur na IP-adiresoshin. Classes ake tsare da m adireshin ragowa.

aji A

IP-adiresoshin na aji A halin da manyan sifili bit da takwas-bit adireshin size na ga cibiyar sadarwa. Rubuta a cikin hanyar:

Haka kuma, mafi girma yawan Class A networks iya zama 2 ^7, amma kowanne daga cikinsu zai sami wani adireshin sarari na ^{24 Fabrairu} na'urorin. Tun da farko bit na adireshin ne 0, to, duk da IP-address na aji A za a high-domin bane kewayon daga 0 zuwa 127, wanda, haka ma, zai zama cibiyar sadarwa da kuma lambar. A wannan yanayin, da sifili adireshin da 127 aka tanada kasuwanci adireshin, don haka ba za su iya amfani da shi. Saboda wannan dalili, daidai yawan Class A networks karkacewa 126.

A karkashin kumburi adireshin a cikin aji A cibiyar sadarwa sanya 3 bytes (ko 24 ragowa). Simple lissafi ya nuna cewa, yana yiwuwa ya sanya 16777216 binary haduwa (dubawa adiresoshin). Tun da adiresoshin kunsha gaba ɗaya na zeros da su, suna na musamman, sa'an nan aji A cibiyar sadarwa yawan an rage wa 16.777.214 adiresoshin.

Classes B da C

Babban bayãnin hukuncin alama na Class b IP-address zai kasance da tamanin da biyu mafi muhimmanci ragowa daidai 10. The size na cibiyar sadarwa bangare ne daidai da 16 ragowa. The format na cibiyar sadarwa ne kamar haka:

A saboda wannan dalili, mafi girma yawan aji B cibiyar sadarwa zai iya zama 2 ¹⁴ (16384) da wani adireshin sarari a kan Fabrairu ¹⁶ kowannensu. IP-adiresoshin na aji B tashi a wata fuska daga 128 zuwa 191. Shi ne mai alama ta abin da za ka iya sanin ko cibiyar sadarwa na zuwa cewa aji. Biyu bytes, kaddamarda da adiresoshin waɗannan hanyoyin sadarwa, debe sifili da ya kunshi raka'a adiresoshin iya sa yawan nodes daidai 65.534.

Duk wani IP-address ne Class C zai fara a cikin kewayon daga 192 zuwa 223, tare da cibiyar sadarwa mai lamba bautar da uku manyan bane. Schematically adireshin yana da wadannan tsarin:

Uku na farko ragowa ne 110, 24-bit cibiyar sadarwa rabo. The most yawan cibiyoyin sadarwa a cikin wannan aji ne ^{21 Fabrairu} (wannan shi ne 2,097,152 net). A karkashin kumburi adireshin a cikin IP-address na aji C networks da 1 byte, shi ne 254 Runduna.

Ƙarin cibiyar sadarwa azuzuwan

A D kuma E azuzuwan hada da cibiyar sadarwa da mafi bane sama 224. Wadannan adireshin aka tanada musamman dalilai kamar, misali, multicasting - watsa datagrams zuwa takamaiman kungiyoyin na nodes a cikin cibiyar sadarwa.

Class D iyaka da ake amfani da aika fakitoci kuma qarya a cikin kewayon daga 224.0.0.0 zuwa 239.255.255.255. Last aji E kẽɓantacce ne ga nan gaba amfani. Yana hada da adireshin 240.0.0.0 zuwa 255.255.255.255. Saboda haka, idan ba ka so matsaloli tare da magance, shi ne bu mai kyau ba su dauki IP-adiresoshin daga wadannan jeri.

Reserved IP-adiresoshin

Akwai adireshin da cewa ba za a iya bai wa kõwa na'urorin, abin da IP-magance. Tools IP-adireshin da wani qayyadadden dalili. Alal misali, idan cibiyar sadarwa adireshin kunshi zeros, yana nufin cewa da kumburi yana nufin halin yanzu cibiyar sadarwa ko wani kashi. Idan duk raka'a - da cewa shi ne address for watsa shirye-shirye fakitoci mailings.

