Transcript Lecture2 - GUNET eClass

Universal
Mobile Telecommunication System
(UMTS)
Περιεχόμενα
1. Εισαγωγή
2. UTRAN
3. Mobility
4. QoS
5. IMS
6. OSA
7. MEXE
2
Εισαγωγή στο UMTS
3
Εισαγωγή στο UMTS
4
Χαρακτηριστικά του UMTS
•Κοινή παγκόσμια χρήση
•Υποστήριξη όλων των εφαρμογών
•Υποστήριξη PS (Packet Switched) & CS (Circuit Switch)
•Ρυθμοί μετάδοσης μέχρι 2Mbps (κινητικότητα - ταχύτητα)
WCDMA (Wideband Code Division Multiple Access)
•384 Kbps wide area coverage
•2 Mbps local area coverage
•10 ms frame length
•Chip rate = 3.84 Mchips/s
•FDD (Frequency Division Duplex)
Uplink 1920-1980MHz;Downlink 2110-2170MHz
Uplink 1850-1910MHz;Downlink 1930-1990MHz
•TDD (Time Division Duplex)
5
Διαδικασίες προτυποποίησης UMTS
IMT 2000 (ITU): International Mobile Telecommunications
2000: initial trial systems & 2000MHz
•17 διαφορετικές προτάσεις κατατέθηκαν στην ITU το 1998
•11 terrestrial & 6 Mobile satellite systems
•Αξιολόγηση των προτάσεων (τέλος του 1998)
•Διαπραγματεύσεις για συνένωση τους (6/1999)
•Προδιαγραφές για την ραδιο-τεχνολογία μετάδοσης (τέλος του 1999)
•Πιο σημαντικές προτάσεις:
•UMTS (W-CDMA): μετεξέλιξη του GSM
•CDMA2000: Ενδιάμεσο πρότυπο για το IS-95
•TD-CDMA (Time Division synchronous CDMA): UWC-136/EDGE για την επαύξηση
των δυνατοτήτων των D-AMPS και GSM
6
3GPP
Third Generation Partnership Project
•ETSI (Ευρώπη),
•Association of Radio Industries and Business Telecommunication
Technology Committee (ARIB/TTC - Ιαπωνία),
•American National Standards Institute (ANSI - Αμερική),
Telecommunication Technology Association (Ν. Κορέα),
•Chinese Wireless Telecommunication Standard (CWTS).
Εκδόσεις:
Release 99 (12/1999): Μετεξέλιξη του GSM δικτύου
Release 2000: Μετεξελίξεις για το IS-95 και το EDGE; δυνατότητα
σύνδεσης με άλλα δίκτυα πρόσβασης (WLAN,BRAN)
7
Release 99
•UTRAN: UMTS Terrestrial Radio Access Network
•W-CDMA Ραδιοεπαφή
•Υποστήριξη Time Division Duplex & Frequency Division Duplex
•TDD: Micro & Pico κυψέλες καθώς και ασύρματες εφαρμογές
•FDD: Wide-area coverage (public & macro κυψέλες)
•MC (Multicarrier) mode: εγκαθίδρυση συμβατότητας ανάμεσα σε UMTS
και CDMA 2000
8
Λογική αρχιτεκτονική UMTS
SMS-GMSC
SMS-IWMSC
SM-SC
E
C
Circuit Switched domain
Gd
MSC/VLR
HLR
D
Ge
Gs
A
Iu
R
Uu
Iu
UMTS Access
TE
MT
UTRAN
Network
Gr
SGSN
GSM
Network
TEAccess
MT
BSS
R
Um
Gn
Gc
Gi
PDN
GGSN
Gn
Gb
SGSN
CAMEL
GSM-SCF
Ga
Ga
Gp
GGSN
Packet Switched domain
Other PLMN
CGF
Gf
TE
Billing
System
EIR
Signalling Interface
Signalling and Data Transfer Interface
9
UTRAN (TS 25.401)
Core Network
Iu
Iu
RNS
RNS
Iur
RNC
Iub
Node B
RNC- BSC
Node B - BTS
RNC
Iub
Iub
Node B
Node B
Iub
Node B
Iu, Iub, Iur:ATM transmission principles
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Γενική αρχιτεκτονική πρωτοκόλλων
Non-Access Stratum
Radio
protocols
Radio
protocols
UE
Radio
(Uu)
Iu
Iu
proto
cols
proto
cols
Access Stratum
UTRAN
Iu
CN
User Plane
The radio access bearer service is offered from SAP to SAP by the Access Stratum.
