I-Port 0 ayiyona inombolo yangempela yokudoba, kodwa kunenjongo yalo
Ngokungafani nezinombolo eziningi ze- port , i-port 0 iyi-port egcinwe ku-inthanethi ye- TCP / IP , okusho ukuthi akufanele isetshenziswe kumilayezo ye- TCP noma i- UDP .
I-Port 0 ithatha ukubaluleka okukhethekile ekuhlelweni kwenethiwekhi , ikakhulukazi uhlelo lwe-Unix socket, ngokucela uhlelo olunikezwa uhlelo, amathrekhi ashukumisayo. I-Port zero ifana nechweba le-wildcard elitshela uhlelo ukuthi lithole inombolo efanele ye-port.
Amathrekhi enethiwekhi ku-TCP no-UDP ububanzi kusukela enombolweni kuze kube ku-65535. Izinombolo zamaphandleni ebangeni eliphakathi kwe-zero no-1023 zichazwa njengezingxenyeni zesistimu noma amachweba aziwayo. I-Intanethi inikezele izinombolo zeziphathimandla (i-IANA) igcina uhlu olusemthethweni lwendlela okusetshenziselwa ngayo lezi zinombolo ze-port ku-intanethi, futhi i-port port 0 ayifanele isetshenziswe.
Yeka ukuthi i-Port 0 isebenza kanjani ku-Network Programming
Ukuhlela ukuxhumeka kwenethiwekhi entsha kudinga ukuthi inombolo eyodwa ye-port ihanjiswe kokubili komthombo nomthombo wokuphela. Imilayezo ye-TCP noma i-UDP ethunyelwe ngumsunguli (umthombo) iqukethe izinombolo zombili ze-port ukuze umamukeli womlayezo (okuya khona) akhiphe imilayezo yokuphendula emkhawulweni wokugcina weprotocol.
I-IANA inakekele ngaphambilini amarekhodi wesistimu aqokiwe ngezinhlelo zokusebenza ze-intanethi eziyisisekelo njengezinsizakalo zewebhu (port 80), kodwa izinhlelo eziningi zenethiwekhi ye-TCP no-UDP abanalo i-port yabo yesistimu futhi kumele zithole eyodwa kusuka ohlelweni lwazo lwamadivayisi njalo lapho ziqala ukusebenza.
Ukuze unikeze inombolo yayo ye-port source, izinhlelo zokusebenza zibiza imisebenzi yenethiwekhi ye-TCP / IP efana nokubopha () ukucela eyodwa. Uhlelo lokusebenza lungahlinzeka inombolo ehleliwe (ekhonjiwe kanzima) ukuze ibophe () uma ikhetha ukucela inombolo ethile, kodwa isicelo esinjalo singaphumeleka ngoba ezinye izinhlelo zokusebenza ezisebenzayo ohlelweni zingasebenzisa okwamanje.
Ngaphandle kwalokho, ingahlinzeka nge-port 0 ukuze ibophe () njengephameter yokuxhuma kwayo esikhundleni. Lokho kushukumisa uhlelo lokusebenza ukucinga ngokuzenzakalelayo futhi ubuyisele ichweba elifanele elikhona ku-TCP / IP ibanga lezinombolo ezibukhali.
Qaphela ukuthi uhlelo lokusebenza ngeke lunikezwe i-port 0 kodwa kunalokho elinye ichweba elinamandla. Inzuzo yalo mhlangano wokuhlela iyasebenza. Esikhundleni sesicelo ngasinye kufanele sisebenzise futhi sisebenzise ikhodi yokuzama amathrekhi amaningi aze athole eyodwa evumelekile, izinhlelo zokusebenza zingathembela ohlelweni lokusebenza ukwenza kanjalo.
I-Unix, iWindows, nezinye izinhlelo zokusebenza zihluka kancane ekuphatheni kwazo kwe-port 0, kodwa umhlangano jikelele ofanayo usebenza.
I-Port 0 ne-Network Security
Ithrekhi yenethiwekhi ethunyelwe kuwo wonke ama-intanethi wesimanje ukulalela ku-port 0 ingahle ikhiqizwe kubahlaseli benethiwekhi noma ngengozi ngezinhlelo zokusebenza ezihlelwe ngokungalungile. Imilayezo yokuphendula eyenziwa yi-Hosting ikhiphe impendulo ku-port 0 ithrafikhi ingasiza abahlaseli ukuthi bafunde kabanzi mayelana nokuziphatha nokukhubazeka kwenethiwekhi kulawo madivayisi.
Abahlinzeki abaningi be- intanethi (ISPs) bavimbela ithrafikhi ku-port 0 (kokubili imilayezo engenayo nephumayo) ukusiza ukuqapha lezi zinto.