nyuuzyou/kompy huggingface dataset:
part around the solar year

99
G
To address this, a variation on the original escapement was invented in 1670, in England. It was called the
anchor escapement, which was a lever-based device shaped like a ship's anchor. The motion of a pendulum
rocks this device so that it catches and then releases each tooth of the escape wheel, in turn allowing it to turn
a precise amount. Unlike the original form used in early pendulum clocks, the anchor escapement permitted
the pendulum to travel in a very small arc. Moreover, this invention allowed the use of a long pendulum which
could beat once a second and thus led to the development of a new floorstanding case design, which became
known as the grandfather clock.
H
Today, highly accurate timekeeping instruments set the beat for most electronic devices. Nearly all computers
contain a quartz-crystal clock to regulate their operation. Moreover, not only do time signals beamed down
from Global Positioning System satellites calibrate the functions of precision navigation equipment, they do so
as well for mobile phones, instant stock-trading systems and nationwide power-distribution grids.
So integral have these time-based technologies become to day-to-day existence that our dependency on them is
recognised only when they fail to work.
Questions 15-17 - Few words to say about this book

161
Matching feature (findings)
Tips: in the text , underline the names , dates, numbers, etc. from the questions or options ,
so that you can then then locate quickly.
Example : Here is part of a text about the development of fertilizers in the nineteenth
century. In this example the questions follow the order of the text.
Food production was greatly improved in the nineteenth century. One reason behind the development of
effective fertilizers. The German chemist Justus von liebig (1803-1873) added considerably to
knowledge of plant nutrition indentifying the crucial importance of nitrogen . and the France scientist
Jean Baptiste boussingault (1802- 1887) discovered that different kinds of fertilizers required different
amounts of nitrogen. However a business venture by Von Lieble failed: although the fertilizer he sold
was much less expensive than the guano it was intended to replace, crops were unable to absorb it
adequately . Von Liebia later develop a manufacturing process for making beef extract cubes, which
are still used in kitchens around the world.
In Britain , Jhan bennet laws (1814-1900) owned a farm where he experimented with crops and
manures: at first he tested the effects of various manures on potted plants and later worked on crops in
the field . in 1849 the patented a successful superphosphate which was the first artificial manure.
Laws made provision for the experimental farm to continue after his death and it exists to this day.
Few words to say about this book - bet 88

159
In Patan, the state’s ancient capital, the stepwell of Rani Ki Vav (Queen’s Stepwell) is perhaps the finest
current example. It was built by Queen Udayamati during the late 11th century, but became silted up following
a flood during the 13th century. But the Archaeological Survey of India began restoring it in the 1960s, and
today it’s in pristine condition. At 65 metres long, 20 metres wide and 27 metres deep, Rani Ki Vav features
500 distinct sculptures carved into niches throughout the monument, depicting gods such as Vishnu and
Parvati in various incarnations. Incredibly, in January 2001, this ancient structure survived
a devastating earthquake that measured 7.6 on the Richter scale.
Another example is the Surya Kund in Modhera, northern Gujarat, next to the Sun Temple, built by King
Bhima I in 1026 to honour the sun god Surya. It’s actually a tank (kund means reservoir or pond) rather than a
well, but displays the hallmarks of stepwell architecture, including four sides of steps that descend to the
bottom in a stunning geometrical formation. The terraces house 108 small, intricately carved shrines between
the sets of steps.
Rajasthan also has a wealth of wells. The ancient city of Bundi, 200 kilometres south of Jaipur, is reknowned
for its architecture, including its stepwells. One of the larger examples is Raniji Ki Baori, which was built by
the queen of the region, Nathavatji, in 1699. At 46 metres deep, 20 metres wide and 40 metres long,
the intricately carved monument is one of 21 baoris commissioned in the Bundi area by Nathavatji.
In the old ruined town of Abhaneri, about 95 kilometres east of Jaipur, is Chand Baori, one of India’s oldest
and deepest wells; aesthetically, it’s perhaps one of the most dramatic. Built in around 850 AD next to the
temple of Harshat Mata, the baori comprises hundreds of zigzagging steps that run along three of its sides,
steeply descending 11 storeys, resulting in a striking geometric pattern when seen from afar. On the fourth
side, covered verandas supported by ornate pillars overlook the steps.
Still in public use is Neemrana Ki Baori, located just off the Jaipur–Dehli highway. Constructed in around
1700, it’s nine storeys deep, with the last two levels underwater. At ground level, there are 86 colonnaded
openings from where the visitor descends 170 steps to the deepest water source.
Today, following years of neglect, many of these monuments to medieval engineering have been saved by the
Archaeological Survey of India, which has recognised the importance of preserving them as part of the
country’s rich history. Tourists flock to wells in far-flung corners of northwestern India to gaze in wonder at
these architectural marvels from 1,000 years ago, which serve as a reminder of both the ingenuity and artistry
of ancient civilisations and of the value of water to human existence
Variant – 7 - "Texnologik o’lchashlar va asboblar" fanidan oraliq nazorat yozma ish savollari

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"Texnologik o’lchashlar va asboblar" fanidan oraliq nazorat yozma ish savollari
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bet | 3/9 | Sana | 05.01.2024 | Hajmi | 104,5 Kb. | | #130769 |
Bog'liq 1-ONVariant – 7
Millivoltmetrning ishlash prinsipi.
To’liq nurlanish pirometrlarining tuzilishi va ishlash prinsipini tushintiring.
Namunaviy o‘lchash vositalari.
Qarshilik termometrlarini ulash usullari.
Temperatura. Temperaturani o‘lchash vositalari.
Tuzuvchi S.Eshqobilov
“5311000 - Texnologik jarayonlar va ishlab chiqarishni avtomatlashtirish va boshqarish
(neft, neft-kimyo va oziq-ovqat sanoati)” ta’lim yo’nalishlari uchun
“Nazoratning texnologik asboblari” fanidan oraliq nazorat yozma ish savollari
2018-2019 o’quv yili, I-semestr
Variant – 8
Temperaturani maxsus o‘lchash uchun termometrlar.
Termoelektrik o‘zgartirgichlar.
Temperatura o‘lchash vositalarining tasnifi.
Qarshilik termometrlari qanday metallardan yasaladi?
Manometrlarning ishlash prinsipi va ishlatilish sohasi.
Tuzuvchi S.Eshqobilov
“5311000 - Texnologik jarayonlar va ishlab chiqarishni avtomatlashtirish va boshqarish
(neft, neft-kimyo va oziq-ovqat sanoati)” ta’lim yo’nalishlari uchun
“Nazoratning texnologik asboblari” fanidan oraliq nazorat yozma ish savollari
2018-2019 o’quv yili, I-semestr
Variant – 9
Bosimning qanday turlarini bilasiz?
Sig‘imli manometrlar.
Suyuqlikli manometrik termometrlar.
Kvazimonoxromatik (optik) pirometrlar.
Qattiq jismlar sirtining temperaturasini o‘lchash.
Tuzuvchi S.Eshqobilov
“5311000 - Texnologik jarayonlar va ishlab chiqarishni avtomatlashtirish va boshqarish
(neft, neft-kimyo va oziq-ovqat sanoati)” ta’lim yo’nalishlari uchun
“Nazoratning texnologik asboblari” fanidan oraliq nazorat yozma ish savollari
2018-2019 o’quv yili, I-semestr
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Variant – 26 - "Texnologik o’lchashlar va asboblar" fanidan oraliq nazorat yozma ish savollari