Uu and Iu interfaces linked together provide this radio access bearer service.
11
Γενική αρχιτεκτονική πρωτοκόλλων
CM,MM,GMM,SM
Non-Access Stratum
Radio
protocols
Radio
protocols
UE
Radio
(Uu)
CM,MM,GMM,SM
Iu
Iu
proto
cols
proto
cols
Access Stratum
UTRAN
Iu
CN
Control Plane
Note: CM, MM, GMM and SM exemplifies a set of NAS control protocols between UE and
CN. There may be different NAS protocol stacks in parallel.
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Serving & Drift RNC
Core Network
Iu
DRNS
Iur
SRNS
Cells
UE
RNC:
SRNC:
DRNC:
•Admission
•RR Allocation
•Congestion Control
•Handover
•Macro-diversity
•RR Allocation
•Αυτόνομη διαχείριση των ράδιο πόρων του UTRAN
•O&M Διεπαφή
•ATM switching & multiplexing
•Συνολικός ελεγχος του RNS
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Node B
•Η φυσική μονάδα για μεταδόσεις δεδομένων στη ραδιο-επαφή
•Ελέγχει μία ή περισσότερες κυψέλες
•Μπορεί να υποστηρίζει FDD & TDD
•Αποτελεί σημείο τερματισμού του ΑΤΜ
•Εκτελεί:
 Rate adaptation
 Forward Error Correction (FEC)
 Quadrature Phase Shift Keying (QPSK)
 Μετρήσεις στην ισχύ και την ποιότητα της σύνδεσης
(Μεταφορά στοιχείων στο RNC για εκτέλεση
handover/macro-diversity)
 Power Control
W-CDMA spreading/despreading
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UMTS User Equipment
UMTS UE = Mobile Equipment & UMTS SIM - USIM
UMTS UE - Node B:
FEC
Power Control
Radio Measurements
Modulation - Demodulation
W-CDMA Spreading/Despreading
UMTS UE - RNC:
Radio Resource Control
Handover (CS) & Cell Selection (PS)
Ciphering/De-ciphering
UMTS UE - Core Network:
Mobility Management(Location Registration/update, Attach-Detach)
Session Management (PDP Context De/Activation)
Service Request
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Γενικό Μοντέλο
Radio
Network
Layer
Transport
Network
Layer
Control Plane
User Plane
Application
Protocol
Data
Stream(s)
Transport Network
User Plane
Transport Network
Control Plane
Transport Network
User Plane
ALCAP(s)
Signalling
Bearer(s)
Signalling
Bearer(s)
Data
Bearer(s)
Physical Layer
General protocol model for UTRAN Interfaces. The structure is based on the
principle that the layers and planes are logically independent of each other.
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Application Protocols
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Radio Access Network Application Part - RANAP
TS 25.413
•Radio Access Bearer Management (setup, maintenance, release)
•Management of the Iu connections
•Transport of non-access stratum info between UE-CN
(mobility management signaling, broadcast information)
•Exchange UE location information between RNC and CN
•Paging requests from CN to UE
•Overload and general error situation handling
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Radio Network Sublayer Application Part - RNSAP TS
25.423
•Management of Radio Links
•Paging
•SRNC relocation
•Measurements of dedicated resources
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Node B Application Part - NBAP
TS 25.433
•Management of common channels, radio resources and radio links
•Configuration management
•Measurement handling and control
•Synchronization (TDD)
•Reporting of Error situations
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Radio Resource Control - RRC
TS 25.331
•Broadcasting Information
•Management of connections between UE and UTRAN
•Management of radio bearers
•Ciphering Control
•Power Control
•Message Integrity protection
•Paging and notifying
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Transport Network Layer - Layer 3
•Iu, Iur: Signaling Connection Protocol Part (SCCP) [Q.711, Q.716]
Provides connectionless and connection oriented services
•Iu-CS, Iur, Iub: ALCAP [Q.2630.1, Q.2150.1, Q.2150.2]
Signaling needed to setup bearers to transmit data via the user plane.