A ajin A, akwai biyu musamman kwazo cibiyar sadarwa da lambobin 0 kuma 127. A adireshin sifili da ake amfani da matsayin tsoho hanya, da kuma 127 nuna magance to kanta (da loopback dubawa). Alal misali, lura da IP 127.0.0.1 yana nufin cewa kumburi na Magana ne kawai tare da kanta ba tare da tafiyarsu datagrams a kan wani data matsakaici. Domin da kai Layer connection ne ba daban-daban daga dangane da m rundunar, don haka a loopback adireshin ne sau da yawa amfani da su gwada cibiyar sadarwa software.

Ma'ana cibiyar sadarwa IDs kuma rundunar

Sanin IP-address na na'urar a cikin akwati inda akwai wata tambaya game da yadda za a ƙayyade da aji na IP-address, sa'an nan kawai dubi farko bane na imel. Idan shi ne 1 ga 126, wannan aji A cibiyar sadarwa, daga 128 zuwa 191 - wani Class B cibiyar sadarwa, daga 192 zuwa 223 - cibiyar sadarwa aji C.

Don gane da cibiyar sadarwa kamata a tuna cewa a cikin A aji ne farawa da lambar a cikin IP-address to B - da farko biyu lambobi a cikin C - na farko uku lambobi. Sauran su ne identifiers na cibiyar sadarwa musaya (nodes). Alal misali, IP-address ne adireshin 139.17.54.23 aji B, tun da farko lamba - 139 - mafi girma daga 128 da kasa da 191. Saboda haka, sadarwa ganowa ne daidai 139.17.0.0, kumburi ganowa - 54,23.

subnet

Da taimakon magudanar da kuma gadoji da damar fadada your cibiyar sadarwa ta ƙara segments to shi, ko raba shi a cikin karami subnet ta canza hanyar sadarwa ID. A wannan yanayin dauka subnet mask cewa, ya nuna wanda kashi IP-address za a yi amfani da matsayin ganowa na sabon subnet. Lokacin da IDs ne guda, za ka iya kammala da cewa, nodes kasance a cikin wannan subnet, in ba haka ba za su kasance a cikin wani daban-daban subnet da na'ura mai ba da hanya tsakanin hanyoyin sadarwa bukatar gama su.

IP-adiresoshin azuzuwan da aka tsara don haka da cewa ga wani yawan Networking shafukan da ayyana a gaba. By tsoho, kungiyar za ta tura kawai guda cibiyar sadarwa da yawan cibiyar sadarwa-da alaka da na'urorin. Akwai wasu cibiyar sadarwa ganowa da kuma yawan nodes ciwon ƙuntatawa daidai da cibiyar sadarwa aji. Tare da babban adadin nodes cibiyar sadarwa zai zama low bandwidth, domin ko da wani watsa shirye-shirye cika zai fada.

subnet masks

Domin raba ID, dole ne ka yi amfani da subnet mask - mai juna da cewa taimaka wajen rarrabe cibiyar sadarwa ID daga kumburi identifiers a cikin IP-adiresoshin. Classes IP-address ba Ya kãmã hani a kan subnet mask. Rufe fuska da azahiri dubi guda a matsayin adireshin - hudu kungiyoyin na lambobin daga 0 zuwa 255. A wannan yanayin, a farko akwai manyan lambobi na su karami. Alal misali, 255.255.248.0 - wannan shi ne daidai subnet mask, 255.248.255.0 - ba daidai ba. Mask 255.255.255.0 ma'anar farko uku octets na IP-address matsayin subnet ID.

A lokacin da zayyana wani sha'anin sadarwa rabawa na bukatar cewa IP-magance da aka shirya daidai. Classes na IP-adiresoshin, rabu cikin segments ta wajen masks, ba zai iya kawai ƙara yawan kwamfutocin a kan hanyar sadarwa, amma kuma don tsara ta yi. Kowane aji na da wani adireshin mask na cibiyar sadarwa da tsoho.

babu default mask ne sau da yawa amfani ƙarin subnets da kuma mutum. Alal misali, IP-address 170.15.1.120 iya amfani da subnet mask 255.255.255.0 zuwa cibiyar sadarwa ID 170.15.1.0, ba lallai ba ne su yi amfani da subnet mask na 255.255.0.0 da ID 170.15.0.0, wanda shine tsoho. Wannan ba ka damar raba wani data kasance ƙungiya Class B cibiyar sadarwa da ID 170.15.0.0 subnets yin amfani da daban-daban masks.