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"Texnologik o’lchashlar va asboblar" fanidan oraliq nazorat yozma ish savollari
|
bet | 9/9 | Sana | 05.01.2024 | Hajmi | 104,5 Kb. | | #130769 |
Bog'liq 1-ONVariant – 26
O'lchov asbobi nima?
Mutloq va tasodifiy xatoliklar.
Qarshilikli manometrlar.
To‘liq nurlanish (radiatsion) pirometrlari.
Silfonli manometrlarning tuzilishi va ishlash prinsipini tushuntiring.
Tuzuvchi S.Eshqobilov
“5311000 - Texnologik jarayonlar va ishlab chiqarishni avtomatlashtirish va boshqarish
(neft, neft-kimyo va oziq-ovqat sanoati)” ta’lim yo’nalishlari uchun
“Nazoratning texnologik asboblari” fanidan oraliq nazorat yozma ish savollari
2018-2019 o’quv yili, I-semestr
Variant – 26
Sistematik, mutloq, subektiv va qupol xatoliklar.
Namunaviy o‘lchash vositalari.
Kvazimonoxromatik (optik) pirometrlar.
Bir naychali (kosali) bosim o‘lchash asboblarining ishlash prinsipi haqida tushuncha bering.
Muvozanatlashmagan ko‘prik sxema.
Tuzuvchi S.Eshqobilov
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Алгоритм - download

Qidiruv: Алгоритм
1. Алгоритм чанд шакл дорад? А ду шакл в чор шакл с панҷ шакл d се шакл Намудҳои алгоритм кадомҳоянд?
D забони барномасозие, ки барои ҳалли масъалаҳои гуногун, системаҳои тафаккури сунъи пешбини шудааст
22,95 Kb.
1
o'qib
Алгоритм Крускала
Самостоятельная работа
268,77 Kb.
1
o'qib
Ózbekstan respublikasí informaciyalíq texnologiyalarí HÁm kommunikaciyalarín rawajlandíRÍw ministrligi
«Telekommunikaciya texnlogiyaları» tálim baǵdarı 30003-20 sırtqı 3- basqısh studenti Jumabaeva Kamilanin’ «Маглуматлар дуилиси хам Алгоритм» páninen
130,08 Kb.
3
o'qib
1
Bosh sahifa
Aloqalar
Bosh sahifa
Dərs
Mühazirə
Qaydalar
Referat
Xülasə
Yazı
Bajardi: Mahmudov Shamsxon

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Bajardi: Mahmudov Shamsxon
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bet | 1/4 | Sana | 15.12.2023 | Hajmi | 2,37 Mb. | | #119840 |
Bog'liq kiber.muslaqil ish №1 Toshkent Axborot Texnologiyalari Universiteti
KIBERXAFSIZLIK ASOSLARI
Bajardi: Mahmudov Shamsxon
Reja: - Identifikatsiya
- Aytentifikatsiya
- Avtarizatsiya
- Parollar
- Xulosa
Mavzu: Identifikatsiya va autentifikatsiya tushunchasi va vazifalari
Identifikatsiya va autentifikatsiya tushunchasi va vazifalari. - Tizim resulslarini boshqarish bilan bog`liq bolgan ixtiyoriy xafsizlik muammosi uchun biz ruxsatlarni nazoratlash terminini “soyabon” sifatida foydalansak bo`ladi.
- Ruxsatlarni nazotarlash sohasi quyidagi qism sohalardan iborat.
- Identifikatsiya
- Autentifikatsiya
- Abtorizatsiya
Identifikatsiya - Identifikatsiya (Identification) - foydalanuvchini uning identifikatori (nomi) bo’yicha aniqlash jarayoni. Bu foydalanuvchi tarmoqdan foydalanishga uringanida birinchi galda bajariladigan funktsiyadir. Foydalanuvchi tizimga uning so’rovi bo’yicha o’zining identifikatorini bildiradi, tizim esa o’zining ma’lumotlar bazasida uning borligini tekshiradi.
Autentifikatsiya - Autentifikatsiya (Authentication) — ma’lum qilingan foydalanuvchi, jarayon yoki qurilmaning haqiqiy ekanligini tekshirish muolajasi. Bu tekshirish foydalanuvchi (jarayon yoki qurilma) haqiqatan aynan o’zi ekanligiga ishonch xosil qilishiga imkon beradi. Autentifikatsiya o’tqazishda tekshiruvchi taraf tekshiriluvchi tarafning xaqiqiy ekanligiga ishonch hosil qilishi bilan bir qatorda tekshiriluvchi taraf ham axborot almashinuv jarayonida faol qatnashadi. Odatda foydalanuvchi tizimga o’z xususidagi noyob, boshqalarga ma’lum bo’lmagan axborotni (masalan, parol yoki sertifikat) kiritishi orqali identifikatsiyani tasdiqlaydi.
Identifikatsiya va autentifikatsiya sub’ektlarning (foydalanuvchilarning) haqiqiy ekanligini aniqlash va tekshirishning o’zaro bog’langan jarayonidir. Muayyan foydalanuvchi yoki jarayonning tizim resurslaridan foydalanishiga tizimning ruxsati aynan shularga bog’liq. Sub’ektni identifikatsiyalash va autentifikatsiyalashdan so’ng uni avtorizatsiyalash boshlanadi - Identifikatsiya va autentifikatsiya sub’ektlarning (foydalanuvchilarning) haqiqiy ekanligini aniqlash va tekshirishning o’zaro bog’langan jarayonidir. Muayyan foydalanuvchi yoki jarayonning tizim resurslaridan foydalanishiga tizimning ruxsati aynan shularga bog’liq. Sub’ektni identifikatsiyalash va autentifikatsiyalashdan so’ng uni avtorizatsiyalash boshlanadi
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Foydalanilgan adabiyotlar

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Foydalanilgan adabiyotlar
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bet | 4/4 | Sana | 24.05.2024 | Hajmi | 60,64 Kb. | | #252852 |
Bog'liq mashinali ok1Foydalanilgan adabiyotlar
А.В. Гаврилов. Системы искусственного интеллекта: Учеб. пособие: в 2-х ч. - Новосибирск: Изд-во НГТУ, 2001. - Ч. 1. - 67 с.
Потапов А.С. Технологии искусственного интеллекта – СПб: СПбГУ ИТМО, 2010. – 218 с.
"Introduction to Machine Learning" by Alpaydin, Ethem
"Pattern Recognition and Machine Learning" by Bishop, Christopher M.
"Data Mining: Concepts and Techniques" by Han, Jiawei, Kamber, Micheline, and Pei, Jian
"Machine Learning: A Probabilistic Perspective" by Murphy, Kevin P.
"Neural Networks and Deep Learning: A Textbook" by Nielsen, Michael A.
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it was climbing that he spent his time on as a young man

