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Internet () .
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3. OSI.
( ) OSI .
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(Presentation) - (, ) .
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(Transport) - .
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(. data link layer) , . , , , , , ( ) . , .
IEEE 802 : MAC (. media access control) , LLC (. logical link control) .
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(coaxial cable);
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(fiber optic).
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2 | 10 / 2 / |
, . , , , , / . . " " (Thicknet) " " (Thinnet). 10 /. 185 500 .
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6. IEEE 802
IEEE 802.X - OSI - . , . , , , .
, . (Data Link Layer) :
- (Logical Link Control, LLC);
- (Media Access Control, MAC).
MAC - . , . , - LLC, , , . MAC, . , Ethernet, Fast Ethernet, Gigabit Ethernet, Token Ring, FDDI, l00VG-AnyLAN.
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IEEE 802 , .1:
.1 IEEE 802
, 802 , . . : MAC . , MAC ( Ethernet Token Ring, , ArcNet, FDDI, l00VG-AnyLAN).
LLC, , . LLC 802.2. , 802, LLC, 802.2, FDDI, ANSI.
, 802.1. . 802.1 , IEEE 802 OSI. 802.1, , . (internetworking). , 802. ID, /, 802.1, , Ethernet FDDI, Ethernet Token Ring . . , 802.1, . , 802.1Q, VLAN .
802.3,802.4,802.5 802.12 , , . , 802.3 Ethernet, Digital, Intel Xerox ( Ethernet DIX), 802.4 | ArcNet Datapoint Corporation, 802.5 Token Ring IBM.
7. . MAC LLC.
- - . , . , , . , . Ethernet, TokenRing, FDDI.
LLC , . LLC , , .. .
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: - (logical link control, LLC) - (media access control, MAC). LLC .
MAC ( ) MAC- , . , MAC , , , . . , MAC .
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802.2. LLC :
1) LLC 1 .
2) LLC2 , .
3) LLC3 , , .
8. Ethernet.
Ethernet, Xerox. /. Ethernet IEEE 802/3. IEEE 802/4, .
Ethernet . , 1996 . 85% Ethernet.
Ethernet . Ethernet, .
1. Thick Ethernet ( " " ); 10Base-5, "10" 10 /, "5" - ( ), .. 500 ; : 5; 100; 2,5 . , () .
2. Thin Ethernet ( " " , cheapernet); 10Base-2: 5; 185 ; 30; 0,5 ; 10 /.
. 4.3.
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4. Fiber Optic Ethernet ( ), 10Base-F; "-", , . - 2...4 . , , , .
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, . t . t , , ( - ), t<T.
9. Token Ring FDDI.
Token Ring FDDI , Ethernet . : , , , . , FDDI , , .
Token Ring FDDI , Ethernet. Token Ring, (. 1), , , . Token Ring, IBM, 4 /, 16 /. . Token Ring ( FDDI) - , Ethernet.
Token Ring , , , , , , . , . , , Ethernet, ( , , ). , . , , , , .
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Token Ring ( . 1) . , . , .
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(. . switch ) , . () OSI. . .
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Ethernet.