2. Say if the following statements are True or False.

1) The work of firewalls helps to understand the interaction between different layers of a network.

2) The Defense Advanced Research Project Agency concluded to create the OSI reference model.

3) Firewalls that operate at the transport layer are able to impart or refuse access depending on more sophisticated criteria.

4) Network architecture is designed around a five layer model.

Vocabulary

3. Find English equivalents of the following phrases in the text.

1) сложный

2) сетевой экран

3) ответственность

4) базовая модель

5) сочетаемость

6) пакет маршрутизации

7) управлять

4. Match the words 1-7 with the definitions a-g.

1) architecture a) a standard by which something can

be judged or decided

2) protocol b) to remove from; separate

3) criterion c) a system of computers to share

information

4) application d) the overall design or structure of a

computer system

5) dissociate e) a standard procedure for regulating data

transmission between computers

6) network f) to connect or join together; combine

7) associate g) a computer program designed for a

specific task or use

5. Find the words in the text which have the similar meaning to the words below.

1. liability

2. relation

3. refuse

4. comparable

5. maintain

6. modernized

7. complicated

6. Read the text below and choose the best option for each gap. Secure Tunnel Information

Tunneling, also known as "port forwarding", is the transmission of data intended for use only within a private, usually (1) …….……. network through a public network in such a way that the routing nodes in the public network are unaware that the transmission is part of a private network. Tunneling is generally done by (2) …………… the private network data and protocol information within the public network transmission units so that the private network protocol information appears to the public network as data. Tunneling allows the use of the Internet, which is a public network, to (3) ………….. data on behalf of a private network.

A secure tunnel creates an encrypted data link between two computers or two networks. Encrypting the data between two points allows it to travel over the public Internet with far less risk of data (4) …..……….. Tunnels allow for secure links between, for example, a corporate network and someone working at home.

Secure tunneling has been possible since the advent of Internet protocol (IP) networking. The first commercially (5) …………… tunneling protocol was, according to IBM's iSeries Information Center, the Secured Socket Layer (SSL) encryption as implemented for browser-to-server communication by Netscape in 1994. Later SSL implementations increased security through more complex encryption algorithms. SSL was designed to support tunneling by other applications, such as telnet and ftp. In the (6) ..…..……. years, a number of different protocols have developed using different algorithms and architectures, including secure shell (SSH) and secure shell 2 (SSH2).

One type of secure tunnel is to encrypt transactions for web payment. By creating an SSL tunnel, credit card information is rendered unreadable by anyone other than a customer and a company's payment server. This technology also allows email data on servers to remain (7) ………….. until they arrive at their destination. Secure SSL tunnels are indicated in your browser bar by the prefix https. Unencrypted connections are indicated by http.

A second type of Internet tunnel is used to bypass firewalls, like those used in China and Iran. By using an encrypted link to a proxy server outside of the firewalled area, the data and destinations served to the client computer is (8) …….……. and unreadable by the firewall. A good example of a proxy service with a secure tunnel is Secure-Tunnel.com.

Virtual Private Networks (VPN) are often used by companies to encrypt all Internet traffic between an employee's computer at home and corporate networks. There are many different types of VPN networks, such as IPSec or Point to Point Tunneling Protocol (PPTP).

1. a) corporate b) incorporate c) personal

2. a) forming b) encapsulating c) referring

3. a) move b) convey c) count

4. a) modification b) input c) interception

5. a) available b) engaged c) vacant

6. a) intervening b) last c) recent

7. a) common b) public c) private

8. a) encrypted b) available c) open

7. Revise grammar statement of Present Simple and do the following task.

Go / forget / not eat / live / play / have / finish / not speak

1. Alex_____________ to the gym three times a week.

2. My cousin ________ in the States.

3. I ________________ French and Spanish.

4. The exam _________ at 12.30 exactly.

5. Nadia____________ very healthy food.

6. My dad ___________ the guitar.

7. We_______________ a karate lesson on Friday afternoon.

8. Make some notes about types of tunneling and its use in information technology.

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