TEST
TIM:
Hi, Laura – could you spare a few minutes to talk about the work placement you did last
summer? I’m thinking of doing one myself …
LAURA:
Hi, Tim. Sure.
TIM:
Didn’t you do yours at an environmental services company?
LAURA:
That’s right … It’s only a very small company and they needed someone to produce a
company brochure, and I wanted to get some business experience because I’m interested
in a career in occupational psychology in a business environment. It was good because I
had overall responsibility for the project.
TIM:
What kind of skills do you think you developed on the placement? I mean, apart from the
ones you already had … Did you have to do all the artwork for the brochure, the layout and
everything?
LAURA:
We hired the services of a professional photographer for that. I did have to use my IT skills
to a certain extent because I cut and pasted text from marketing leaflets, but that didn’t
involve anything I hadn’t done before.
TIM:
And I don’t think using the phone meant I got less rich data rather

TEST
VICTOR:
Right, well, for our presentation shall I start with the early life of Thor Heyerdahl?
OLIVIA:
Sure. Why don’t you begin with describing the type of boy he was, especially
his passion
for collecting things.
Q21
/
Q22
VICTOR:
That’s right, he had his own the little museum. And I think it’s unusual for children to develop
their own values and not join in their parents’ hobbies; I’m thinking of how Heyerdahl wouldn’t
go hunting with his dad, for example.
OLIVIA:
Yeah, he preferred to learn about nature by listening to his mother read to him. And quite
early on he knew he wanted to become an explorer when he grew up. That came from his
camping trips he went on in Norway I think …
VICTOR:
No,
others have been dismantled in different parts of the region

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others have been dismantled in different parts of the region Pdf ko'rish
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bet | 196/209 | Sana | 22.11.2023 | Hajmi | 1,11 Mb. | | #103463 |
Bog'liq Listening transcripts 230531 122425others have been dismantled in different parts of the region
and rebuilt on the site. This hadn’t been attempted before in these parts
Q11
/
Q12
so we’re very
proud of what we have here. All the buildings are filled with furniture, machinery and objects. You may be
able to see these in other museums but not in their original settings.
What also sets Brampton apart
from other museums is that the story of the exhibits is told not by labels but by costumed staff
like myself.
Q11
/
Q12
I look after sheep, cows and hens, which are much the same as those you see on
modern farms, but I use traditional methods to care for them. You will also be able to see a blacksmith
and a printer, as well as other craftspeople. If you talk to them, you’ll be able to find out what life was
really like 150 years ago. Our programme of activities during the year has guided walks, an agricultural
fair and all the other events you would expect a museum to have, but remember: here you experience
them in the real surroundings.
The site is divided into different areas. The main building contains our High Street which is a street of
19th-century shops, offices and some homes. There’s a stationer’s shop which sells a range of specially
selected cards, prints and copies of Victorian stationery, all available for purchase by visitors. Upstairs
in the same building, a printer demonstrates the production of posters, business cards and advertising
material. Across the street from the stationer’s is a clothes shop and there’s a baker’s where you can
watch a demonstration of someone making bread, cakes and pastries. We also have a sweet shop which
has old–fashioned sweets for sale.
Vintage trams travel along from one end of the street to the other,
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Do you think you got any better at managing your time and prioritizing things? You

TEST
Guide: Welcome to Brampton Museum. I’m going to tell you a little bit about the museum first and then
show you around. As you can see, Brampton is an open–air museum. The
first open-air museums were
established in Scandinavia towards the end of the 19th century, and the concept soon spread throughout
Europe and North America and
there are several in Britain, all of which tell the history of a particular part
of the country.
Brampton focuses on life during the 19th century. The site was chosen because there were already some
historic 19th-century
buildings here and
Antivirus dasturiy - Vazirligi muhammad al-xorazmiy nomidagi toshkent

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Vazirligi muhammad al-xorazmiy nomidagi toshkent
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bet | 95/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
Antivirus dasturiy vositalarining kamchiligi. Antivirus dasturiy vositasiga kompyuterni himoyalashda amalga oshirilish lozim bo‘lgan zaruriy shart sifatida qaraladi. Umuman olganda, antivirus kompyuter uchun zararli dasturlarni skanerlashni, himoyalashni, karantin holatiga tushirishni va boshqa amallarni bajaradi. Antivirus dasturiy vositalarini CD-disklardan va Internet tarmog‘idan foydalangan holda o‘rnatish mumkin. Antivirus dasturiy vositalari bir biridan ko‘plab o‘ziga xos xususiyatlari bilan ajralib turadi. Masalan, Internet tarmog‘idan foydalanilganda reklamalarni blokirovkalash, Internet tarmog‘idan kirib keluvchi zararli dasturlarni blokirovkalash va h. Biroq, foydalanuvchilar to‘liq antivirus dasturiy vositalarining imkoniyatilariga ishonib qolmasliklari lozim.
Viruslarni doimiy aniqlash uchun antivirus dasturiy vositalari eng yangi va yangilangan ma’lumotlarni o‘z ichiga olgan namunaviy fayllarga muxtoj. Biroq, antivirus ishlab chiqaruvchilari yangi virus uchun namunaviy fayllar yaratgunlaricha virus ishlab chiqaruvchilari tomonidan katta hajmdagi yangi viruslar yaratiladi. Bu esa, yangi virus uchun vaksinani tayyorlash yetarlicha ko‘p vaqtni talab qiladi.
Bundan tashqari, antivirus dasturi Rootkit tipidagi zararli dasturlarni aniqlashda foydasi tegmasligi mumkin. Rootkit tipidagi zararli dasturlar kompyuter operatsion tizimining markaziga hujum qilishni maqsad qiladi.
Antivirus dasturiy vositalari sifatini baholash omillari. Antivirus dasturiy vositalari quyidagi omillarga ko‘ra baholanishi mumkin:
ishonchlik va foydalanishdagi qulaylik – antivirus dasturiy vositasini “qotib qolishi” va foydalanish uchun turli tayyorganlikni talab etmasligi;
barcha keng tarqalgan viruslarni sifatli aniqlash, hujjat fayllari/ jadvallari (MS Word, Excel), paketlangan, arxivlangan fayllarni skanerlash va zararlangan obyektlarni davolash qobiliyati;
barcha mashhur platformalar uchun mavjudligi (DOS, Windows NT, Novell NetWare, OS/2, Alpha, Linux va boshq), talab bo‘yicha va tezkor skanerlash rejimlarining mavjudligi;
ishlash tezligi va boshqa xususiyatlari.
Antivirus dasturiy komplekslari. Har bir antivirus dasturiy vositalar o‘ziga xos afzallik va kamchiliklarga ega. Faqat bir necha antivirus dasturiy vositalaridan kompleks foydalanish to‘liq himoyani ta’minlashi mumkin. Amalda ko‘plab antivirus dasturiy vositalar mavjud, ularga quyidagilarni misol sifatida keltirish mumkin (7.3-jadval).
7.3-jadval
Turli antivirus dasturlarining xususiyatlari
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Ochiq kalitli - Vazirligi muhammad al-xorazmiy nomidagi toshkent

