, - . . , , . . .
- S/D (rrir-Sence ultiple-Aess with Collision Detection), " ."
(Carrier Sense - CS)
, Ethernet, . , .
, . . , .
(Multiple Access - MA)
Ethernet - . Ethernet .
, .
(Collision Detection - CD)
, , , .. . , , . .
, , . . , 30% . 50% .
Ethernet.
Ethernet . , . .
Ethernet :
1. Ethernet, ;
2. 802.3, : MAC LLC.
(Media Access Control) . , .
|
|
|
LLC (Logical Link Control) . . IEEE-802.2, IEEE-802.1Q
Ethernet, LLC, Novell IPX/SPX. 802.3
:
1. Ethernet
2. 802.3
1) Ethernet
1. - 8 .
2. - 6 - , . , , . - , . , , - , .
3. - 6 - . .
4. - 2 . .
5. - 1474 . . , .
6. - 4 . . 6. , .
2) 802.3
1. - 8
2. - 6 -
3. - 6 -
4. - 2 . ( 1500 )
5. - . . :
5.1 LLC 4 :
DSAP 1
SSAP 1 ( )
CTRL 2 :
1)
2)
5.2 .
6. - 4 .
| DSAP | SSAP | CTRL |
Ethernet:
10BASE5. SMA/CD. 10 /. BASE , . 5 .
|
|
|
100 . . AUI-. ., .
10BASE3 ─ . . 300 . BNC. , .. 5 , .
10BASE2 ─ CSMA/CD, 10 / 200 . .
BNC, . () 10BASE3.
10BASET CSMA/CD. 10BASET, IEEE 1990 , 10 / . () 100 .
RJ-45. . ( thernet ). : ─ , ─ , . , .
Ethernet : Ethernet (, Ethernet ThinLAN ( ) Ethernet ThickLAN ( ). : 0.2 , ─ 0.4 .
Token Ring.
IEEE - 802.5. . . . , . 25 /.
Token Ring:
IBM. :
1.
2. .
.
, , . . : , .. . . , . . -. , .
:
, , ,
, ,
, , ,
,
Token Ring . . , .
|
|
|
.. 3 (). 3 , (RRR).
Token Ring . :
1. Rr ;
2. Pr ;
3. Sr ─ Pr;
4. Sx ─ ;
5. Pm ─ , .. .
Token Ring
1. .
| SD | ED |
SD , ED .
2. Token Ring
| SD | AC | ED | ||||||
| P | P | P | T | M | R | R | R | |
AC . : PPP ; RRR ; T (0 , 1- ); M , .
