5.10 Прочитай, переведи текст cryptography и расположи абзацы в правильной последовательности:

A) Cryptography provides information security with other useful applications as well including improved authentication methods, message digests, digital signatures, non-repudiation, and encrypted network communications. Older less secure applications such as telnet and ftp are slowly being replaced with more secure applications such as ssh that use encrypted network communications. Wireless communications can be encrypted using protocols such as WPA/WPA2 or the older (and less secure) WEP. Wired communications (such as ITU‑T G.hn) are secured using AES for encryption and X.1035 for authentication and key exchange. Software applications such as GnuPG or PGP can be used to encrypt data files and Email.

B) Cryptography can introduce security problems when it is not implemented correctly. Cryptographic solutions need to be implemented using industry accepted solutions that have undergone rigorous peer review by independent experts in cryptography. The length and strength of the encryption key is also an important consideration. A key that is weak or too short will produce weak encryption. The keys used for encryption and decryption must be protected with the same degree of rigor as any other confidential information. They must be protected from unauthorized disclosure and destruction and they must be available when needed. Public key infrastructure (PKI) solutions address many of the problems that surround key management.

C) Information security uses cryptography to transform usable information into a form that renders it unusable by anyone other than an authorized user; this process is called encryption. Information that has been encrypted (rendered unusable) can be transformed back into its original usable form by an authorized user, who possesses the cryptographic key, through the process of decryption. Cryptography is used in information security to protect information from unauthorized or accidental disclosure while the information is in transit (either electronically or physically) and while information is in storage.

PREPOSITIONS

Предлоги места и движения:

1.Предлог at употребляется:

• когда подразумевается конкретное место нахождения: The postman is at the door.

• где происходит событие: There were a lot of people at the party.

• в выражениях: at school/university/college, at work, at home, at the top of, at the bottom of, at sea = on a voyage, at the station/airport, at the seaside, etc.: I live at 18 King Street (Но: in King Street)

• когда речь идет о чьем-либо доме или бизнесе: at Joan’s, at the doctor’s, at the newsagent’s.

2.Предлог in употребляется:

• в выражениях: in the middle, in the sea, in the sky, in bed, in hospital, in prison, in a newspaper/magazine/book, in a picture/photo, in a street, in the world, in the lesson, in the country, in one’s hand, etc.

• с названиями городов, столиц, стран и континентов: in Stratford, in Milan, in Egypt, in Asia

NB: in –внутри, в самом здании, at – абстрактно, о действии: It was very hot in the cinema (в здании кинотеатра). My parents are at the cinema (смотрят фильм).

3.Предлог on употребляется в выражениях: on the left/right, on a platform/page/screen/island/ beach/coast, on a map, on a farm, on a menu, on the first/second/… floor, on a chair (Но: in an armchair), on/at the corner of a street (Но: in the corner of a room, go/run/… round a corner)

4.Когда речь идет о путешествиях разными видами транспорта употребляется предлог by: by car/by bus/by train/by taxi/by plane/by boat, но on foot. By не употребляется, когда есть артикль, личное местоимение и с притяжательным падежом: on the train, in your car, on the eight o’clock bus/in a taxi/on the plane/in Richard’s car.

Предлоги времени:

• Предлог from … to/till/until употребляются для выражения длительности: She works from 9 to/till/until 5 every day.

• Предлог in употребляется чтобы сказать сколько времени займет действие: He finished the test in half an hour. Our new flat will be ready in a month.

Предлоги времени не употребляются с today, tomorrow, tonight & yesterday: I’ll see you tomorrow; с this, last, next, every, all, some, each, one & any: He has a music lesson every Tuesday.