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Vazirligi muhammad al-xorazmiy nomidagi toshkent
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bet | 33/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
Ochiq kalitli kriptotizimlarda kalit uzunligi. Simmetrik kalitli kriptotizimlarda bo‘lgani kabi ochiq kalitli kriptotizimlarda ham real hayotda foydalanish uchun kalit uzunligiga talablar qo‘yiladi. Yuqorida simmetrik kriptotizimlar uchun ushbu masala bilan tanishib o‘tilgan edi. Simmetrik va ochiq kalitli kriptotizimlarning matematik asosi turlicha bo‘lgani bois, ular bir xil bardoshlik darajasida bo‘lganida turli kalit uzunliklariga ega bo‘ladilar (3.4-jadval).
3.4-jadval Bir xil bardoshlikka ega simmetrik va ochiq kalitli kriptotizimlar
kalitlarining uzunligi
Simmetrik shifrlash algoritmi
|
RSA algoritmi (𝑝 𝑣𝑎 𝒒𝒒 𝑠𝑜𝑛𝑙𝑎𝑟𝒔𝒔)
|
56 bit
|
512 bit
|
80 bit
|
1024 bit
|
112 bit
|
2048 bit
|
128 bit
|
3072 bit
|
192 bit
|
7680 bit
|
256 bit
|
15360 bit
|
Simmetrik kriptotizimlarda bo‘lgani kabi ochiq kalitli kriptotizimlarda ham kalitlarni barcha variantlarini hisoblash qurilmalar imkoniyatiga bog‘liq. Ya’ni, hozirgi kunda yetarli deb qaralgan kalit uzunligi, 10 yildan keyin tavsiya etilmasligi mumkin. Chunki, 10 yil davomida hisoblash qurilmalarining imkoniyatlari hozirgi kundagi kabi bo‘lmaydi.
3.5-jadvalda RSA algoritmidagi 𝑁 modulning turli uzunligida faktorlash uchun talab etilgan vaqt qiymatlari ko‘rsatilgan. Bunda natijalar bir sekundda million amal bajaruvchi (one-million-instruction- per-second, mips) kompyuter yoki yiliga 1013 amal bajarilishi hisobida olingan. Faktorlash algoritmi sifatida GNFS (general number field sieve) dan foydalanilgan.
3.5-jadval RSA algoritmidagi 𝑁 modulning turli uzunligida faktorlash uchun
talab etiladigan vaqt qiymatlari
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QISQARTMA SO‘ZLAR RO‘YXATI

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QISQARTMA SO‘ZLAR RO‘YXATI
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bet | 98/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
QISQARTMA SO‘ZLAR RO‘YXATI
ABAC - Attribute-based access control AES - Advanced Encryption Standard APT - Advanced persistent threats
ASSII – American Standard Code for Information Interchange
AT – Axborot texnologiyalari CBC - Cipher Block Chaining CCTV - Closed-circuit television
CDMA - Code Division Multiple Access
CSEC2017 JTF – Cybersecurity Curricula 2017 Joint Task Force
CVE - Common Vulnerabilities and Exposures
DAC - Discretionary access control DES - Data Encryption Standard DLP - Data Leakage Prevention, DoD – Department of Defense DOS - Denial of service
ECB - Electronic codebook mode FAR - False Acceptance Rate FRR - False Rejection Rate
FTP – File Transfer Protocol
GNFS - General Number Field Sieve
GSM – Global System for Mobile Communications HMAC – hash-based message authentication code HTTP - Hypertext Transfer Protocol
HTTPS - Hypertext Transfer Protocol Secure
IDS - Instrusion Detection System IPS - Intrusion Prevention System IPSec - IP Security
ISO – International Organization for Standardization
IV - Initialization Vector
KDC - Key Destribution Center L2TP - Layer 2 Tunneling Protocol LAN - Local Area Network
MAC - Mandatory access control MAC - Message Authentication Code MAN - Metropolitan Area Network MITM - Man in the middle attack NAT - Network Address Translation
OWASP - Open Web Application Security Project
PAN - Personal Area Network
PIN - Personal Identification Number
PKI - Public key infrastructure
PPP – Point-to-Point Protocol
PPTP - Point-to-Point Tunneling Protocol RAID - Redundant Array of Independent Disks RBAC - Role-based access control
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Internet manbalari - Vazirligi muhammad al-xorazmiy nomidagi toshkent

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Vazirligi muhammad al-xorazmiy nomidagi toshkent
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bet | 97/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
ACR39U smart card rader [sayt]: http://smartkardtechnologies.com/productdetails/acr39u-smart-card- rader (murojaat vaqti: 29.10.2020).
Certified Network Defender [sayt]: https://iclass.eccouncil.org/our-courses/certified-network-defender-cnd/ (murojaat vaqti: 29.10.2020).
3D Airport Security X-ray Machine [sayt]: https://www.turbosquid.com/3d-models/3d-airport-x-ray-machine- security-1405223 (murojaat vaqti: 29.10.2020).
Web Applications vulnerabilities and threats: statistics for 2019 [sayt]: https://www.ptsecurity.com/ww-en/analytics/web- vulnerabilities-2020/ (murojaat vaqti: 29.10.2020).
How to Spot Phishing Emails [sayt]: https://www.nuigalway.ie/itsecurity/howtospotphishingemails/ (murojaat vaqti: 29.10.2020).
Beware of fake microsoft security essentials [sayt]: https://techjaws.com/beware-of-fake-microsoft-security-essentials/ (murojaat vaqti: 29.10.2020).
The Best Antivirus Protection for 2020 [sayt]: https://www.pcmag.com/roundup/256703/the-best-antivirus-protection (murojaat vaqti: 29.10.2020).
Securing Wireless Networks [sayt]: https://www.us- cert.gov/ncas/tips/ST05-003 (murojaat vaqti: 29.10.2020).
Why High Availability Is Important for Your Business [sayt]: https://blog.layershift.com/why-high-availability-for-your-business/ (murojaat vaqti: 29.10.2020).
Rutoken [sayt]: https://www.rutoken.ru/ (murojaat vaqti: 29.10.2020).
Comparison of disk encryption software [sayt]: https://en.wikipedia.org/wiki/Comparison_of_disk_encryption_software (murojaat vaqti: 29.10.2020).
G20 summit: NSA targeted Russian president Medvedev in London [sayt]: https://www.theguardian.com/world/2013/jun/16/nsa- dmitry-medvedev-g20-summit (murojaat vaqti: 29.10.2020).
CRADC Data Destruction and Return of Restricted Data Policy [sayt]: https://ciser.cornell.edu/wp- content/uploads/2017/01/CRADC_Destruction_and_Return_of_Restrict ed_Data.pdf (murojaat vaqti: 29.10.2020).
Privacy Impact Assessment Integrated Automated Fingerprint Identification System National Security Enhancements [sayt]: https://www.fbi.gov/services/information-management/foipa/privacy- impact-assessments/iafis (murojaat vaqti: 29.10.2020).
Best Keylogger for Windows 10 in 2020 [sayt]: https://www.pctattletale.com/blog/1505/best-keylogger-software- windows-10 (murojaat vaqti: 29.10.2020).
Windows Event Logging and Forwarding [sayt]: https://www.cyber.gov.au/acsc/view-all-content/publications/windows- event-logging-and-forwarding (murojaat vaqti: 29.10.2020).
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Ochiq kalitli - Vazirligi muhammad al-xorazmiy nomidagi toshkent

