PON , (, ) OLT (Optical Line Terminal) ONU (Optical Network Units) . , PON - . , PON . PON 32 ONU CO (entral Office), , .
PON - " " SDH. PON , (subscriber). ONU , , (. 1).
, (WDM). PON . WDM SONET/SDH, / , .
PON , -. , , (TDM).
PON , . , .
PON TMD- ONU (Optical Network Unit) OLT (Optical Line Terminal) .
. 1.
. 1.
, N L . (a) - 2N N*L ( , ; ).
, . L ( ), 2N+2, . .
, . 2x2, 3 . , 0,1 1,0 .
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(splitter), - (combiner). . 2.
(a) | (b) |
(c) | (d) |
. 2. PON
PON OLT (Optical Line Terminal) ONU (Optical Network Unit). OLT CO WAN (). ONU (FTTH - Fiber To The Home FTTB - Fiber to The Building), ( FTTC - Fiber To The Curb).
PON :
- PON OLT ON ( 20 ).
- PON .
- PON ( 10 /c -> IEEE P802.3av).
- , PON .
- PON , . PON .
- , PON .
upstream ONU (WDM), ONU . ( ), . WDM- , OLT, . ONU: ONU, , ONU. ONU , , . ONU, ONU PON. ONU , . WDM PON .
(downstream - ) (upstream - ), - (peer-to-peer). , downstream upstream . SDM (Space Division Multiplexing), PON. , . : 1310 (λ1) upstream 1550 (λ2) downstream (. 3). .
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. 3. PON
, OLT , 1310 , , .
- CO ONU, PON ONU . , OLT .
ONU , , OLT ONU . , ONU , OLT ONU, , ONU .
, ONU . , . ONU, OLT, ONU. , ONU . , , . , .
PON , - (P2MP) . , EPON, , , . PON , .
1 PON
APON, ATM PON | BPON, Broandband PON | EPON, Ethernet PON ( GEPON, 10GEPON) | GPON Gigabit PON | |
/ | ITU-T SG15/ FSAN | ITU-T SG15/ FSAN | IEEE / EFMA | ITU-T SG15/ FSAN |
ITU-T G.983.1 | ITU-T G.983.x (x = 2-5) | IEEE 802.3ah, (IEEE 802.3av 10GEPON) | ITU-T G.984.x (x = 1-7) | |
() | 155 /c | 622 /c | 1 /c | 2,488 /c |
155 /c | 155 /c | 1 /c | 1,244 /c | |
, / , / | 155/155 | 155/155 622/155 622/622 | 1000/1000 | 1244/155,622, 2488/622,1244,2488 |
/ , | 1550/1310 | 1550 /1310 (1490/1310) | 1550/1310 (1310/1310) | 1550 /1310 (1490/1310) |
OLT | 64 (128) | |||
, | 20 (60) | |||
, |
PON OLT ONU (. 2). ONU (--), . downstream, EPON ; Ethernet OLT 1:N ONU. ONU , , (. 4).
(OLT -> ), Ethernet OLT ONU 1:N . N 4 64. Ethernet , ( ), PON: OLT ONU - (. 4).
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. 4. OLT ( )
upstream, - , ONU OLT, ONU. , upstream, EPON -. , -, EPON ONU, , . , upstream ( ) ONU , .
, ONU OLT (- /). OLT ONU jam; , PON, 20 , . , .e., . , - . , , , .
. 10. OLT
ONU ONU . Ethernet. ONU , . , ONU , Ethernet (10/100/1000/10000 /). , , 10- . , TDMA(Time-Division Multiple Access), , ONU ( ). , , , QoS (Quality of Service) ..
, ONU , . - , , . ONU, , , , . ONU, , (, ) ONU , OLT ONU. , . , : ONU. PON; , . , (a) , (b) . , PON -.
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, OLT ONU (downstream ) ONU OLT (upstream ). PON. , OLT , .
, OLT, , OLT , ONU. . OLT , ONU. , Grant Request. (Requests) ONU, ONU, , . OLT ONU. ONU Grant.
, OLT , ; ONU - . ONU , .
:
1. http://electronicdesign.com/what-s-difference-between/what-s-difference-between-epon-and-gpon-optical-fiber-networks
2. http://en.wikipedia.org/wiki/Passive_optical_network
3. http://www.skomplekt.com/tovar/1/0/pon/
4. http://book.itep.ru/4/41/pon.htm
5. http://ic-line.ua/wiki/pon-glava1