1. Vocabulary
focus. Sudy the words andword combinations, practise their translation, spelling. Check your knowledge
in the test. Play vocabulary game and set your own vocabulary game record.
2. Watch the video and put the words into
the gaps in the text
Each (1)____
is limited in its size. The mail-room must decide how to divide the
information and how to (2)____ it. Every package needs a (3)___, containing
important information such as sender’s address, receiver’s (4)____ and the
type of packet (5)___. Because this particular packet is going out onto the
Internet, it also gets an address for the (6)____ which has a special
function as we'll see later.
The packet
is now (7)____ onto your local area network or (8)____. This (9)____ is used
to connect all the local computers, (10)____, (11)_____ etc. for information
exchange within the physical walls of the building. The highway of the LAN is
packed with all types of information. These are IP packets, Novell packets,
Apple Talk packets. The local router reads the address and if necessary lifts
the packet onto another network. As the packets leave the router, they make
their way into the corporate (12)____ and head for the router (13)____. As
packets arrive at their destination they are picked up by the network (14)____,
ready to be sent to the next level, in this case, the proxy. The proxy is
used by many companies as a sort of (15)____ in order to lessen the load on
their Internet connection and for security reasons as well.
The (16)____
opens the packet and looks for the web address or URL. Depending upon whether
the address is (17)_____ the packet is sent on to the Internet. There are,
however, some addresses which do not meet with the (18)____ of the proxy,
that is to say corporate or management guidelines. These are summarily dealt
with. For those who make it, it's on the road again. Next up - the (19)____.
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package
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proxy server
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IDS
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address
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packet
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label
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routers
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middleman
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intranet
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switch
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network
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interface
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launched
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LAN
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printers
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acceptable
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proxy
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firewall
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approval
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The corporate firewall serves two purposes.
It prevents some rather (20)____ things from the Internet from coming into
the intranet. And it can also prevent sensitive corporate (21)____ from being
sent out to the (22)____. Once through the firewall, a router picks up the
packet and places it on to a much narrower road or (23)____, as we say.
Obviously, the road is not (24)_____ enough to take them all.
Now you
might wonder what happens to all those packets which don't make it along the
way. Well, when IP doesn't receive an (25)___ that a packet has been received
in due time, he simply sends a replacement packet. We are now ready to enter
the world of the Internet, a (26)____ of inter-connected networks which spans
our entire (27)____. Here, routers and switches establish links between
networks. The paths our packets take maybe via (28)____, telephone lines, (29)____
or even trans-oceanic cable. Near the end of our destination, we'll find
another firewall. The firewall is designed to let in only those packets that
meet its (30)____. This firewall is operating on ports 80 and 25. Port 25 is
used for mail packets, while port 80 is the entrance for packets from the
Internet to the Web (31)____. Inside the firewall, packets are screened more (32)____,
some packets make easily through customs while others look just a bit
dubious.
For those packets lucky enough to
make this far, the journey is almost over. It's just to line up on the (33)
to be taken up into the web server. One by one, the packets are received,
opened and (34)____.
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information
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Internet
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broad
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bandwidth
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nasty
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globe
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acknowledgment
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server
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wireless
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spider web
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criteria
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satellite
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thoroughly
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unpacked
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interface
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3. Answer the questions.
1. What information does label
contain?
2. What is local area network
or LAN used for?
3. What is proxy used for?
4. What purposes does
corporate firewall serve?
5. What are the assignments of ports 25 and 80?
4.
Mark the following statements as True or False.
1. Each
packet is unlimited in its size.
2. Every
package needs a label, containing important information.
3. The
highway of the LAN is packed with only IP packets.
4. The
proxy is used by many companies as a sort of middleman in order to increase the
load on their Internet connection.
5. The
proxy opens the packet and looks for the web address or URL.
6. Next
level after proxy is the firewall.
7. When
mister IP doesn't get an
acknowledgment that a packet has been received i n due time, he simply sends a
replacement packet.
8. Our
packets are transferred only via telephone lines.
9. Firewall
is operating on six ports.
10. Inside the
firewall, packets are screened more thoroughly, some packets make easily
through customs while others look just a bit dubious.
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