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PS domain με UTRAN δίκτυο πρόσβασης
GMM/SM
GMM/SM
RRC
RRC
RANAP
RANAP
GTP-C
GTP-C
RLC
RLC
SCCP
SCCP
TCP/UDP
TCP/UDP
MAC
MAC
SIGNAL
SIGNAL
IP
IP
AAL5
AAL5
L2
ATM
ATM
L1
RF
RF
MS
RNS
IP
IP
L2
L2
L2
L1
L1
L1
SGSN
GGSN
HOST
Control Plane
APPL
APPL
TCP/UDP
IP
Relay Function
Relay Function
PDCP
PDCP
GTP-U
RLC
RLC
TCP/UDP
Relay Function
GTP-U
GTP-U
TCP/UDP TCP/UDP
IP
TCP/UDP
IP
IP
GTP-U
TCP/UDP
IP
IP
IP
IP
MAC
MAC
AAL5
AAL5
L2
L2
L2
L2
RF
RF
ATM
ATM
L1
L1
L1
L1
MS
RNS
SGSN
GGSN
HOST
User Plane
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Στοίβα πρωτοκόλλων με UTRAN δίκτυο
πρόσβασης
Applicatio
n
TCP
Applicatio
n
TCP
UDP
IP
UDP
TCP
UDP
IP
IP
Other Network
UMTS Link
GPRS Link
UMTS Radio Link
GPRS Core Network Link
PDCP
PDCP
GTP-U
RLC
RLC
TCP/UDP
GTP-U
GTP-U
TCP/UDP TCP/UDP
GTP-U
IP
TCP/UDP
IP
IP
IP
IP
MAC
MAC
AAL5
AAL5
L2
L2
L2
RF
RF
ATM
ATM
L1
L1
L1
MS
RNS
SGSN
GGSN
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Δρομολόγηση και μεταφορά πακέτων:
Ενθυλάκωση
Ενθυλάκωση
Το τμήμα μεταγωγής πακέτου
μεταφέρει PDP Protocol Data
Units (PDU) ανάμεσα σε
εξωτερικά δίκτυα και ένα MS
με διαφανή τρόπο
 Όλα τα PDP Protocol Data
Units ενθυλακώνονται και
αποθυλακώνονται για την
περαιτέρω δρομολόγησή τους

Λειτουργίες ενθυλάκωσης
Στο δίκτυο κορμού ανάμεσα σε
δύο κόμβους GSN ή ανάμεσα
σε ένα SGSN και ένα RNC
 Μια ανάμεσα στο MS και το
SGSN στην περίπτωση GSM
δικτύου πρόσβασης
 Μια ανάμεσα στο MS και το
RNC στην περίπτωση UMTS
δικτύου πρόσβασης

Δικτυακά στοιχεία
ενθυλάκωσης

MS

RNC
 SGSN
 GGSN
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Δρομολόγηση και μεταφορά πακέτων στο UMTS
Ανάμεσα στο MS και το SGSN

Με το πρωτόκολλο PDCP
Ανάμεσα στο SGSN και το GGSN
Με το πρωτόκολλο GTP χρησιμοποιώντας UDP/IP
 Το GTP tunnel αναγνωρίζεται μοναδικά από ένα Tunnel ID
(TEID) και την διεύθυνση του GSN (SGSN or GGSN)

APPL
APPL
TCP/UDP
IP
Relay Function
Relay Function
PDCP
PDCP
GTP-U
RLC
RLC
TCP/UDP
Relay Function
GTP-U
GTP-U
TCP/UDP TCP/UDP
IP
TCP/UDP
IP
IP
GTP-U
TCP/UDP
IP
IP
IP
IP
MAC
MAC
AAL5
AAL5
L2
L2
L2
L2
RF
RF
ATM
ATM
L1
L1
L1
L1
MS
RNS
SGSN
GGSN
HOST
User Plane
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Υποστήριξη ποιότητας υπηρεσιών στο UMTS
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Μηχανισμοί υποστήριξης ποιότητας υπηρεσίας
• Admission Control:
Περιέχει πληροφορίες για τους υπάρχοντες και παραχωρηθέντες
πόρους του δικτύου, και αποφασίζει αν υπάρχουν αρκετοί πόροι ώστε
να υποστηριχθεί μια καινούργια αίτηση.
