??? ??????????? OSI - PowerPoint PPT Presentation

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??? ??????????? OSI

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Title: ??? ??????????? OSI


1
?????? ???????
??????? ??????? ??????? ?????? ???? ??????
???????? ? ?????? ???????
??????? ? ????? ???? ????? ??????
????? ??? ???? ?????
  • ???? ?????? ????????
  • ????? 91

2
  • ?????? ???????? ?????????
  • ????????? ???????? ?????????
  • ????????? ????
  • ????????? ???????
  • ?????? ??????? ?????? ?? ????? ?? ????
  • ??? ??????????? OSI
  • ??? ??????????? TCP/ IP

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  • ????????? ???????? ?????????
  • ?????? ?????
  • ??? ??????????? ????????? ?? ????? ???????
  • ???? ????????
  • ???? ???? ?????? ?????? ???????
  • ?????? ?????? ?????

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???????? ??? -Bus
?????? ???? ????????? ?? ???? ?? ????? ??????
????? ?????? ?? ??? ? ??? ?????? ? ????? ????
14
???????? ???? -Ring) )
? ????? ????????? ?? ?? ?????? ????? ?? ?????? ?
?????? ???? ?????? ?? ??????? ?? ??????? ????
??? ? ?????? ???? ??? ???????? ???? ????
?????????? ??? ???? ?? ??????? ??? ????????
?????? ??????? ??? ?? ?? ???????
15
???????? ?????- (Star)
? ????? ???? ???????? ???? ???? ?? ??? ????? ?
??? ????? ??????? ????? ???? ?? ??? (Hub) ???
???????? ????.
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????? ??? ??? ???? (MAN)
???? ????? ???? ?? ??? ?? ????? ???? ???? ?? ????
?? ???? ????? ???? ???? ? ?? ???? MAN ????????
??????? . ??? ????? ???????? ? ???????? ?????
?? ???????? ???? ????. ????? ??? ???? ?????
?????? ?? ???? ???? ??????? ??????.


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????????? ??????????? ???? ?? ?? ?? ?? ??????
????, ?? ?????????? ???? ??, ????? ????? ?????
???? ?????? ???? ?? ???? ?? ?????? ?? ??????.
? ???? ?????? ?? ????? ???? ????? ? ?????? ?????
?????? ????? ?????
19
???? ??? ?? ??? (Wireless)
????? ???????
?????? ??????? ?? ???? ?????????? ????? ?
??????? ?? ???????? ?? ???????? ?? ?? ????? ??
???? ? ?? ?????? ????.
?????
????? ???? ??? ? ??? ?????? ??? ??? ????
?????
? ??? ????? ? ?????? ????? ? ??? ??? ??????
???? ? ????? ??????? ??
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?????? ??????? ?????? ?? ????? ?? ????
1- ???????? ????? Circuit Switching
2- ???????? ???? Message Switching
3- ???????? ???? ? ???? Packet Switching / Cell
Switching
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1- ???????? ????? Circuit Switching
???? ?? ???? ???? ????? ???? ??????? ?????? ???
??????? ? ?????? ? ? ??? ????? ??????? ??????
???? ???????? ???? ?? ?? ????? ??????? ? ??????
????? ????? ???? ????? ???? ?? ?????
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2- ???????? ???? Messeage Switching
???? ?????? ?????? ??????? ? ????? ?????
????????? ?? ???? ????? ??? ? ????? ?????
??????? ???? ?? ???? ?? ??? ?? ????? ?? ?? ????
????? ???? ??????? ??????? ? ?????? ???? ????
???? ?? ???? ????? ? ?????? ????? ????? ????? ??
???? ???? ? ?????? ????? ?? ????
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????? ???? ???? ??????? ??????? ?? ????? ???????
?? ??? ???? ? ????? ?? ???? ?? ????? ???????
???? ???? ??????? ?? ?? ??? ??????? ?? ????? ?????
25
????? ????? ???? ?? ??? ???????? ???? ???? ?? ???
???????? ???? ? ???? ?? ???? ????? ???? ? ????
????? ?? ?? ???? ????? ?? ??? ???????? ?
???? ??? ????? ????? ?? ???? ?? ?? ???? ?????? ?
???? ?? ????? ???? ??? ???? ???? ?
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???????? ????? ?? ?????? ??????? ???? ? ????
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????? ?????? ???? ?? ???????
Simplex ?????? ?????? - ? ????? ????? ?????? ?
????? ????? ??????? Half duplex?????? ??????
????????? - ? ?? ?? ????? ?? ????????? ???????
????? ? ?? ?????? ??? ?? ????? ?????? Full
duplex ?????? ?????? ?????? - ? ?????? ?? ????
?????? ????? ???? ????????
31
??? ??? ??????? OSI ?? ?????? ????????? ????? ISO
  • ? ???? ?????? Physical layer
  • ? ???? ????? ??????? Data link layer
  • ? ???? ???? Network layer
  • ? ???? ?????? Transport layer
  • ????? ???? Session layer
  • ? ???? ????? ( ????? ) Presentation layer
  • ? ???? ?????? Application layer

