Mokhoa oa ho Fumana Liphoso: Ho Boloka Botšepehi ba Lintlha Litsamaisong tsa Puisano
Pendahuluan
Ka kgolo e potlakileng ya theknoloji le puisano ya dijithale, bohlokwa ba ho boloka botsitso ba data bo ke ke ba feteletswa. Tsamaisong efe kapa efe ya puisano, ebang ke phetiso ya data ka marangrang a khomphutha, polokelo ya data ya dijithale, kapa phetiso ya matshwao mecheng ya puisano, ho netefatsa hore data e amohetsweng e tshwana hantle le data e rometsweng ho bohlokwa. Mekgwa ya ho lemoha diphoso ke motheo wa ho boloka botsitso bona ba data, e leng motheo wa botsitso le botshepehi ba mahlale a mangata ao re a sebedisang kajeno.
Bohlokoa ba ho Fumana Liphoso
Liphoso phetisong ea data li ka bakoa ke mabaka a fapaneng, ho kenyeletsoa tšitiso ea motlakase, tšitiso ea lets'oao, ho hloleha ha hardware, kapa liphoso mecheng ea phetiso. Liphoso tsena li ka fapana ho tloha ho li-bit tse khutlisitsoeng morao, tse sieo, kapa esita le tse ekelitsoeng. Ntle le mekhoa e nepahetseng ea ho lemoha liphoso tsena, data e fetisetsoang e ka senyeha 'me ea baka liphoso tse bolaeang lits'ebetsong tse itšetlehileng ka eona. Mohlala, phetiso ea lifaele, puisano ea seva ho seva, esita le ts'ebetso ea lichelete e ka beoa kotsing.
Mefuta ea Liphoso ho Lintlha
1. Phoso ea Bit e le 'Ngoe
Phoso ea biti e le 'ngoe e etsahala ha karolo e le 'ngoe ea data e fetoha ho tloha ho 0 ho ea ho 1 kapa ka tsela e fapaneng. Ena ke phoso e bonolo ka ho fetisisa ho e lemoha le ho e lokisa.
2. Liphoso tsa ho phatloha
Liphoso tsa ho phatloha li etsahala ha sehlopha sa li-bit tse latellanang ho data se fosahetse. Ho phatloha hona ho ka fapana ka bolelele 'me hangata ho thata ho ho lemoha le ho ho lokisa ho feta liphoso tsa bit e le 'ngoe.
3. Liphoso tse Pheta-phetoang
Phoso e iphetang ke mofuta oa phoso e hlahang khafetsa sebakeng se le seng sa bit libolokong tse ngata tsa data.
Mekhoa ea ho Fumana Liphoso
1. Tlhahlobo ea Parity
Mokhoa oa ho hlahloba parity ke mokhoa oa motheo oa ho lemoha liphoso tsa single-bit. Parity bit ke biti e eketsehileng e ekelitsoeng sete ea li-bit ho netefatsa hore palo ea li-1 sete e lekana (even parity) kapa e makatsa (odd parity). Ha data e amoheloa, sistimi e bala palo ea li-1 mme e netefatsa hore e lumellana le parity e lebelletsoeng. Haeba ho fumanoa phapang, ho bile le phoso.
Mohlala o bonolo: haeba re na le data 1101 mme re sebedisa tekanyo e lekanang, re eketsa karolo e eketsehileng e le hore data e fetiseditsweng e be 11011 (di-bit tse nne tse 1, palo e lekanang). Haeba data e amohetsweng e le 11001 (di-bit tse tharo tse 1, nomoro e sa tlwaelehang), phoso e a fumanwa.
2. Chekesum
Ho hlahloba liphoso ke mokhoa o rarahaneng haholoanyane oa ho lemoha liphoso o atisang ho sebelisoa liprothokholeng tsa marang-rang. Lintlha li arotsoe ka likarolo, 'me boleng bohle ba karolo ka 'ngoe (checksum) boa baloa. Checksum ena e romelloa le data. Moamoheli o bala checksum ea data e amohetsoeng ebe o e bapisa le checksum e amohetsoeng. Haeba ho na le phapang, phoso ea fumanoa.
Mokhoa ona o sebetsa hantle haholo ho fumaneng mefuta e fapaneng ea liphoso ho kenyeletsoa le liphoso tse phatlohileng.
3. Tlhahlobo ea ho Fokotsa Bofokoli ba Potoloho (CRC)
CRC ke e 'ngoe ea mekhoa e tsebahalang haholo ea ho lemoha liphoso phetisong ea data. Mokhoa ona o sebelisa algorithm e rarahaneng haholoanyane ea lipalo, moo data e bonoang e le polynomial ea binary ebe e aroloa ke polynomial ea jenereithara. Sephetho sa karohano ena ke masala, a tsejoang e le khoutu ea CRC.