Βασικός έλεγχος για ένα PDP Context στο SGSN, ενώ στα GGSN & UTRAN
επιβεβαίωση δυνατότητας υποστήριξης του QoS για το
PDP Context.
•Bearer Service Manager
Συντονισμός σηματοδοσίας για την εγκαθίδρυση, μετατροπή και διατήρηση
Ενός bearer service. Επικοινωνία με τις οντότητες admission & subscription control.
BS-MT: Αιτήσεις για εγκαθίδρυση local bearer service; Μετάφραση UMTS QoS
Χαρακτηριστικών σε αυτά του local bearer service.
BS-SGSN: Αντίστοιχες λειτουργίες για την εγκαθίδρυση RAB,Iu, CN bearers.
Συνεργασία με τις οντότητες στο UTRAN και το GGSN.
BS-GGSN: Αντίστοιχες λειτουργίες για την εγκαθίδρυση CN bearers και τη
διαλειτουργικότητα με τα εξωτερικά δίκτυα
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Μηχανισμοί υποστήριξης ποιότητας υπηρεσίας
•Resource Manager:
Διαχείριση δικτυακών πόρων βάση των χαρακτηριστικών του bearer. Υποστήριξη
QoS με μηχανισμούς scheduling, bandwidth management, power control.
•Traffic Conditioner:
Πιστοποίηση των χαρακτηριστικών μετάδοσης στις προδιαγραφές που έχουν
οριστεί. Εκτέλεση traffic shaping & traffic policing.
TC-MT: uplink
TN-UTRAN & GGSN: downlink
•Packet Classifier:
PC-MT: Εκχώρηση πακέτων από το local BS manager στο κατάλληλο UMTS
bearer (DSCP, Transport layer Port number, security parameter index)
PC-GGSN: Εκχώρηση πακέτων από εξωτερικό BS manager στο κατάλληλο UMTS
bearer.
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Κλάσεις και παράμετροι QoS
Ορισμός κλάσεων βάσει: delay, bit rate, bit error rate, traffic handling
priority requirements
Conversational Class: Fixed resource allocation (like CBR in ATM)
Παράδειγμα:Video telephony
Streaming Class: Tolerance to a certain amount of delay variation
(like VBR in ATM)
Παράδειγμα:Video Downloading
Interactive Class: Services requiring assured response times
(scheduling priority)
Παράδειγμα:E-commerce, Web
Background Class: Best effort services (lowest priority)
Παράδειγμα:file transfer, E-mail
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Κλάσεις και παράμετροι QoS
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PDP Context activation
•Ενεργοποίηση PDP Context με συγκεκριμένα χαρακτηριστικά QoS:
(traffic class, transfer delay, traffic handling priority)
•Πολλαπλά PDP Context μπορούν να μοιράζονται την ίδια IP
διεύθυνση
•Παροχή φίλτρου από το MS για κάθε PDP Context
• GGSN: χρήση φίλτρου για την απο-πολύπλεξη εισερχόμενων
πακέτων στο σωστό PDP Context
• Χαρακτηριστικά φίλτρου:IP source, IP Dest, Port number, DSCP
• Ύπαρξη φίλτρου: MS & GGSN (unidirectional flows)
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PDP Context Activation
1 . Ενεργοποίηση εφαρμογής
2. Έλεγχος ύπαρξης PDP Context με παρόμοια χαρακτηριστικά QoS
3.
