Wataƙila kun ji labarin NAT ana magana a kan fannin haɗin gwiwa da binciken Intanet. Ma'anar waɗannan gajarce shine Mai Fassarar Adireshin Yanar Gizo, wato, "mai fassara adreshin hanyar sadarwa". Yana da, a kowane hali, muhimmin abu don samun damar yin amfani da hanyar sadarwar mu, fasaha ce wacce kusan dukkanin masu amfani da hanyar sadarwa na cikin gida da ƙwararrun ke haɗawa.
Kamar yadda sunanta ya nuna, babban aikin NAT shine daidai cewa: fassara adireshi don yin haɗin gwiwa. A cikin wannan rubutu za mu yi nazari ne kan abin da ya kunsa, tare da nuna muhimmancinsa, da karfi da rauninsa. A takaice, duk abin da kuke buƙatar sani game da NAT.
Duk da yake duk na'urorin da aka haɗa zuwa cibiyar sadarwa (wayoyi, kwamfutar hannu, kwamfutoci, da sauransu) suna da a adireshin IP na musamman, NAT ita ce ke da alhakin samar da adireshin IP na jama'a na haɗin gwiwa don wannan hanyar sadarwa. Ta wannan hanyar, maimakon sanya adireshin IP daban-daban ga kowane ɗayan na'urorin, NAT tana ba da adireshin guda ɗaya ga kowa (tsakanin 192.168.0.0 da 192.168.255.255). Babban fa'idar da wannan ya ƙunsa shine guje wa gajiyawar adireshin IPv4 da kuma ba da tabbacin haɗi mai kyau.
Adireshin IPv4 sun ƙunshi 32 bits, wanda ke ba da damar ƙirƙirar jimillar adireshi 4.294.967.296. Yana da alama adadi wanda ba za a iya samu ba, amma a gaskiya idan muka ninka adadin IPs a duniya ta yawan na'urorin da aka haɗa da kowannensu. Don haka muhimmancin aikin da NAT ta yi.
Yadda yake aiki
Aiki na NAT bidirectional ne. Wannan yana nufin cewa yana aiki duka don fassara adireshin IP mai zaman kansa da fassara shi zuwa adireshin IP na jama'a ko akasin haka. Yana iya zama kamar aiki mara nauyi, tunda babu wani cikas ga yin amfani da IP na jama'a kai tsaye. Duk da haka, mahimmancinsa yana cikin matsalolin da yake warwarewa. Waɗannan su ne mafi bayyanan misalai:
- Yana ba da mafita don matsalar da aka ambata a baya na gajiyawar IPV4.
- Yana rage tsadar samun IP na jama'a.
- Yana ba da damar dubban na'urori su haɗa zuwa intanit ta amfani da adireshin IP ɗaya na jama'a.
A yau kusan dukkanin hanyoyin sadarwa, na masu amfani da zaman kansu da na gwamnatocin jama'a da kamfanoni masu zaman kansu, suna yin ɗaya daga cikin NAT don haɗin gwiwar su. Kuma ana yin wannan don ƙarin dalili: da tsaro. Kuma shi ne, ban da ainihin aikin da aka yi cikinsa, NAT kuma tana aiki a matsayin nau'in tacewa wanda ke hana fakitin bayanai masu izini kawai da tabbatarwa daga shiga na'urorin mu masu zaman kansu.
Babu shakka, wannan baya bada garantin cikakkiyar kariya, kodayake yana samar da ƙarin sirri da tsaro wanda aka ba da shawarar sosai ga kowace hanyar sadarwa ta Intanet mai zaman kanta.
NAT iri
Akwai nau'ikan NAT iri-iri daban-daban, kodayake mafi mahimmancin su sun gangara zuwa uku masu zuwa:
a tsaye NAT
Adireshin sirri yana bayyana ta yadda koyaushe ana fassara shi zuwa adireshin jama'a iri ɗaya. Magani ne mai sauƙi kuma ana ba da shawarar a wasu lokuta (kamar don amfani a cikin na'urori waɗanda koyaushe suna da adireshin iri ɗaya don samun dama). A gefe guda, yana gabatar da wasu haɗari, tun da na'urarmu tana iya gani a kowane lokaci daga Intanet.
Dynamic NAT
Sai dai sabanin misalin da ya gabata. Anan NAT ba koyaushe yana zaɓar adireshin IP iri ɗaya ba, amma yana wasa tare da saitin adiresoshin IP na jama'a daban-daban. Duk lokacin da aka yi fassarar, za a sanya sabon adireshin IP.
PAT
Su ne gajarta Mai Fassarar Adireshin Port. Wannan tsarin yana ba da damar haɗin Intanet daga IP masu zaman kansu da yawa don haɗa su ta hanyar IP ɗaya na jama'a. Aikin da ake yi ta tashoshin jiragen ruwa. Babban fa'idarsa ita ce za mu iya ɓoye duk adiresoshin IP masu zaman kansu waɗanda muke da su akan hanyar sadarwar gida, wanda ke fassara zuwa ƙarin tsaro. Tabbas, akwai iyakance ga iyakar haɗin 216, wanda ya sa wannan zaɓin ba shi da amfani sosai a cikin manyan cibiyoyin sadarwa.
NAT: abũbuwan amfãni da rashin amfani
A taƙaice, za mu lissafta duk abubuwan da ke gaba da hakan dole ne mu tantance game da amfani da NAT a cikin haɗin gwiwarmu:
Pro
- ba mu damar adana adiresoshin IPv4, tunda ana iya haɗa na'urori da yawa zuwa Intanet tare da amfani da adireshin IP ɗaya na jama'a.
- Hanyar saitin kai tsaye kuma mai sauƙi.
- Es jituwa tare da kusan dukkanin ka'idojin sadarwa.
- Yana da wuya yana buƙatar kulawa.
- Yana nufin samar da haɗin gwiwarmu tare da a tsaro da, tunda ba a ganin na'urorin sadarwar mu daga waje.*.
- Es mafi m don haɗin rukuni.
(*) Sai dai a tsaye NAT, kamar yadda muka gani.
Contra
- yana buqatar a ƙara ƙarfin sarrafawa zuwa na'ura mai ba da hanya tsakanin hanyoyin sadarwa.
- Baya goyan bayan wasu ƙa'idodi, kamar ICM.
- Ragewa da Ƙarshen-zuwa-ƙarshen IP tracking.
- na iya haifar da wani lokaci sabani da wasannin kan layi, wanda ke buƙatar mafi kyawun bandwidth da latency.
- La matsala mai nisa ya fi rikitarwa.