Petrozavodsk State University, Alex Moschevikin, 2004

1
Asynchronous Transfer Mode

• ?????????? ?? ?????? ??????
• Internetworking Technology Handbook (Cisco
  Systems)
• ?.????. ?????????? ???????? ??????.
• http//www.citforum.ru/nets/articles/atm_base.shtm
  l (?. ????????. ?????? ?????????? ???)
• http//www.citforum.ru/nets/articles/atm_2_000.sht
  ml (?. ????????. ???????? ??????? ??????????)
• FDDI Technology Guide (Cabletron Systems)
• ?.??????, ?.??????. ???????????? ??????????
  ???????????? ?????

Rev. 1.01 / 06.02.2005
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
2
??????????? ATM

• Asynchronous Transfer Mode - ???????? ??????????
  ? ??????????? ??????, ?????? ??? ??????????
  ?????? ? CCITT ? 1988 ????, ?????? ????????
  ??????????? ? 1992 ????
• ?????????? ? ????????? ?????? ?????? OSI/RM
• ???????? ?????????? ?????????? ???? (??????,
  ????, ?????, ??.) ?????????? ???????? (? ???????
  53 ?????, cells) ?? ??????????????????
  ???????????? ??????
• ????? ???????? ? ????????, ???????????
• ???????? ???????? - ??????? ?? ???????????
  ??????, ?????? ????? 155????/? (?? ??????????
  ??????????)
• ??????????? ??????????? ? ???? ??? ???????
  ???????, ???????????????, ????????? ????????
  ???????? (????????, E1)
• ??? ????????? ? ???? ????? ?????????? ???????
  (??????????????? ?????????? ???????????) ?
  ??????????? ??????? (?????? ?????????? ????????),
  ????? ??????????? ????????????? ??????
  ???????????, ??? ? ?????? ?????????? ????? TDMA
• ????????? ?????? ??????? ?????? ???????? ?
  ???????? ?????? ??????????

Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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????????? ???? ATM
ATM ???? ??????? ?? ???????????? ??? ? ?????????
?????????, ??????????? ???? ? ??????. ??????????
??????????? ????????? ???????????? ????? ??????,
???????? ?????????? ??????????, ????????? ?? ??
???? ?? ????? ????????? ??????. ????????? ???
???? ??????????? ??? UNI (user to network
interface) ? NNI (network to network interface).
???? ???
UNI
UNI
NNI
NNI
UNI
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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????? (??????) ATM
???? UNI
GFC VPI VCI PT CLP HEC Data (48 ????)
???? NNI
VPI VCI PT CLP HEC Data (48 ????)
General Flow Control - 4 ????, ????? ??
????????????, ???????? ?????????? ? ??????
?????????? ?? ????? ??? ??????????, ??????????? ?
NNI. Virtual Path Identifier - 1 (1.5) ???? (4096
????? ? ???????? ?????? ???????????). Virtual
Channel Identifier - (2 ?????). ???? ???????? VPI
? VCI ???????????? ????????????? ???
??????????????? ?????. Payload Type - ??? ??????
(3 ???? ??????????/??????, ??????????, ???????
????????? ?????? ? ????? AAL5. Cell Loss Priority
- 1 ??? ?????????? ??????????? ??????. Head Error
Check - ??????????? ????? ????????? (1 ????).
???? ?????? ?? ??????????? ?? ????????????
????????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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????????? ? ????? ??????
?????????? ????? ????? ???????????? ??? ?????
???? ?? ??????????? ???????????? ?????? ??? ??
?????????????? ??. ? ???????? ??? ??? ??????????
?????????? ???? ?????-????? (???? ?
???????????????), ?? ?????? ? ????-??-??????
(????????????????), ????? ?????? ?? ???????????
????????????????? ????? ????? ?? ????
??????????. ?? ?????? ???????????? ??????????
?????????? ??? ?????????? ?????? ????????
????????? NSAP (Network Service Access Point)
(???????? ?.164, 20-??????? ??????). ?????
?????????? 3 ???? ??????? ???, ?????? ????
?????????????? ?? ???. ????????? 13 ???? ??????
?????????????? ??????????, ?????????? -
??????????, ? ???? ????????????. ??? ?????????
????? ????? ???????? ?????? ?????? OSI/RM,
????????, ????????-????????????? ??? TCP/IP, ?
????? ??? ????????????? ????????????????
?????????? ???????????? ??? ??????? ? ???????????
???????? (ARP-, DNS-???????? ??????).
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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???????? ???????????? ???
VPI/VCI?
VPI/VCI?
VPI/VCID
?
?
VPI/VCI?
???????????
?? ????? ???????????? ?????????? ???
????????????? ??? ?????????? ??????????? ? ????
??????? ?????????? ??????? ??????????????? ?????
?? ????????? ?????????? ???????? VPI/VCI. ?
???????? ?????? ?? ???????? ? B ????????
(????????????? ?????), ????? ??????? ??????????
??????????? ????? ?????? ????????????
(??????????????? ????????????? ??????????? ?????
?? ????? ???????? ??????). ??? ???? ? ??????????
???? ???????? VCI/VPI, ? ????? ??? ?????????
???????? ???????????, ????? ?????????????? ??????
?? ?????-?? ???? ????, ??????????? ?? ?????
??????????? ?????????? ???????????? ????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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???? ???
??????????
????????? ????? ??????? ???????
??????????.
?????????
????????????
ATM Adaptation Level
???????
?????????? ATM
?????????
?????????? ???????
??????????
OSI/RM
???
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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?????????? ??????? ???
?????????? ??????? ??? ??????? ?? ??? ????????? -
Transmission Convergence (?????????? ?????????? ?
????????) ? PMD (????????? ?? ?????
????????). ?? - ????????????? ?????? ?????
(??????????? ?????????, ?????? ?????? ?????? 53
?????, ???? ????? ?????????? ?????? ?????
????????? - ??????, ??????? ?????? ?????????
???????????), - ?????? ? ???????? ???????????
????? ????????? (HEC), - ????????? ??????????????
???????? Idle (??? ????????????? ????? ???????
??????), - ???????? ?????? ??? ? ?????? ?????
??????? ???? (????????, SONET/SDH, DS-3 ??? 155
????/? ? ??????????? 8?/10? ??? ??????????????
????? ????). PMD - ???????????? ?????????????
???????????? ???????, - ????????????? ???????????
????????????? ??????? (? ??? ????? ???????????)
??? ???????????? ????, ???????????? ? ????????
????? ????????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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????????? ??????? ???
?? ????????? ?????? ??? ????????? ?????? ??????,
? ????? ?? (???????) ???????????? ?? ???????
?????? ??????????? ?????? ?? ?????????
???????????. ?? ????????? ?????? ??????????
????????? ??????????????? ????? ?? ????? ? ????
???????????. ?????? ? ??????? ????????? ATM ???
?????????????? ?????? ??? ???????? ? 48 ????????
??????. ??????? AAL ????????? ?? ????? ???????
??????? ??????????? ?????????????? ?????? ???,
???????????? ???? ?????? ?????????????
????????. ?????????? 4 ???? ?????,
??????????????? ??????? ????????? ???, ???????
????????? ????????????? ????????? ????????
???????????? (Quality of Service, QoS). ???????
QoS ???????? ??? ?????????? ???????
???????????????? ????? ??????? (?? ?????????
???????????? ???? ???????, ???????????? ??? ???,
?? ???????????, ???????????? ? ????? SONET/SDH
??? ISDN).
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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???????? ???????????? QoS
????? ? ? ? D
?????? ????????? ??????? ???????????? ???????????? ?? ???????????? ?? ????????????
???????? ???????? ?????? ?????????? ?????????? ?????????? ??????????