I) Πολύπλεξη πακέτων στο υπάρχον PDP Context
II) Εναλλακτικά τροποποίηση υπάρχοντος PDP Context
III) Εναλλακτικά ενεργοποίηση “Secondary PDP Context”
Secondary PDP Context: Κληρονομεί τα περισσότερα
χαρακτηριστικά του “Primary PDP Context”. Εγκαθίδρυση νέου
bearer (GTP Tunnel).
Default PDP Context: Δεν σχετίζεται με συγκεκριμένη ροή πακέτων,
και επιτρέπει τη μεταφορά πακέτων που δεν «ταιριάζουν» σε κάποιο
από τα υπάρχοντα PDP Context να φτάσουν στο MS
33
Core Network QoS
UMTS Packet Core Network = IP Network
Δυνατότητες υποστήριξης QoS:
1) Χωρίς κάποια επιπλέον υποστήριξη (το δίκτυο κορμού
δεν αποτελεί bottleneck)
2) ΑΤΜ based transport (εμπεριέχει μηχανισμούς
υποστήριξης QoS)
3) Differentiated Services (marking points: RNC uplink &
GGSN downlink)
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Χρέωση - Ορισμοί
Charging is the function whereby information related to a chargeable event is
formatted and transferred in order to make it possible to determine usage for which
the subscriber may be billed.
Billing is the function whereby CDRs generated by the charging function are
transformed into bills requiring payment.
Accounting is the process of apportioning charges between the roles in the UMTS role
model.
Charging Detail Record (CDR) is a formatted collection of information about a
chargeable event (e.g. timestamp of call setup, duration of the call, timestamp of PDP
context activation, amount of data transferred, etc) for use in billing and accounting
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Χρέωση - Λογική Αρχιτεκτονική
Data Network
(Internet)
CGF: Distributed functionality in SGSN & GGSN
or Centralized Network Element
Inter-PLMN
Network
Gp
Gi
PS Domain
GGSN
G-CDR
CDR
Ga
Gn
CDR
CGF
SCF
Ga
CAP
CDR
M-CDR
S-CDR
S-SMO-CDR
S-SMT-CDR
SGSN
IuPS
Gb
RNS
BSS
BSC
BTS
Billing
System
RNC
BTS
Node B
Um
Node B
Uu
MS
36
Αρχές διαδικασιών χρέωσης
•Σε κάθε PDP Context εκχωρείται ένας μοναδικός προσδιοριστής για τη λειτουργία των
διαδικασιών χρέωσης (charging ID)
•Οι μετρήσεις του όγκου δεδομένων που ανταλλάσσονται γίνονται ξεχωριστά για το uplink
και το downlink
•Οι μηχανισμοί χρέωσης θα παρέχουν τη διάρκεια ενός PDP Context με πληροφορίες όπως
ημέρα και ώρα
• Τα GSNs θα μπορούν να χειρίζονται χαρακτηριστικά χρέωσης που θα προμηθεύονται από
τις πληροφορίες συνδρομής που βρίσκονται αποθηκευμένες στην HLR
• Τα SGSNs θα υποστηρίζουν τη χρέωση υπηρεσιών CAMEL
37
Συλλογή πληροφοριών χρέωσης
• Χρήση πόρων στη ραδιο-επαφή: amount of data uplink, downlink, QoS
• Διάρκεια χρήσης: Activation - Deactivation of PDP Context
• Χρήση γενικών πόρων του δικτύου GPRS & διαδικασιών διαχείρισης (π.χ.,
mobility management)
• Προορισμός και πηγή: Ο προορισμός καθορίζεται με την ακρίβεια του APN
•Χρήση εξωτερικών δικτύων: Δεδομένα που ανταλλάσσονται με εξωτερικά δίκτυα
•Τοποθεσία του κινητού: HPLMN, VPLMN, πληροφορίες τοποθεσίας μεγαλύτερης
ακρίβειας (από τις διευθύνσεις SGSN, GGSN)
• SGSN: Συγκεντρώνει πληροφορίες για τη χρήση των ράδιο-πόρων
• GGSN: Συγκεντρώνει πληροφορίες για την επικοινωνία με εξωτερικά δίκτυα
38
Αρχές συλλογής δεδομένων χρέωσης
• Κάθε PDP Context δημιουργεί τα δικά του records
(S-CDR <--> SGSN, G-CDR <--> GGSN
• Ένα SGSN μπορεί να στείλει προαιρετικά records σχετικά με τη
διαχείριση κινητικότητας (M-CDR)
