ISDN

1
ISDN
2
ISDNIntegrated Services Digital Network

• ????? ??????? ??????? ?????????
• ????? ??????? ???? ?? ???? ????? ????? ??? ???
  ????? ????? ???? ???? (???, ????, Data,...)
• ???? ??????? ??? 1984 ??? ????? CCITT ?????
  ?????? standards ???? ?????? I (I series) ?? (I
  100?I 400)
• ?? ????? ?????? ???? ?????? ??? 1988 ?? (I 500, I
  600)

3
I series
?? ?? ????? (??? I 400 ?? I 500 ?? ...) ?? ??????
?? ???????? ???? ????? ????? ??? (??? ????? ????
??? ????? I 451)
???? ??? ???????? ???????? ??? I ?? Q, ?????? I
451 ?? ???? Q 931
4
Basic Rate ISDN

• 3 ????? ??????
• ????? B ???? 64 Kb/s ??? ????? (B channel) ???
  ?????? ?? Bearer (??????)
• ???? D ???? 16 Kb/s ?? 64 Kb/s (D channel) ???
  ?????? ?? Delta
• ???? ???? Basic Rate ????? ?? 2BD

5
???????? B

• ???? ??? ???? ????? ??????? ??? ?? ?? ???????? B
• ???? ????? ??????? ???? ????? voice ?????
  ???????? data
• ??? ???? ????? ?? ???????? ???? ?????? ??? ????
  ???? 128 Kb/s

6
?????? D

• ?????? ?????? ????????? B
• Call setup ????? ?????
• Ringing ????? ???? ??????
• Status indication ????? ??????
• ???? ??????? ??? ?????? ???? ?????? data (????
  voice) ???? ????? ?????
• ?????????? ???????? ?? ??????D ?? ???????? ??
  ???? Data Link ????? ?? LAPD (Link Access
  Protocol, D-channel)

7
??????? ?? ?????????? LAPD

• ???? ??? 8 ????? ?????? ??? ?? ISDN
• ???? ??? ???? ?? ??? ??????? LAPD ?????? ???
  ???????
• ???? ??? ????? ?????? ?? (TEI)Terminal Endpoint
  Identifier
• ????? TEI ?????? ?????? ???????
• ???? ??? ???? ??? ?? ??? ??????? LAPD
  ????(SAPI)Service Access Point Identifier
• ?????? ?????? ?????????? ??????? ?? ?????? ??????
  ????? ?????? ?????????? LAPD (????? X25 ?? frame
  relay)
• ????? (SAPI, TEI) ?? ??? ???? ??? ?? ISDN
  ???????? ??? ???? ?????? ?? ???? D-channel ???
  ??? ??????? ???????

8
???????Encoding

• ??? ??????? ??????? ???????
• ???? ??? ??????? ?? 2B1Q
• ???? ???????? ?????? "bits" ?????? ????? ????
  ???? "quat

9
???? ??? ???????Encoding

• E (69)10 (01 00 01 01)2

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??????? ??? ISDN (ISDN Equipments)

• TE1 Terminal Equipment type 1 ?? ???? ???? ?????
  ?? ???? ??? ISDN
• NT1 Network Termination 1 ?? ???? ???? ??
  ??????? AMI ??? ??????? 2B1Q ??????? ??? ???? TE1
  ???? ??? ISDN

11
??????? ??? ISDN (ISDN Equipments)
??? ??? standard ???? ?????? reference points
?? V ????? ?????? ??? ??????U connector
(??????) ?switch ????? ??????? ??? ?? 2B1Q U
????? ?????? ??? ?????? (??????) ? NT1 ?????
??????? ??? ?? 2B1Q S/T ????? ?????? ??? NT1 ?
TE1 ????? ??????? ??? ?? AMI
12
??????? ??? ISDN (ISDN Equipments)
???? ?? ???? ????? ???? ?????? TE2 ????? ???? ??
???? ?? ???? TA (Terminal Adaptor) ???? ?????
??????? ??? ????? ????? ?? ???? ?????? ??? NT1
??? ?????? ??????? ?? ISDN

• ??????? ????? ????? ??
• ?????? (???? ?? TA ?? NT1)
• ???? ?? ?????? ?? ISDN (???? ?? NT1)
• ???? ??????? ?? ISDN (???? ?????? ??? ???? ?????
  ????? S/T)