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Vazirligi muhammad al-xorazmiy nomidagi toshkent
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bet | 32/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
Ochiq kalitli kriptotizimlardan foydalanish. Ochiq kalitli kriptografik tizimlardan foydalanish masalasini ko‘rib chiqishda quyidagi belgilashlar kiritiladi:
𝐴 tomonning ochiq kaliti bilan xabar 𝑀 ni shifrlash: 𝐶 = {𝑀}𝐴.
𝐴 tomonning shaxsiy kaliti bilan shifrmatnni rasshifrovkalash:
𝑀 = [𝐶]𝐴.
Bundan quyidagi tenglikni osongina yozish mumkin: [{𝑀}𝐴]𝐴 = 𝑀. Boshqacha aytganda, 𝑀 xabarni 𝐴 tomonning ochiq kaliti bilan shifrlab, keyin aynan shu tomonning shaxsiy kaliti bilan rasshifrovkalash amalga oshirilsa, yana dastlabki xabar hosil bo‘ladi.
Simmetrik shifrlar bilan bajarilgan ixtiyoriy amalni, ochiq kalitli shifrlash algoritmlari bilan ham amalga oshirish mumkin. Masalan, tarmoqda ma’lumotlarni uzatishda va xavfsiz bo‘lmagan muhitda axborot konfidensialligini ta’minlashda simmetrik shifrlash algoritmlarining o‘rniga ochiq kalitli kriptografik tizimlardan foydalanish mumkin. Biroq, jarayon ko‘proq vaqt talab etadi.
Bundan tashqari, simmetrik kriptotizimlar kabi ochiq kalitli kriptotizimlardan ham ma’lumotlarning yaxlitligini ta’minlashda foydalanish mumkin.
Ochiq kalitli kriptotizimlar simmetrik kriptotizimlarda mavjud kalitni taqsimlash muammosini o‘zida bartaraf etgan. O‘z o‘rnida simmetrik kriptotizimlar ochiq kalitli kriptotizimlarga qaraganda samaradorligi bilan ajralib turadi. Boshqacha aytganda, shifrlash va rasshifrovkalash amallari simmetrik kriptotizimlarda, ochiq kalitli shifrlash algoritmlariga nisbatan, tezroq amalga oshiriladi.
Har ikkala kriptotizimning afzalliklarini birlashtirish imkoniyati mavjudmi? Ya’ni, ma’lumotni shifrlashda yuqori samaradorlikka ega va kalitlarni taqsimlash muammosi bo‘lmagan kriptotizimni yaratish mumkinmi? Albatta, buning imkoniyati mavjud va bunday tizimlar gibrid kriptotizimlar deb ataladi. Gibrid kriptotizimlarda simmetrik shifrlash algoritmining kaliti ochiq kalitni shifrlash orqali yetkazilsa, ma’lumotlarning o‘zi esa simmetrik shifrlash orqali himoyalanadi. Gibrid kriptotizim sxemasi 3.7-rasmda aks ettirilgan.
{K}B
E(B tomon ma’lumoti, K) E(A tomon ma’lumoti, K)
А tomon B tomon
3.7-rasm. Gibrid kriptotizim
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RSA algoritmi - Vazirligi muhammad al-xorazmiy nomidagi toshkent

RSA algoritmi. RSA nomi algoritmni yaratuvchilari familiyalarining birinchi harflaridan olingan (Rivest, Shamir va Adleman). RSA algoritmi modul arifmetikasining darajaga ko‘tarish amalidan foydalanishga asoslangan.
RSA algoritmida ochiq va shaxsiy kalitlar juftini generatsiyalash uchun ikkita katta uzunlikdagi 𝑝 va 𝑞 sonlari tanlanadi va ularning ko‘paytmasi hisoblanadi: 𝑁 = 𝑝 ∗ 𝑞. Shundan so‘ng 𝜑(𝑁) = (𝑝 − 1) ∗ (𝑞 − 1) bilan o‘zaro tub bo‘lgan, 𝑒 soni tanlanadi (𝜑(𝑁) funksiya ma’nosi quyida keltirilgan). Shundan so‘ng 𝜑(𝑁) modulda 𝑒 sonining teskarisi hisoblanadi va u 𝑑 ga teng bo‘ladi. Shundan so‘ng, ikkita tub sonning (𝑝 𝑣𝑎 𝑞) ko‘paytmasi 𝑁 va 𝑒𝑑 = 1 𝑚𝑜𝑑 𝜑(𝑁) shartni qanoatlantiruvchi 𝑒 va 𝑑 sonlari mavjud. Shundan so‘ng, 𝑝 𝑣𝑎 𝑞 lar esdan chiqariladi (o‘chirib tashlanadi).
Bu yerda, 𝑁 modul hisoblanib, (𝑁, 𝑒) ochiq kalit juftini va 𝑑 maxfiy kalitni tashkil etadi. RSA algoritmida shifrlash va rasshifrovkalash modul bo‘yicha darajaga oshirish asosida bajariladi. RSA algoritmida shifrlash uchun 𝑀 xabarni son ko‘rinishida ifodalash talab etiladi va 𝑁 modul bo‘yicha 𝑒 darajaga ko‘tariladi, ya’ni
𝐶 = 𝑀𝑒 𝑚𝑜𝑑 𝑁.
𝐶 ni rasshifrovkalash uchun uni 𝑁 modul bo‘yicha shaxsiy kalit 𝑑
darajaga ko‘tarish talab etiladi:
𝑀 = 𝐶𝑑 𝑚𝑜𝑑 𝑁.
Boshqacha aytganda, RSA algoritmida xabar ochiq kalit bilan shifrlansa va shaxsiy kalit bilan rasshifrovkalansa, 𝑀 = 𝐶𝑑 𝑚𝑜𝑑 𝑁 =
𝑀𝑒𝑑 𝑚𝑜𝑑 𝑁 tenglikning to‘g‘riligini isbotlash zarur.
Aytaylik, RSA algoritmida ma’lumotni shifrlash va rasshifrovkalash amallarini tanlab olingan (𝑝 = 11 𝑣𝑎 𝑞 = 3) “katta” sonlar ustida amalga oshirish talab qilinsin. Mazkur holda modul
𝑁 = 𝑝 ∗ 𝑞 = 33 ga teng bo‘ladi va 𝜑(𝑁) = (𝑝 − 1)(𝑞 − 1) = 20 ga
teng bo‘ladi. U holda shifrlash uchun zarur bo‘lgan daraja e ni (3) ga teng deb olish mumkin. Sababi, 3 soni 𝜑(𝑁) = 20 bilan o‘zaro tubdir. Shundan so‘ng, Evklidning kengaytirilgan algoritmi asosida rasshifrovkalash kaliti 𝑑 = 7 aniqlanadi. Ya’ni, 𝑒𝑑 = 3 ∗ 7 = 1 𝑚𝑜𝑑 20. U holda A tomonning ochiq kalit jufti 𝑁, 𝑒 = 33, 3 va shaxsiy kaliti 𝑑 esa 7 ga teng bo‘ladi.
Shundan so‘ng, A tomon o‘zining ochiq kalitini barchaga uzatadi.
Biroq, shaxsiy kalitini maxfiy saqlaydi.
Faraz qilaylik, B tomon A tomonga 𝑀 = 15 ma’lumotni shifrlab yubormoqchi. Buning uchun B tomon A tomonning ochiq kaliti juftini
𝑁, 𝑒 = 33,3 oladi va shifrmatnni quyidagicha hisoblaydi:
𝐶 = 𝑀𝑒 𝑚𝑜𝑑 𝑁 = 153 = 3375 = 9 𝑚𝑜𝑑 33
va uni A tomonga yuboradi.
A tomon 𝐶 = 9 shifrmatnni rasshifrovkalash uchun shaxsiy kalit
𝑑 = 7 dan foydalanadi:
𝑀 = 𝐶𝑑 𝑚𝑜𝑑 𝑁 = 97 = 4782969 = 144938 ∗ 33 + 15 = 15 𝑚𝑜𝑑 33
Agar RSA algoritmida kichik tub sonlardan (𝑝 𝑣𝑎 𝑞 𝑢𝑐ℎ𝑢𝑛) foydalanilgan taqdirda, hujumchi ochik bo‘lgan 𝑁 ni osonlik bilan ikkita tub sonning ko‘paytmasi ko‘rinishida yozishi mumkin. Shundan so‘ng, ochiq kalitning ikkinchi qism 𝑒 dan foydalangan holda, shaxsiy kalit 𝑑 ni hisoblay oladi. Shuning uchun RSA algoritmidan amalda foydalanish uchun tanlanuvchi tub sonlar uzunligi kamida 2048 bit bo‘lishi talab etiladi. Bundan tashqari, RSA algoritmini buzish faqat faktorlash muammosiga bog‘liqligi isbotlanmagan.
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-topshiriq - Gayubova komila anvarovna yulanova nargiza davlatovna akademik yozuv