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??????? ?????? ????? ?? ???? ?? ???
???? ?????? Application layer ???? ???????? ???????
???? ?????? Transport layer ???? ?????? ?????? ?? ?????? (Host to Host) ???? ?????? ????? ??????? (End to End Connection)
???? ???? Network layer ???? ??????? ???? ???????? ???????
???? ?????? ?? ???? Network Interface ???? ?????? ?? ???? (Host to Network) ???? ???? ????
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???? ??
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  • ?????? ???? IP
  • ????? ?????? ? ???????? IP
  • ???????? ??????? ? ??????? ????
  • ??????? ??? ????
  • ?????? ICMP
  • ????????? ARP,RARP,BOOTP

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  • ??????? ?? ???????? ?????
  • ???? ???????? ? ????????
  • ????? ?? ?????? ????????

???? IP
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??????? Router))
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???? ????? 4 ?????? Version 0100 IP ????
????? 6 ?????? IP
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???? Type of sevice
????? ????? ?????? ???? IP
?????? ????
P2 P1 P0 D T R - -
???? ???? ???? ???? ???? ???? ????? ???? ????? ?????? ??????? ?????????? ??????????
???????? ??? 1 ???? ????? ?????? ?? ??? ????? ???
?????? ???? ????? ???? ?????????
91
???? Total Length
  • ???? 16 ????
  • ???? ????? ??? ?? ???? IP ( ????? ?????? ??????
    ? ????? ????)
  • ?????? ??? ?? ???? IP 65535 ????

???? Identification
  • ???? 16 ????
  • ???? ????? ????? ?? ???????? ????

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???? Fragment Offset
???) ??? DF (( Dont Fragment ?? ?? ??? ??? ???
?? ?? ????IP ??? ???????? ????? ???? ???? ?????
???? ?? ?????
?) ??? MF (More Fragment ) MF0 ???? ?????
????? ???? IP ?? ?? ???????? MF1 ???? ?????
???? ?? ?? ????????
  • ?) Fragment offset
  • 13 ????
  • ???? ????? ????? ????? ?? ???? ???? ????????
    ????? ???
  • ??????????? ????? ?? ???????? 8192

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15
0
0
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Host ID
192.0.0.0 to 239.255.255.255
Network
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?? ??? ???? ??????? ???? IP ?? ??? ???? ?? ??????
??? ???? ?? ???? ??? ?? ????? ? ???????? ????.
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Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum 0 Code 0 Code 0 Code 0 Code 0 Code 0 Code 0 Code 0 Code Type4 Type4 Type4 Type4 Type4 Type4 Type4 Type4
Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused Unused
Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram Internet Header 64 bits of Original Data Datagram
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Identifier
Sequence Number
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Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum 0Code 0Code 0Code 0Code 0Code 0Code 0Code 0Code Type? Type? Type? Type? Type? Type? Type? Type?
Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier Identifier
Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp Originate Timestamp
Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp Receive Timestamp
Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp Transmit Timestamp
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Hardware Type Hardware Type
Protocol Type Protocol Type
Protocol Address Length Hardware Address Length
Operation Code Operation Code
Source Hardware Address Source Hardware Address
Source IP Address Source IP Address
Destination Hardware Address Destination Hardware Address
Destination IP Address Destination IP Address
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??????? ?????? ??? ???? ??????? ?????? ?? ?? ???
???? ??????? ??????? ?????? ????????? ? ????????
?????? ?? ??? ???? ???????????? ????????
??????? ???? ???? ???? ????? ????? ???? ?????????
?? ??????? ?? ????? ?? ???? ?? ????? ????.
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??? vc
6. Receive data
5. Data flow begins
4. Call connected
3. Accept call
1. Initiate call
2. incoming call
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??? Datagram
1. Send data
2. Receive data
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Dijkstras Algorithm
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????? ????? ?? ???????
  • ?? ?????? ??? ????? ???? ??? ?? ?????? ?? ?????
    ???? ???? ?? ???.

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????? ????? ?? ???????
  • ????? ???????? ?? ??????? ???? ??? ?????? ?? ????
    ??????????? ???? ????? ??????? ? ?? ???? ?????
    ????? ???? ?? ?? ???? ????.

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???? ??????? ?? ?????? ?????? ?????? ???? ????
?? ?????? ????? ????????
????? ????? ?? ???? ????? ??????? ????? ???? Zones ????? ???? Clusters ????? ????? Regions
720 720 - - 1 ???????? DV ???? ???????????
53 30 - - 24 ???????? DV ?? ??????????? ???????
25 10 - 8 9 ???????? DV ?? ??????????? ???????
19 4 4 5 9 ???????? DV ?? ??????????? ???????
?????? ?????? ???? ???????? ?? ?????? ?????
???????
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?????? BGP ?????? ???????? ????? The Exterior
Gateway Routing Protocol
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?????? ???? ?? ?????? ??? ?????????? BGP
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????????? ???? ??????
UDP User Datagram Protocol
TCP Transmisson Control Protocol
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  • ??? ????? ???? ????? ? ????? ???????

