ISDN C. Rigault (ENST) Claude.rigault@enst.fr ISDN 1
ISDN 2
Content ISDN conditions Channels and interfaces The S interface ISDN services Tele-services Bearer services Digital Releases ISDN 3
ISDN conditions The Digital UNI : ISDN ISDN ISDN 4
ISDN conditions Digitizing the subscriber loop, why? Several services simultaneously Good quality data transmission (no modem) Have a data transmission billed on volume rather than on time Enjoy new services et supplementary services ISDN 5
ISDN conditions A technological challenge : the 4 ISDN requirements Network Isochronization Digital Connexity Common Channel signaling Connexity Achievement of a full duplex digital transmission on 2 leads (Local echo cancellation) ISDN 6
ISDN conditions Digital connexity No analog islands ISDN 7
ISDN conditions The isochronization requirement Horloge de référence au césium. USRN: Unité de synchronisation du réseau numérique CTP : Centre de transit primaire. USRN CTS : Centre de transit secondaire. USRN USRN CAA : Centre d'abonnés PABX URA URA : Unité de raccordement ISDN 8
ISDN conditions Common channel signaling requirement ISDN 9
Channels and interfaces The ISDN Channels Connection oriented channels (circuit) (billing by time) B : 64 Kbit/s H : Connectionless Channels (packet) D : 16 or 64 Kbit/s UNFORTUNALY, the D Channel for the Basic rate interface only provides 16 Kbit/s ISDN 10
Channels and interfaces The ISDN interfaces The BASIC RA INRFACE (BRI) : 2B+D 2 64 Kbit/s + 16 Kbit/s = 144 Kbit/s The PRIMARY RA INRFACE (PRI) : 30B+D 30 64 Kbit/s + 64 Kbit/s = 1984 Kbit/s ISDN 11
Channels and interfaces Functional groups and reference points S T U V (TNR) (TC) 1 NT1 LT ET 1 (TNA) NT2 (TNR) NT1 1 TA R Domaine de l'usager Domaine de l'opérateur 2 ISDN 12
Channels and interfaces The Basic Rate Interface : BRI S U V 144 Kbit/s utiles (TC) TNR LT ET 2 fils, annulation d'écho ISDN 13
Channels and interfaces The Primary Rate Interface : PRI S T 1984 Kbit/s utiles V (TC) TNA TNR LT ET 4 fils, MIC ISDN 14
Channels and interfaces S interface : The passive S Bus S TNR 144 Kbit/s utiles 150 m ISDN 15
Channels and interfaces S interface : The point to point configuration S TNR 1500 m ISDN 16
Channels and interfaces S interface : characteristics 8 wire Interface, RJ 45 connector MAMI line code Physical Multiplexing 2B+D by 4000 48 bit frames/s Multiple access CSMA/CR for the D channel LAP D data link control procedure on the D channel Signaling in the bloc mode or in the stimulus mode ISDN 17
Channels and interfaces S interface : NT1 functions Echo cancellation DSP + - + - ISDN 18
S interface : line code Clock Données 1 0 1 0 0 1 1 0 Signal ISDN 19
Level 1 : channel multiplexing D0 D1 D2 D3 B1 B2 B1 B2 B1 B2 B1 B2 D0 D1 D2 D3 t 48 bits in 250 µs ISDN 20
Channel multiplexing 1 2 10 11 12 1314 15 23 24 25 26 34 35 36 37 45 F L B1 E D0 A Fa N B2 E D1 S B1 E D2 S B2 46 47 48 E D3 L TNR 48 47 46 45 37 36 35 34 26 25 24 23 15 14 13 12 11 10 2 1 L D3 L B2 L D2 L B1 L D1 L B2 L Fa L D0 L B1 L F ISDN 21
Level 1 : CSMA-CR D0 E0 D1 E1 D2 E2 D3 E3 B1 B1 B1 B1 B1 B2 B1 B2 D0 D1 D2 D3 t Terminal 5 Terminal 1 Code écho 1 0 1 0 0 1 0 0 1 ISDN 22
Level 2 : LAP D frames FANION D'OUVERTURE ADRESSE: DLCI CONTROLE INFOS FCS : FRAME CHECK SEQUENCE FANION DE FERMETURE ISDN 23
DLCI : SAPI and I 8 7 6 5 4 3 2 1 SAPI C/R EA 0 octet 2 I EA 1 3 T1161620-94 EA C/R SAPI I élément binaire d'extension du champ d'adresse élément binaire de commande/réponse identificateur de point d'accès au service identificateur de point d'extrémité de terminal ISDN 24
Level 3 : Q931 signaling PROTOCOLE REFERENCE D'APPEL TYPE DE MESSAGE ELEMENT... D'INFORMATION ELEMENT D'INFORMATION 1 OCT 2 OCTS 1 OCT 1 N ISDN 25
Q931: information element IDENTIFICAUR DE L'EI LONGUEUR DE L'EI CHAMP D'INFORMATION DE L'EI 1 OCT 1 OCT N OCTS ISDN 26
Q931: information flows O OLEX TLEX T SET UP CALL PROCEED IAM SET UP CALL PROCEED ALERT CONNECT CONN-ACK ACM ANM ALERT CONNECT CONN-ACK DISCONNECT MEDIA REL REL REL RLC RLC UNI NNI ISDN UNI 27 USER PAYLOAD
tele-services ISDN Services GLOBAL SERVICE tele-service Negociation of the bearer service Bearer 1 Bearer 2 ISDN 28
tele-services tele-service A telecommunication service is a service that require the transfer of signals A tele-service is defined by ITU (Q9) as a telecommunication service encompasses all the aspects of the communication, including the functions of the terminals, in compliance to protocols ISDN 29
tele-services Tele-service (examples) Telephony 4 Khz or 7 Khz telecopy 64 Kb/s groupe 4. Tele-action 16 Kb/s. Visio-phony 128 Kb/s. Tele-conference 384 Kb/s. photographic videotex. Audio-videotex 64 Kb/s. teletex 16 Kb/s ou 64 Kb/s. ISDN 30
tele-services Tele-service and Bearer service The tele-service is considered as being executable over a variety of Bearer services. Tele-service Global service Bearer service ISDN 31
tele-services Tele-service Classification Interactive Services Conversational Services telephony, visiophony, transactional data transmission Messaging Services Email, voice mail, multimedia mail Information Services Broadcast Services Without user control (TV, radio) With user control (video on demand) ISDN 32
tele-services QOS of the various tele-services Interactive Services Conversational Services telephony, visio-phony, transactional data transmission: small transfer delay Messaging Services Email, voice mail, multimedia mail : unspecified transfer delay Information Services Broadcast Services Without user control (TV, radio With user control (video on demand) ISDN 33
Bearer Services Bearer Service A network provides a Bearer service when the signals delivered at the destination point are the same as those at the source point The Quality of Service determines the parameters of the Bearer service One of the most essential parameters is the end to end transfer delay. ISDN 34
Bearer Services Bearer Services (examples) 64 Kb/s, transparent switched : CCBT 64 Kb/s, non transparent switched CCBNT 64 Kb/s, connectionless. packets, 64 Kb/s, B channel packets, 16 Kb/s, D channel ISDN 35