Lissafi na subnets sigogi

Bayan subnet saituna a kan kowane software ke dubawa cibiyar sadarwa yarjejeniya za su gudanar da wani binciken na IP-adiresoshin amfani da wani subnet mask domin sanin subnet address. Akwai biyu sauki dabarbari for kirga matsakaicin yawan subnets da rundunõninsa a kan hanyar sadarwa:

• 2 ^{(yawan ragowa daidaita daya a wani mask)} - 2 = mafi girma yawan subnets.
• 2 ^{(adadin zeros a subnet mask)} - 2 = matsakaicin yawan na'urorin a kan wani subnet.

Alal misali, sama da adireshin daidai 182.16.52.10 tare da mask 255.255.224.0. Mask a binary kama da wannan: 11111111.11111111.11100000.00000000. Kuna hukunta da farko bane ne cibiyar sadarwa nasa ne da aji B, saboda haka, mun yi la'akari da uku da ta huɗu gidan takwas ba. Uku raka'a goma sha uku da kuma zeros a cikin dabara da kuma samun 23-2 = 6 subnets da kuma 213 - 2 = 8190 Runduna.

Lokacin da ake ji da misali cibiyar sadarwa aji B a matsayin mask 255.255.255.0 65534 cibiyar sadarwa iya riskar na'urorin. Idan subnet address byte bautarka cikakken kumburi, sa'an nan yawan alaka da na'urorin a kowane subnetwork an rage wa 254. Lokacin da shi wajibi ne don ƙetare yawan na'urorin za a iya matsaloli warware ta rage saura subnet mask adireshin ko Bugu da kari na wani sakandare adireshin da na'ura mai ba da hanya tsakanin hanyoyin sadarwa dubawa. Amma a wannan yanayin, rage yawan yiwu networks za a kiyaye.

Idan ka ƙirƙiri subnets a wani aji C cibiyar sadarwa, sani cewa zabi zai zama kadan, tare da free daya kawai bane. Lokacin da sifting sifili da kuma watsa shirye-shirye adireshin ne da yiwuwar samar da hudu sets daga cikin mafi kyau zabin subnets: daya subnet za ta karbi bakuncin 253, biyu subnet 125 Runduna hudu subnets a kan 61 rundunar takwas subnets na 29 Runduna. Sauran bambance-bambancen karatu da bangare zai haifar da matsaloli a cikin bayar da kwatance da kuma watsa shirye-shiryen ko kawai hanyar cikas a cikin lissafi na magance tsakanin Runduna.

Samar da wata subnet a aji B networks ya fi sauƙi, a matsayin mafi 'yancin zabi. The default subnet mask ne 255.255.0.0, yayin da yin amfani da shi samun wani 65534 rundunar. A lokacin da samar masks karkashin su subnet adiresoshin ake kasaftawa daga bar untagged ragowa 3 da 4 gidan takwas ba. Za a iya samu ta hanyar lissafi mafi kyau duka cibiyar sadarwa da lambobin 32, 64, 96, 128, 160 da kuma 192.

Class A cibiyar sadarwa yana da manya-manyan yawan adiresoshin, to wanda shi ne yiwu ya halicci subnet. Domin amfani subnet masks za a iya amfani up to 32 ragowa. Amfani da sama dabara, za mu iya sanin ko matsakaicin yawan subnets cewa zai iya zama har zuwa 254. A daidai wannan lokaci a kan rundunar adireshin ne 16 ragowa, shi ne zai yiwu a haɗa 65534 nodes.

Hakika, wannan shi ne kawai m lissafin. A lokacin da samar sassa da kuma tare da subnetting wajibi ne a yi la'akari da mafi dalilai, wanda ke dogara a kan bada da kuma sha'anin matakin.