kashi na biyar cikin jerin kasidun da muke kawowa kan hanyoyin da yan dandatsa ke bi wajen aiwatar da ta’addancinsu ga kwamfutocin jama’a.
A sha karatu lafiya. Darasi Na (02): “Scanning Networks” Bayan darasi kan yadda ake tattaro bayanai kan kwamfuta ko kamfani ko wata na’urar da ake son isa gare ta. A darasi na biyu mai take: “Scanning Networks,” ana karantar da dalibai ne yadda zasu yi amfani da bayanan da suka samo daga wancan bincike, wajen isa ga wata kwamfuta ko na’ura ta musamman da suka samo adireshi ko sunanta. Kafin nan, zai dace mai karatu ya fahimci cewa, duk wata kwamfuta da kake iya isa gareta a tsarin sadarwa na zamani, tana ajiye ne a wani zangon sadarwa na musamman, dake wani wuri na musamman, a wata kasa ko jiha ko gari na musamman, cikin ginin wani kamfani ko ofishi ko gida ko daki na musamman. Wannan zango shi ake kira: “Local Area Network” (LAN), wanda munyi darasi kan shi a kasidarmu mai take: “Tsarin Sadarwa Tsakanin Kwamfutoci,” a shekarun baya. Wannan zango mai suna LAN a gajarce, yana dauke ne da kwamfutoci da aka hada alaka a tsakaninsu. Misali, hokumomin gwamnati da wasu kamfanoni masu zaman kansu suna da kwamfutoci da suke amfani dasu a ma’aikatansu. Wadannan kwamfutoci an hada su da juna ne, ta yadda za ka iya isa wata kwamfutar daga kwamfutar da kake aiki a kai, muddin an baka iznin yin hakan. Daga cikin wadannan kwamfutoci, duk kwamfutar dake jone da Intanet, a matsayin Uwar Garke (Web Server), idan aka gudanar da bincike mai kyau ana iya samun lambarta, wato: “IP Address”. Idan anyi sa’a ma har da sunanta (Host Name), da sunayen ma’aikatan dake hukumar (Username), da lambobin wasu kwamfutocin dake zangon baki daya. Wanda shi ne tsarin da darasin baya ke karantarwa. Da zarar ka iya samun wadannan bayanai, sai matakin tantance kwamfutocin ta hanyar bayanan da ka samu a matakin farko. Wannan shi ake kira: “Scanning Networks.” Manufa da Tsari Babbar manufar wannan mataki shi ne: “Tantance kwamfutoci da na’urorin sadarwar dake wani zango na sadarwa, don tabbatar da masu rai daga cikinsu, da abubuwan da suke dauke dasu.” A wannan mataki dai za a karantar da dalibi ne yadda zai kwankwasa kofar wani zangon sadarwa, don sanin wadanda ke cikin zangon, da bayanan da suke dauke dasu, don sanin hanyar da zai bi don daukowa ko nadewa ko saukar da duk abin da yake bukata. Hakan na yiwuwa ne ta hanyar shigar da lambar kwamfutar (IP Address, misali: 192.168.115.12) a kan wata manhaja ta musamman da aka tanada, don nemo bayanan da suka shafeta. Daga cikin bayanan kuwa akwai nau’in babbar manhaja (Operating System), da zubinta (Version), da kafofin sadarwar da kwamfutar ke dauke dasu, wato: “Ports” da manhajojin sadarwar dake dauke a kowace kafar sadarwa. Misali, a kafar sadarwa mai lamba ta: 25 ne ake samun manhajar sadarwar Imel, wato: “Simple Mail Transfer Protocol” (SMTP). A kafar sadarwa mai lamba ta 80 kuma ake samun manhajar ka’idar sadarwa ta Intanet, wadda da it ace kwamfuta ke iya sadar da keg a Intanet, wato: “Hypertext Transfer Protocol” (HTTP). Bayan haka, ta wannan hanya ne za a sanar da dalibi yadda zai gane ko wadancan kafafe na sadarwa a kunne suke ko a kashe suke. Sannan ta haka zai iya gane wasu manhajoji ne a kunne a kafar. Wadannan kananan manhajoji su ake kira: “Services.” Sannan idan kafafen a toshe suke, akwai yadda za ka iya gane dabarun da aka yi amfani dasu wajen toshe su. Sannan idan zangon sadarwa na dauke da wasu manhajojin tsaro da aka sa, irin su: “Intrusion Detection System” (IDS), ko “Intrusion Prevention Sysmte” (IPS), ko “Firewall” (Garkuwar wuta), duk za ka iya ganewa. A karshe kuma a koya maka yadda za ka iya waske wadannan hanyoyin tsaro cikin sauki. Nau’ukan Hanyoyin Tantancewa Tsarin haka alaka tsakanin kwamfutoci ya kasu kashi biyu ne: akwai tsari na kai tsaye wanda ke amfani da lambar IP. Wannan shi ake kira: “IP/TCP Connection.” Wannan tsarin ya fi aminci, wajen tabbatar da samuwar alaka tsakanin kwamfutoci wajen aika sakonni a tsakaninsu. Komai a bayyane yake. Tsari na biyu shi ake kira: “UDP Connection.” A wannan tsari, wanda yana amfani ne da tsarin wayar-iska (wato: “Connectionless system”), ba ka iya gane isar sakonni tsakanin kwamfutoci, sun isa ko basu isa ba? A tsarin farko, idan ka aika sako zuwa ga wata kwamfuta, idan a kashe take, nan take za a dawo maka da sakonka, kai tsaye. Amma a tsari na biyu, muddin sakon bai je ba, sai dai kaji shiru.
Comments
Post a Comment