Ha data e romelloa ka khoutu ea CRC, moamoheli o etsa karohano e tšoanang. Haeba karohano e sa fella ka masala, data e amoheloa ka nepo. Ho seng joalo, phoso e fumanoe.
4. Khoutu ea Hamming
Khoutu ea Hamming ke mokhoa o sebelisoang eseng feela ho lemoha empa hape le ho lokisa liphoso tsa bit e le 'ngoe. Ka ho eketsa bit ea parity sebakeng se itseng ka tatellano ea li-bit tsa data, moamoheli a ka fumana boemo bo nepahetseng ba bit e fosahetseng. Mohlala, khoutu ea 7,4 Hamming e fetola li-bit tse 4 tsa data hore e be li-bit tse 7 ka ho kopanya li-bit tse 3 tsa parity.
Haeba phoso e hlaha ho e 'ngoe ea li-bit, moamoheli a ka e lemoha le ho e lokisa kapele a sebelisa li-bit tsena tse sa hlokahaleng.
5. Khoutu ea Reed-Solomon
Khoutu ea Reed-Solomon ke mokhoa oa ho lemoha le ho lokisa liphoso o sebelisoang haholo-holo litsamaisong tsa puisano tsa dijithale tse hlokang mamello e phahameng ea liphoso. Mokhoa ona o emeloa ke tšebeliso ea polynomial holim'a li-bit tse ngata, e lumellang ho lemoha le ho lokisa liphoso tse telele tse phatlohang.
Papiso ea Mekhoa ea ho Fumana Liphoso
| Mokhoa | Melemo | Mathata |
|——–|————|————-|
| Tlhahlobo ea Parity | E bonolo, e potlakileng, le e bolokang mehloli. | E sebetsa hantle feela bakeng sa ho lemoha liphoso tsa bit e le 'ngoe. |
| Checksum | E matla ho feta ho lekana, e lemoha mefuta e mengata ea liphoso ho kenyeletsoa le ho phatloha. | E ke ke ea lokisa liphoso, e li lemoha feela. |
| CRC | E sebetsa hantle haholo ho fumaneng liphoso tsa single-bit le burst. | E hloka palo e rarahaneng ho feta checksum. |
| Khoutu ea Hamming | E ka lemoha le ho lokisa liphoso tsa bit e le 'ngoe. | Ho feta tekano ho hoholo ka lebaka la ho eketsoa ha bit ea parity. |
| Khoutu ea Reed-Solomon | E khona ho lemoha le ho lokisa liphoso tse ngata ka har'a boloko ba data. | E rarahane haholo 'me e hloka ho baloa ho eketsehileng. |
Tšebeliso Bophelong ba Letsatsi le Letsatsi
Mekhoa ea ho lemoha liphoso e sebelisoa likarolong tse fapaneng tsa bophelo ba letsatsi le letsatsi. Mohlala, puisanong ea selefounu, li-CRC li sebelisoa ho netefatsa hore matšoao a amoheloang ha a senyehe. Marang-rang a lik'homphieutha, lipakete tsa data tse rometsoeng li lekanngoa ho sebelisoa li-checksum le li-CRC ho netefatsa hore lia tšepahala. Esita le mecheng ea polokelo joalo ka li-CD le li-DVD, Likhoutu tsa Reed-Solomon li sebelisoa ho lokisa liphoso tse bakoang ke ho ngoatheha kapa tšenyo ea 'mele ea disc.
Qetello
Mekhoa ea ho lemoha liphoso ke karolo ea bohlokoa ea litsamaiso tsa puisano tsa sejoale-joale. Ho sebelisoa mekhoa e fapaneng, ho tloha ho liteko tse bonolo tsa ho lekana ho ea ho likhoutu tse rarahaneng tsa Reed-Solomon, botšepehi ba data bo ka netefatsoa ho sa tsotellehe litšitiso tsa phetiso le polokelo. Ho utloisisa le ho kenya tšebetsong mekhoa ena ka nepo ke mohato oa bohlokoa ho netefatseng hore litsamaiso tsa puisano tsa dijithale li lula li tšepahala ebile li sebetsa hantle, ho qoba mathata a ka hlahang ka lebaka la liphoso tsa data. Lefatšeng le itšetlehileng haholo ka theknoloji ea tlhahisoleseling, karolo ea mekhoa ea ho lemoha liphoso e ke ke ea nyenyefatsoa.
