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

1) Connecting a private network to the Internet can expose your data to malicious attacks.

2) The first generation of firewalls appeared in 1988.

3) A firewall filters only outbound traffic.

4) A firewall can trigger alarms at the attempt of hostile or unauthorized entry.

5) Firewall is a secure feature impossible to bypass.

Vocabulary

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

1) обычный пользователь

2) подвергать данные нападению

3) осознавать опасности

4) враждебное вторжение

5) высокоразвитый

6) связи между зарегистрированными абонентами

7) точка соединения

8) соответствовать определенным критериям

9) входящий и исходящий трафик

10) запускать тревожную сигнализацию

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

1) available a) entering the system without being

given the permission

2) implication b) a computer connected to a network

and providing facilities to other

computers and their users

3) unauthorized access c) obtainable or accessible

4) router d) a property, quality, or feature

representing a person or thing

5) host e) a device in a network that handles

message transfers between computers

6) to forward f) something associated or involved, as

implying a potential situation or outcome

7) attribute g) to send forward or pass on to an

ultimate destination

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

1) benefit or gain

2) safety or protection

3) to authorize

4) communications

5) to inspect or monitor

6) incoming

7) open or unrestricted

8) to decline

9) to connect

10) relying on

6. Read the text below and choose the best option for each gap. Different Types of Firewalls

Firewalls fall into four broad categories: (1) ……………. filters, circuit level gateways, application level gateways and stateful multilayer inspection firewalls.

Packet filtering firewalls work at the network level of the OSI model, or the IP layer of TCP/IP. They are usually part of a router. A router is a device that receives packets from one network and (2) ……………… them to another network. In a packet filtering firewall each packet is compared to a set of criteria before it is forwarded. Depending on the packet and the criteria, the firewall can (3) ………… the packet, forward it or send a message to the originator. Rules can include source and destination IP address, source and destination port number and protocol used. The advantage of packet filtering firewalls is their low cost and low (4) ………….. on network performance.

Circuit level gateways work at the session layer of the OSI model, or the TCP layer of TCP/IP. They monitor TCP (5) ………………… between packets to determine whether a requested session is legitimate. Information passed to remote computer through a circuit level gateway appears to have originated from the gateway. This is useful for hiding information about protected networks. Circuit level gateways are relatively inexpensive and have the advantage of hiding information about the private network they protect. (6) ……………………., they do not filter individual packets.

Application level gateways, also called proxies, are similar to circuit-level gateways except that they are application specific. They can filter packets at the application layer of the OSI model. Incoming or outgoing packets cannot access services for (7) …………. there is no proxy. In plain terms, an application level gateway that is configured to be a web proxy will not allow any ftp, gopher, telnet or other traffic through. They offer a high level of security, but have a significant impact (8) ………. network performance.

Stateful multilayer inspection firewalls combine the aspects of the other three types of firewalls. They filter packets at the network layer, determine whether session packets are (9) legitimate and evaluate contents of packets at the application layer. They allow direct connection between client and host, alleviating the problem caused by the lack of transparency of application level gateways. They rely on algorithms to recognize and process application layer data instead of running application specific proxies. Stateful multilayer inspection firewalls offer a high level of security, good performance and transparency to (10) ……………… users. They are expensive however, and due to their complexity are potentially less secure than simpler types of firewalls if not administered by highly competent personnel.

1. a) package b) packet c) pack

2. a) forwards b) onwards c) mails

3. a) fall b) drop c) refuse

4. a) impact b) impression c) pressure

5. a) handclasping b) handgripping c) handshaking

6. a) on the one hand b) on the other hand c) anyway

7. a) what b) whom c) which

8. a) of b) for c) on

9. a) legitimate b) genuine c) authentic

10. a) final b) end c) ultimate

7. Complete the following sentences with one, another, other, any, or each:

a) A router is a device that receives packets from ………… network and forwards them to ……………. network.

b) ………… packet is compared to a set of criteria before it is forwarded.

c) On the …………. hand, circuit level gateways are relatively inexpensive, on the …………….. hand, they do not filter individual packets.

d) A web proxy will not allow …………. ftp, gopher, telnet or …………. traffic through.