Cryptographic txoj kev ntawm cov ntaub ntawv tiv thaiv: tswvyim, tus yam ntxwv, qhov tseem ceeb txaus

Dictionaries muab peb ze rau txhua lwm yam semantic ntsiab txhais ntawm lub sij hawm "cryptography", differing xwb nyob rau hauv cov cheeb tsam ntawm nws daim ntawv thov. Cryptography - qhov kev kawm ntawm yuav ua li cas los tiv thaiv ntaub ntawv los ntawm ib tug ntau yam ntawm txoj kev, yog tias tsim nyog, cov kev txwv nyob rau hauv cov powers mus xyuas nws thiab nws siv.

Cryptographic txoj kev ntawm cov ntaub ntawv tiv thaiv - yog lub transformation ntawm cov ntaub ntawv rau nws ntxiv kis tau tus mob mus rau lub tso cai tus neeg. Lub hauv paus ntsiab lus ntawm cov kev yog raws li nram no. Primary qhib encrypted lus, kis tau rau hauv daim ntawv ntawm kaw ntawv nyeem los yog graphics hu ua cryptogram. Ntxiv cryptogram yog kis tau ntau tshaj ib tug ruaj ntseg los yog insecure channel kis ntaub ntawv tau txais point. Ib tug tau kev tso cai cov neeg siv yog rov qab los yog seev suab ntawm tus tau txais cov lus thiab tau txais tus thawj plaintext. Yog li, lub interception Shirograms tsis tau tso cai neeg yuav tsis muaj peev xwm nyeem nws, tsis paub txog dab tsi zoo ntawm cryptographic ntaub ntawv tiv thaiv txoj kev siv rau encryption.

Lub tswvyim tseem ceeb cryptography yog feem ntau siv, uas tso cai rau kos ib thaum uas tig mus nyob nruab nrab ntawm lub encrypted ntaub ntawv, thiab coding system. Cryptographic tiv thaiv ntawm cov ntaub ntawv siv rau encrypting thiab decrypting ib tug tshwj xeeb ib theem zuj zus ntawm cov cim, uas yog hu ua tus tseem ceeb. Yog li, los ntawm kev siv lub tib lub cryptographic algorithm encryption tshwm sim nyob rau hauv lub qhov tseem ceeb.

Daws rau lawv faib faib mus rau hauv:

• symmetrical, piv txwv li lub sender thiab receiver nyob rau hauv tus txheej txheem ntawm encryption thiab decryption siv tib qhov tseem ceeb, uas saib kuas ib tug siab tsis pub tus encrypted lus, tab sis ib qho teeb meem nyob rau hauv lub hauj lwm ntawm lub lag luam nyob rau hauv txawv systems, qhov twg ib tug loj tus naj npawb ntawm cov neeg siv;
• asymmetric, nyob rau hauv qhov tseeb nws yog suav tias yog ib tug tseem ceeb khub, uas muab ib tug raug kaw (private) thiab pej xeem lag luam.

Lub hauv paus ntsiab lus ntawm lub ntsiab khub yog: lwm yam tseem ceeb yog siv los ua kom cov pej xeem tseem ceeb, tab sis muaj peev xwm tsis tsum generated rov qab mus rau lub npe hu pej xeem tseem ceeb. Qhov no kom hais tias lub authentication xyuas thaum Identify ntaub ntawv, kos npe los ntawm lub tshuab hluav taws xob cov kos npe (Eds).

Cryptographic ntaub ntawv tiv thaiv siv asymmetric tuav zoo rau encrypting kis es tsis txhob ntawm lub cia ntaub ntawv. Cov pej xeem hauv lub lag luam yog zoo tagnrho rau hloov li ib txwm kos npe rau ntawm lub tshuab hluav taws xob (digital), uas yog dav siv nyob rau hauv Internet kev them nyiaj systems.

Cryptographic txoj kev ntawm cov ntaub ntawv tiv thaiv yuav tsum tau raws li cov cai nram no:

1. Muaj ruaj khov cipher muaj peev xwm ntawm tiv cryptanalysis thiab muab ib txoj kev ntawm nws qhib xwb los exhaustive nrhiav lub lag luam. Yog li ntawd, qhov yuav tshwm txiav txim tseem ceeb nyob ntawm nws ntev.
2. Yuav ua kom durability ntawm ib tug cryptographic system los ntawm securely khaws cia tsis pub leejtwg paub lub lag luam thiab algorithms tsis siv lawv.
3. Yuav kom tsim qhov ntim ntawm coded cov ntaub ntawv uas tsis pub tshaj tus thawj.
4. Tshem tawm distortion thiab tsis ntawm cov ntaub ntawv vim tsis thaum encrypting.
5. Yuav ua kom yam tsawg kawg nkaus encoding lub sij hawm.
6. Muaj taub hau ntawm lub encryption nqi thiab tus nqi ntawm cov thawj ntaub ntawv.

Cryptographic txoj kev ntawm cov ntaub ntawv tiv thaiv yog yus muaj los ntawm kuj ntawm lub cipher, uas yog lub ntsiab ntawm kev ntsuas cov hauj lwm zoo. Qhov no ua hauj lwm zoo yog ib tug nqi nyob rau hauv lub sij hawm los yog tus nqi ntawm cov nyiaj uas yuav tsum tau muab lub qhov decryptor thawj lus nyob rau hauv qhov qhaj ntawv los ntawm lub encoded tseem ceeb. Muab muaj tsis muaj weaknesses nyob rau hauv encryption algorithms, uas sai sai laij cov craftsmen, thiab txhim khu kev qha txaus tseem ceeb ntev, cov nqi no loj hlob ho.