?????? ?????? ??????? ????????????? ?? ?????????? ????????????? ?? ?????????? ????????????? ?? ?????????? ?? ????????. ?? ??????????
??????? ????????? ??? AAL 1 AAL 2 AAL 3/4, AAL 5 AAL 3/4
????? ?????????? ??????? ? ???? ??????????
????????? ??????? ????????? ??? ? ???????????? ?
????????? ??????? ????????????. ????????? ??????
??????? ????????? ?????????? ???? ?? ?????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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ATM Adaptation Level
AAL 1 1 ???? ?????????? (?????????? ??????
??????????????? ???????????? ?????) 47 ????
??????. AAL 1 ?????????? ??? ????????? ??????????
???????? ???????? ????? (??????????
????-????). AAL 2 ?????????? ??????????
???????? ?????? ? ?????????? ????????? ? ????????
??????? (?????? ?????? ?? ??????????,
???????????? ?????????????????). ????????
???????? - 45 ??????, 3 ????? - CRC ????? ????
?????? ?????????? ??????. AAL 3/4 ????????
?????????? ? ?????????? ????????? ??? ?
??????????????? ?? ??????????, ??? ? ?? ?
??????????????? ?? ?????????? ?????? ??????
???????. ?????? - 44 ????? (?? 53). ????? ?????
AAL 2 ???? ??? ??? ?????????? ? ?????????????
??????????????????? (??? ????????????? ??????????
??????????? ???????). ????? ????? ?????????
????????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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AAL 5
AAL 5 ???????????? ???????????? ?????????????
???????? ?? ???? ??? ??????? ??????. ????????
?????????? ???????? ??? ?????? ??? ?????? ??????
??????????. ???????? ?????????? (??????? ??????
???????? ?????? ??????? ?? ?????? ?? 48 ????)
?????????? ? ?????? ??????, ????? ?????????. ?
????????????? ? ?????? ?????????? ?????????
??????? ???????, ? ? ????????? - ?????????
??????????. ????????? ????????? ?????? CRC-32,
????? ???????? (0-65535), ??????? ???????? ?????
(??? ????????? ??????), ???? ?????????? ?????? ??
???????? 48 ??????. ????? ????????????????
?????? ?????????, ? ??? ???? ??????? "????????
???????" ? "?????????? ????????". ??? ?????????
?????????????? ?? ????? ??????????? ??????? ?
????. "???????? ???????" ????????????? ???????,
??????? ?????????? ???????????, ???????????
???????????????? ?????????? ??????? ?? ??????? ?
??. "?????????? ????????" ??????????? ??
????????? ?????????-??????????? ???????? ?
??????? ????????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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LAN Emulation
???? ???
NNI
UNI
LANE - ???????? ????????? ??????????????
????. ??? ???????????? ?????? ??? ????? ?????
???, ??? ????????? ? ???????? ?????????? ????,
???????????? ????? ??? (????????, Ethernet) ?
?????? ????? ???. ?????? ?? ??????????????
??????? ??? ? ?????? ??? ????????? ???????????
???-LAN ?????????? (???????????). ? ??? ????
??????????? ??? ????? ? ?????????? ? ???? MAC
??????? ? ???, ????? ????? ???? ???????
???????????? MAC ??????? ???????????? ????
??????? ATM-LAN ????????????, ???? ?????, ??????
??????????? ???????? ????? ??? ???????? ???).
??????????? ???????????? ???? ??
????????????????? ?????????, ? ??????????? ?? 48
????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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LAN Emulation
??????????? ?????????? ????? ???????????? ??? -
?? ???? ?????? ????????. ?????????? ?????
?????????????? ????????????????? ?????? ?
????????? ??? ????????? ????????????? ????????
??? ???, ????????, Ethernet. ? ??? (!) ???
????????????????? ?????????, ??. ????? ?????-??
??????? ???????????? ?????????? ???????? ???????
????????????. ??? ???????? ???? ??????? ?? ??????
???????????, ???? ?????? ????. ?????? LES (LAN
Emulation Server) ?????? ??? ????, ???????
??????????? ???? ???????????? MAC ??????? ???????
???????????? ????? ??????? ????????? (??????
?????????? ?????? ??????????, ????????? ???
????????? ?? ????? ?????? ???? ??? ????? - ?????
?????? ???????).ARP ??????? (??? ????? IP
??????????, ?????????? MAC ?????? ?? ????????
??????) ????????? ?? ????? ??????. ???? ?????? ?
???? ?? ??????? ?????? - ???????? ????
??????????? ????????????. ?????????
????????????????? ????????? ??? ????? ????????
????????? ???????. ?????? ??? ???? ??????
Broadcast and Unknown Server, BUS. ????? ?????
??? ??????? ?????????? ???????? ???????? LES ?
???? ??????? ???? ??????? ????????????????? ?????
??? ????? ? ??????????? ???????, ?? ???????? ?
????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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LAN Emulation
??????????? ????? ???????? LES ? BUS (?? ??????
??? ?????? ????) ???? ??????????? ??????? ??
?????? ????? ??? ???? ????????? ??????????
??????????? ???. ?????? ??? ???? ?????? LAN
Emulation Configuration Server, LECS. ???? ??????
?????? ?????? ???? ??????????? ?????, ? ?????
???????? ?? ???????? ?????????? - ???-??????
???????? LES ? BUS ?????? ????, ??? ????
(????????, Ethernet ??? Token Ring), ????????????
?????? ?????, ??????????????? ???? ????? ?
?.?. ???????? LANE ??????? ??????? ?????? ??
?????????? ???????, ????????????? ??????????????
? ????????????, ???????????? ??????? ?????????
??????? (????? 5 ???? ?? 53).
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs
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Multiprotocol over ATM (MPOA)
???? ???? ??? ???????????? ?????????? MPOA, ??
???????? ?????????? ?????? ??????? ?????
?????????? ??????? (??????????????) ?????????
?????. ?????? ????????? ?????? ????? ?????? ??
???????? ????, ????? ???? ????????? MPOA ????????
???????? ??????? ????? ??? ??????? (??. ???????)
??????????????, ???????? ??? ????? ?? ?????????.
Petrozavodsk State University, Alex Moschevikin,
2004
NETS and OSs