2-topshiriq.
Venn diagrammasidan foydalanib, reja turlarini solishtiring.
3-topshiriq.
“Tushunchalar asosida matn tuzish” metodi bo‘yicha matn tuzish
“O‘rta Osiyoning buyuk siymolari” mavzusi bo‘yicha quyida berilgan tayanch
so‘z va birikmalardan foydalanib mustaqil tarzda mikromatnlar tuzing.
1) Xorazm, Bog’dod akademiyasi, rasadxona, o‘nlik tizim, to‘rt amal,
algoritm, algebra;
2) Samarqand, sakkizta asar, «Samoviy jismlarning harakati va yulduzlar
ilmi», astronomiyadan qo‘llanma;
3) Forob, Damashq, Misr, 160 dan ortiq asar;
4) Kat shahri, Ma’mun akademiyasi, xorijiy tillar, 200 ga yaqin ilmiy asar,
globus, «Qadimgi xalqlardan qolgan yodgorliklar», «Hindiston», G’azna;
5) Sayram, Yassi, 23 yosh, «Hikmatlar».
68
4- topshiriq
.
Nima uchun barglar kuzda rangni o‘zgartiradi?
Barglar yashil rangda paydo bo‘lganda, ular xlorofilning ko‘pligi bilan
bog’liq. Faol bargda juda ko‘p xlorofil bor, bu yashil niqoblar boshqa pigment
ranglariga ega. Nur xlorofil ishlab chiqarishni tartibga soladi, shuning uchun kuz
kunlari kun sayin kamayib boradi, kamroq xlorofil ishlab chiqariladi. Xlorofilning
parchalanish tezligi barqaror bo‘lib qoladi, shuning uchun yashil rang barglardan
pasayadi. Shu bilan birga, shakar konsentratsiyasining kuchayishi antosiyanin
pigmentlarini ishlab chiqarishning oshishiga olib keladi. Avvalo antosiyaninlarni
o‘z ichiga olgan yaproqlar qizil rangga ega bo‘ladi. Karotenoidlar - ayrim
barglarda topilgan pigmentlarning yana bir turidir. Karotenoid ishlab chiqarish
nurga bog’liq emas, shuning uchun qisqartirilgan kunlar kamaymaydi.
Karotenoidlar to‘q sariq, sariq yoki qizil bo‘lishi mumkin, lekin barglardagi bu
pigmentlarning ko‘pchiligi sariq rangga ega. Ham antosiyaninlar, ham
karotenoidlar yaxshi miqdorda barglari to‘q sariq rangda paydo bo‘ladi.
Karotenoidlar bilan barglar, ammo ozgina antosiyanin sariq rangda ko‘rinadi.
Ushbu pigmentlar yo‘q bo‘lganda, boshqa o‘simlik kimyoviylari barg rangini ham
ta’sir qilishi mumkin. Masalan, ba’zi eman barglari jigarrang rang uchun mas’ul
bo‘lgan taninlar kiradi. Harorat, barglardagi
kimyoviy reaksiyalar darajasiga
ta’sir
qiladi, shuning uchun barglar rangida ishtirok etadi. Biroq, asosan, еngil ranglar
yig’ilib ketadigan ranglar uchun javob beradi. Quyoshli kuz kunlari eng yorqin
ranglar uchun kerak, chunki antosiyaninlar nur talab qiladi. Bulutli kunlar ko‘proq
sariq va jigarrang bo‘ladi.
69
Matn yuzasidan savol va topshiriqlar.
1.
Matnni o‘qing va unga sodda reja tuzing.
2.
Reja asosida matn mazmunini gapirib bering.
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- topshiriq - Gayubova komila anvarovna yulanova nargiza davlatovna akademik yozuv

5- topshiriq
. “Pochta tarixi” matnidan foydalanib BBB jadvalini to‘ldiring.
Nazorat savollari
1.
Insho rejasini tuzish qanday amalga oshiriladi?
2.
Sodda reja qanday bo‘ladi?
3.
Murakkab reja qanday tuziladi?
7-mavzu.
Konspekt. Konspekt turlari
Nazariy ma’lumot.
Tezis
Tezis
yunoncha
thesis
“qoida”,
“isbot” ma`nolaridagi so‘z bo‘lib, “ilmiy
asar, maqola, ma’ruza va sh.k.dagi asosiy g’oyalarning qisqa va lo‘nda bayoni”;
“haqiqat ekanligi isbotlanishi lozim bo‘lgan hukm, mulohaza, fikr”ni anglatuvchi
birlik sifatida qayd etilgan.
Bilaman
Bilishni xohlayman
Bilib oldim
70
Tezis mavzuning yoki matnning asosiy mohiyatini aks ettiruvchi qisqa
ifodalar bo‘lib, masalaning keng yoritilishini ta’minlovchi, yo‘naltiruvchi
xarakterga ega bo‘lgan umumlashma fikrlardir.
Tezis maqsadga ko‘ra ikki xil bo‘ladi:
1. Matn mazmunini yorituvchi tezis (bunday tezislarning mohiyati “Qanday
masalalar yoritilgan?” savoli mazmun-mohiyati bilan izohlanadi). Masalan,
konferensiyadagi ma’ruza matnining qisqacha mazmuni shu tipdagi tezisga misol
bo‘ladi.
2. Matn tuzishga yo‘naltiruvchi tezis (bunday tezislarning mohiyati
“Qanday masalalar yoritiladi?” savoli mazmun-mohiyati bilan izohlanadi).
Insho tezisi ikkinchi turga mansub bo‘lib, muallif fikrini jamlash, aniq
ifodalashga, izchillik maqsadiga xizmat qiladi. Insho tezisi reja bandlari asosida
shakllantiriladi. Reja bandlari insho mazmuniga qanchalik mos bo‘lsa, tezis ham
shu darajada mukammal bo‘ladi.
Tezislar butun insho mazmuniga yo‘naltiriladi, shu bilan bir qatorda yaxshi
insho yozishning muhim shartlaridan biri hisoblanadi. Fikrlar tezisi – bu inshoda
siz isbotlashga urinayotgan munozarali nuqtayi nazarlardir.
Tezislarning aniq bo‘lishi talab etiladi. Masalan, “O‘lim ular uchun fojia
emas, balki azobli hijrondan qutqarguvchi xaloskor, pirovard maqsadlari bo‘lmish
Yaratganning vasliga noil qiluvchi vosita edi”.
Ba’zan tezisda fikrlar borasida ma’lumot berish kerak bo‘ladi va bu bilan
birga o‘quvchi maqsadga yo‘naltiriladi: “Navoiy Laylining o‘limi, otasining
qahrini va ikki oila o‘rtasidagi nizolar tasvirini keltirib, yurak va aql doim turlicha
harakat qilishini namoyon qiladi”.
Demak, inshoning yuzga kelish jarayonini quyidagicha modellashtirish
mumkin:
mavzu-reja-tezis-matn.
Fikrni yozma bayon qilish bayon, saylanma bayon, konspekt, annotatsiya,
referat, sharh, biografiya, avtobiografiya, tavsifnoma, intervyu, ma’ruza, leksiya,
hisobot, maktub, kundalik kabi shakllardan iborat.
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Chervil Cottage - Customer satisfaction survey