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Port
Protocol
Use
21
FTP
File transfer
23
Remote login
Telnet
E-mail
25
SMTP
69
Trivial File Transfer Protocol
TFTP
Finger
Lookup info about a user
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80
World Wide Web
HTTP
POP-3
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Remote e-mail access
USENET news
119
NNTP
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?????? ???? ??? ?????? TCP
  • TPDU Transport Protocol Data Unit ???? ?????
    ??? ?? ???? ?????? ????TCP

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?????? Flag
??? URG
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????? ???? 1 ?????????? ????? ???? ????? ?????
?? ???? Acknowledgement Number
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Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address Source IP Address
Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address Destination IP Address
TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length TCP Segment Length 00000110 00000110 00000110 00000110 00000110 00000110 00000110 00000110 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
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????? ??? ?????
???????? ????? ?? ????? ??????? ???????? ????? ?? ????? ???????
????? ????? ????? ???? ?? ?? ????? ??? ??? ???? ????? Ack ?? ??????? ???. SND.UNA
????? ????? ????? ???? ?? ???? ?? ?? ?? ????? ?? ??? ?? ???? ???? ?? ???? ????? ???. SND.NXT
????? ???? ???? ?? ???? ????? SND.WND
????? ????? ????? ???? ??? ??????? ?? ????? ?????? ??????? ??? ???. SND.UP
SND .WL1
SND.WL2
????? ????? ????? ???? ???? ?? ???? ??? ?? ?????? ??????? ???? (Push) ???. SND.PUSH
????? ????? ??????? ????? ???? ??? ??????? ?? ?? ??? ?????? ?? ??? ?? ????? ??????. SND.ISS

???????? ????? ?? ?????? ??????? ???????? ????? ?? ?????? ???????
????? ????? ????? ???? ?? ???? ???? ?? ?? ?? ????? ?? ??? ?????? ?????? ???? ????. RCV.NXT
????? ???? ???? ?? ???? ?????? RCV.WND
????? ????? ????? ???? ??? ??????? ?? ???? ?????? ??? ????? ????? ??? ???. RCV.UP
????? ????? ??????? ????? ???? ??? ?????? ?? ?? ??? ?????? ?? ??? ?? ????? ??????. RCV.IRS
???????? ??????? ???? TCP
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??????
???????
???? ???? ????? ????? ?? ?????? TCP
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RTTnewRTTold4Dnew Dnew?.Dold(1-?).(RTTold-M)
?7/8 ????? ????? D ???????? ??? ????.
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  • ???? ????? ????????? ???
  • ????? ??? ???? ? ????? ????? ???
  • ?????? ????? ?? ????? ????????? ???
  • ????????? ??????
  • ????????? ???????
  • ????????? ?????
  • ?????? ???? ???????? ?? ????? ????????? ???
  • ???? ???? ?? ??????????????? ??? ????
  • ???? ?????? ???? ?? ???????
  • ???? ?????? SNMP

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?????? ?? ????? ????? ??????? ??????? ???????
?????? ??? ???? ????? www.ibm.com
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Root
2
Query for address of .Com name server
Local Name Server
Referral to .Com NameServer
4
Query of address of microsoft.com Server
.Com
.edu
5
6
Microsoft.com
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Root
Root Name Server
3
6
.com
.edu
8
Microsoft.com
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Authoritative data for cs.vu.nl cs.vu.nl. 86400 IN SOA star boss (952771,7200,2419200,86400) cs.vu.nl. 86400 IN TXT Faculteit wiskunde en informatica cs.vu.nl. 86400 IN TXT Virje universiteit Amsteradam cs.vu.nl. 86400 IN MX 1 zephyr.cs.vu.nl. cs.vu.nl. 86400 IN MX 2 top .cs.vu.nl. flits.cs vu.nl. 86400 IN HINFO SUN UNIX flits.cs vu.nl. 86400 IN A 130.37.231.165 flits.cs vu.nl. 86400 IN A 192.31.231.165 flits.cs vu.nl. 86400 IN MX 1 flits.cs.vu.nl flits.cs vu.nl. 86400 IN MX 2 zephyr .cs.vu.nl flits.cs vu.nl. 86400 IN MX 3 top.cs.vu.nl www.cs.vu.nl. 86400 IN CNAME star.cs.vu.nl ftp.cs.vu.nl. 86400 IN CNAME zephyr.cs. vy.nl rowboat IN A 130.37.56.201 IN MX 1 rowboat IN MX 2 zephyr little-sister IN A 130.37.62.23 IN HINFO Mac MacOS laserjet IN A 192.31.231.216 IN HINFO HP LaserJet IIISi Proprietary
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Header
Question
Answer
Authority
Additional
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???????? ??? ?????? ??? ?????
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??????? ???? ????
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Applet ????
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?? ??? ????? ?? ????
?????????? ????
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