Chervil Cottage. Q3 TOM:
Sorry? What was that again?
SHIRLEY:
Chervil. C-H-E-R-V for Victor I-L.
TOM:
Oh, that’s a herb, isn’t it?
SHIRLEY:
That’s right. It grows fairly wild around here. You could have that for the week you want for
£480.
TOM:
OK. So could you tell me something about it, please?
SHIRLEY:
Of course.
The building was built as a garage Q4 . It’s a little smaller than Granary Cottage.
TOM:
So that must sleep two people, as well?
SHIRLEY:
That’s right. There’s a double bedroom.
TOM:
Does it have a
garden?
Q5 SHIRLEY:
Yes,
you get to it from the living room through French doors, and we provide two
deckchairs. We hope to build a patio in the near future, but I wouldn’t like to guarantee it’ll
be finished by May.
TOM: OK.
SHIRLEY:
The front door opens onto the old farmyard, and
parking isn’t a problem – there’s plenty of room at the front for that Q6 . There are some trees and potted plants there.
....................................................................................................................................................................
TOM:
What about facilities in the cottage? It has standard things like a cooker and fridge, I presume.
SHIRLEY:
In the kitchen area there’s a fridge-freezer and we’ve just put in an electric cooker.
TOM:
Is there a washing machine?
SHIRLEY:
Yes. There’s also a TV in the living room, which plays DVDs too. The bathroom is too small
for a bath, so there’s a shower instead. I think a lot of people prefer that nowadays, anyway.
TOM:
It’s more environmentally friendly, isn’t it? Unless you spend half the day in it!
SHIRLEY:
Exactly.
TOM:
What about heating? It sometimes gets quite cool at that time of year.
SHIRLEY:
There’s central heating, and if you want to light a fire,
quiet times too, where their instructor

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quiet times too, where their instructorBog'liq Listening transcripts 230531 122425quiet times too, where their instructor
might tell them a story
Q4
that’s got something to do with cycling, or get them to play a
game together. It’s a lot of fun.
WOMAN:
It must be. Now,
what happens if there’s rain? Do the classes still run?
Q5
JAKE:
Oh yes. We don’t let that put us off – we just put on our waterproofs and keep cycling.
....................................................................................................................................................................
WOMAN:
And is there anything special Charlie should bring along with him?
JAKE:
Well, maybe some spare clothes, especially if the weather’s not so good. And
a snack
Q6
for break time.
WOMAN:
How about a drink?
JAKE:
No, we’ll provide that. And make sure he has shoes, not sandals.
WOMAN:
Sure. And just at present
Charlie has to take medication every few hours, so I’ll make
sure he has that.
Q7
JAKE:
Absolutely. Just give us details of when he has to take it and we’ll make sure he does.
WOMAN: Thanks.
JAKE:
Now, there are a few things you should know about Day 1 of the camp. The classes normally
start at 9.30 every morning, but on Day 1 you should aim to get Charlie here by 9.20. The
finishing time will be 12.30 as usual. We need the additional time because there are a few
extra things to do. The most important is that we have a very careful
check to make sure
that every child’s helmet fits properly
Q8
. If it doesn’t fit, we’ll try to adjust it, or we’ll find
him another one – but he must wear it all the time he’s on the bike.
WOMAN:
Of course.
JAKE:
Then after that, all the instructors will be waiting to meet their classes, and
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Konspekt - Gayubova komila anvarovna yulanova nargiza davlatovna akademik yozuv

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Gayubova komila anvarovna yulanova nargiza davlatovna akademik yozuvBog'liq Akademik yozuv o\'quv qo\'llanmaKonspekt.
Konspekt bayonning ko‘rinishlaridan biridir. Konspekt uch xil
bo‘ladi: to‘liq konspekt, qisqa konspekt, tezisli konspekt.
Biror asarni konspektlashtirilganda quyidagi tartibda ish ko‘riladi: avval asar
sinchiklab o‘qib chiqiladi, mazmun anglab olinadi va ko‘chirma qilish
mo‘ljallangan parchalarga belgilar qo‘yib chiqiladi (tagi chiziladi yoki boshqa bir
belgi qo‘yiladi). Konspektlash boshlanganda: a) muallifning ismi sharifi
(familiyasi, ismi, otasining ismi, taxallusi); b) asarning nomi, bosilgan shahri, yili;
v) asarning mazmuni - konspekt beriladi; g) manbadan olingan parchalarning beti
ko‘rsatiladi. Lozim topilganda muallifning ayrim fikrlariga munosabat bildiriladi.
To‘liq konspektda
matnning mazmuni muallif fikrlariga ba’zan bir
izohlovchi gaplar qo‘shish orqali keng bayon qilib beriladi. Ko‘p rejali asarlar
konspekt qilinganda, unda bayon etilgan hamma fikrlar izchil ko‘rsatiladi. Bunday
konspektni o‘qiganda asar haqida yеtarli mu’lumotga ega bo‘lish mumkin.
Qisqa konspektda matndagi eng muhim deb hisoblangan fikrlar bayon etiladi.
Voqealarning tafsilotlari berilmaydi. Muallif o‘z asarida, asosan nimalar ustida
to‘xtalganligi sanab o‘tiladi.
Tezisli konspekt
manbaning asosiy qoidalari eng muhim fikrlarni ajratib
olishdir. Tezis, odatda, ilmiy maqolalar, ma’ruzalarning siqiq mazmunidir. Tezisda
fikrlar ko‘pincha raqamlab boriladi. Tezisning hajmi eng ko‘p deganda 1-4
varaqdan oshmaydi. Lekin bu qat’iy chegara emas. Ba’zi siyosiy masalalarga
bag’ishlangan ma’ruzalarning tezisi kattaroq hajmda ham bo‘lishi mumkin.
Siqiq xulosa (rezyume). Siqiq xulosa ma’ruza yoki boshqa asarlarda keng va
atroflicha dalillar bilan bayon etilgan fikrlarning 3-4 gapli yakunidir. Muallif
rezyumeda kuzatish va mushohadalaridan yuzaga kelgan to‘xtamlarning eng
zarurlarini ko‘rsatadi.
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Ochiq kalitli kriptotizimlar

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Ochiq kalitli kriptotizimlar
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bet | 29/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
Ochiq kalitli kriptotizimlar
Simmetrik kriptotizimlardagi mavjud muammolardan biri – maxfiy kalitni xavfsiz uzatish va saqlash. Quyida kalitlarni uzatish va xavfsiz saqlash bilan bog‘liq muammolar bartaraf etilgan, asimmetrik yoki ochiq kalitli deb ataluvchi kriptotizimlar xususida so‘z boradi.
Ochiq kalitli kriptotizimlarda ma’lumotlarni shifrlash bir kalit bilan amalga oshirilsa (ochiq kalit deb ataladi), uni rasshifrovkalash boshqa bir kalit (shaxsiy kalit deb ataladi) bilan amalga oshiriladi. Shuning uchun, ochiq kalitli kriptotizimlarda simmetrik kriptotizimlarda mavjud bo‘lgan kalitlarni taqsimlash muammosi bartaraf etilgan. Biroq, ochiq kalitli kriptografik tizimlarning ham o‘ziga xos muammolari mavjud.
Ochiq kalitli kriptotizimlarni yaratishda “qopqonli” bir tomonlama funksiyalarga asoslaniladi. Bu o‘rinda “bir tomonlama” iborasining ma’nosi – funksiya bir tomonlama osonlik bilan hisoblanadi. Biroq, ushbu funksiyani teskarisini hisoblash juda ham murakkab (ya’ni, hisoblash mumkin emas). Bu yerda “qopqonli” deyilishiga asosiy sabab, hujumchi ochiq axborotdan (masalan, ochiq kalit) shaxsiy axborotni (masalan, shaxsiy kalitni) tiklashda foydalana olmaydi. Mazkur bir tomonlama funksiyalarga misol sifatida faktorlash amalini ko‘rsatish mumkin. Ya’ni, tub bo‘lgan ikkita p va q sonlarni generatsiyalash va 𝑁 = 𝑝 ∗ 𝑞 ni hisoblash oson. Biroq, N soni yetarlicha katta bo‘lganida uni ikkita tub sonning ko‘paytmasi shaklida ifodalash murakkab vazifa va u yuqori hisoblash imkoniyatini talab etadi.
Simmetrik kalitli shifrlarda ochiq matn 𝑃 shifrlansa, shifrmatn 𝐶 hosil bo‘ladi degan shartli belgilash kiritilgan edi. Ochiq kalitli shifrlash tizimlarida esa xabar 𝑀 shifrlansa, shifrmatn 𝐶 hosil bo‘ladi deb shartli belgilash kiritiladi.
Ochiq kalitli kriptografik tizimlardan foydalanish uchun, B tomon ochiq kalit va unga mos bo‘lgan shaxsiy kalit juftiga ega bo‘lishi talab etiladi. B tomonning ochiq kaliti kimga ma’lum bo‘lsa, u ma’lumotni shifrlashi mumkin. Shifrlangan xabarni ochish faqat shaxsiy kalit egasi bo‘lgan B tomonga joiz.
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Ochiq kalitlar infrastrukturasi (Public key infrastructure, PKI)

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Ochiq kalitlar infrastrukturasi (Public key infrastructure, PKI)
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bet | 38/111 | Sana | 20.05.2024 | Hajmi | 2,03 Mb. | | #246571 |
Ochiq kalitlar infrastrukturasi (Public key infrastructure, PKI).
Ochiq kalitli kriptografiya bilan bog‘liq bo‘lgan muammolardan yana biri
tomon biror maxfiy xabar 𝑀 ni 𝐵 tomonga yubormoqchi. Buning uchun
𝐴 tomon 𝐵 tomonning ochiq kalitidan foydalanadi. Biroq, g‘arazli niyatda bo‘lgan 𝐶 tomon o‘zining ochiq kalitini 𝐴 tomonga 𝐵 tomonni ochiq kaliti sifatida taqdim etadi. 𝐴 tomonni mazkur holatni tekshirish imkoniyati bo‘lmagani bois, unga ishonadi va maxfiy xabarni 𝐶 tomonning ochiq kaliti bilan shifrlaydi.
Ushbu muammoni oldini olish uchun ochiq kalitli kriptografik tizimlarda ochiq kalitlar infrastrukturasidan foydalaniladi.
Ochiq kalitlar infrastrukturasi yoki PKI real hayotda ochiq kalitli kriptotizimlardan xavfsiz foydalanish uchun talab etiluvchi barcha narsani o‘z ichiga oladi. PKI tarkibidagi barcha narsalarning birgalikda ishlashi juda ham murakkab jarayon, quyida ularning ayrim tashkil etuvchilari va PKI ning asosiy vazifalari bayon etilgan.
Raqamli sertifikat (yoki ochiq kalit sertifikati yoki qisqacha sertifikat) foydalanuvchining ismi va uning ochiq kalitidan iborat (amalda foydalanuvchiga va sertifikatga tegishli ma’lumotlar ham bo‘ladi) va u sertifikat markazi (certificate authority yoki CA) tomonidan imzolanadi. Masalan, 𝐴 tomonning sertifikati quyidagidan iborat bo‘ladi:
𝑀 = (A tomon nomi, 𝐴 𝑡𝑜𝑚𝑜𝑛𝑛𝑆𝑆𝑛𝑔 𝑜𝑐ℎ𝑆𝑆𝑞 𝑘𝑎𝑙𝑆𝑆𝑡𝑆𝑆) va 𝑆 = [𝑀]𝐶𝐴. Ushbu sertifikatni tekshirish uchun 𝐵 tomon {𝑆}𝐶𝐴 ni hisoblaydi va
𝑀 ga tengligini tekshiradi.
𝐶𝐴 tomoniga, odatda, ishonchli uchinchi tomon (trusted third party yoki TTP) sifatida qaraladi. Ya’ni, odatda 𝐴 tomon foydalanuvchi uchun shaxsiy va ochiq kalitlar juftini generatsiyalaydi. Shaxsiy kalit 𝐴 tomonga taqdim etilganidan so‘ng, 𝐶𝐴 dan o‘chirib tashlanadi. Ochiq kalit esa sertifikat shaklida taqdim etiladi. Agar 𝐵 tomon 𝐴 tomonga biror
ma’lumotni shifrlab yubormoqchi bo‘lsa, uning sertifikatidan foydalanadi. Buning uchun sertifikatdagi imzoni tekshirish talab etiladi. Bu esa o‘z navbatida 𝐵 tomonga 𝐶𝐴 ning ochiq kalitini (ya’ni, unga teng bo‘lgan sertifikatni) bilishi talab etadi. Demak, 𝐶𝐴 tomonning ochiq kaliti (yoki sertifikati) oldindan foydalanilayotgan tizimda mavjud va bu haqida barcha ma’lumotga ega bo‘ladi.
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particularly mention spreadsheets

SALLY:
So the second position might suit you better as far as the location goes; that’s for a warehouse
assistant and that’s in South London.
JOE:
Yes, that would be a lot closer.
SALLY:
And you’ve worked in a warehouse before, haven’t you?
JOE: Yes.
SALLY:
So as far as the responsibilities for this position go, they want someone who can manage
the stock, obviously, and also
deliveries.
Q6
JOE:
That should be OK. You’ve got to keep track of stuff, but I’ve always been quite good with
numbers.
SALLY:
Good, that’s their first requirement. And they want someone who’s computer literate, which
we know you are.
JOE: Sure.
SALLY:
Then they mention organisational skills. They want someone who’s well organised.
JOE:
Yes, I think I am.
SALLY: And