• To MS δημιουργεί records για το SMS
• Η αποστολή των records στο CGF εξαρτάται από διάφορες
παραμέτρους (timer expiration, transferred data volume limit,
routing area update, intra-inter handover)
• Η συσχέτιση των records από το SGSN και το GGSN για το ίδιο
PDP Context γίνεται από το Charging ID
•Το RNC είναι υπεύθυνο να μετράει τον αριθμό δεδομένων που δεν
στάλθηκαν στο κινητό (λόγω προβλήματος στη μετάδοση ή λόγω
εκτέλεσης μεταπομπής)
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S-CDR
Field
Description
Record Type
System Type
Served IMSI
M
C
M
SGSN Address
Routing Area
Charging ID
M
O
M
GGSN Address Used
M
Access Point Name
Network Identifier
PDP Type
Served PDP Address
List of Traffic Data
Volumes
M
Record Opening Time
M
Duration
SGSN Change
Cause for Record Closing
Record Sequence Number
M
C
M
C
Access Point Name
Operator Identifier
RNC Unsent Downlink
Volume
M
M
M
M
C
GPRS SGSN PDP context record.
Indicates 3G-UMTS System; Not present for GSM GPRS.
IMSI of the served party (if Anonymous Access Indicator is FALSE or not
supplied).
The IP address of the current SGSN.
Routing Area at the time of the record creation.
PDP context identifier used to identify this PDP context in different records created
by GSNs
The IP address of the GGSN currently used. The GGSN address is always the same
for an activated PDP.
The logical name of the connected access point to the external packet data network
(network identifier part of APN).
PDP type, i.e. IP
PDP address of the served IMSI, i.e. IPv4 or IPv6
A list of changes in charging conditions for this PDP context, each time stamped.
o categorise traffic volumes, such as per QoS/tariff period. Initial and subsequently
g data values are listed.
Time stamp when PDP context activation is created in this SGSN
or record opening time on following partial records
Duration of this record in the SGSN.
Present if this is first record after SGSN change.
The reason for the release of record from this SGSN.
Partial record sequence number in this SGSN. Only present in case of partial
records.
The Operator Identifier part of the APN.
The downlink data volume which the RNC has not sent to MS.
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G-CDR
Field
Description
Record Type
Served IMSI
M
M
GGSN Address
Charging ID
M
M
SGSN Address
Access Point Name
Network Identifier
PDP Type
Served PDP Address
Dynamic Address Flag
M
M
List of Traffic Data
Volumes
M
Record Opening Time
Duration
Cause for Record Closing
Record Sequence Number
Charging Characteristics
M
M
M
C
C
M
M
C
GPRS GGSN PDP context record.
IMSI of the served party (if Anonymous Access Indicator is FALSE or not
supplied).
The IP address of the GGSN used.
PDP context identifier used to identify this PDP context in different records created
by GSNs
List of SGSN addresses used during this record.
The logical name of the connected access point to the external packet data network
(network identifier part of APN).
PDP type, i.e. IP, PPP, or IHOSS:OSP
PDP address, i.e. IPv4 or IPv6
Indicates whether served PDP address is dynamic, which is allocated during PDP
context activation.
A list of changes in charging conditions for this PDP context, each time stamped.
Charging conditions are used to categorise traffic volumes, such as per tariff period.
Initial and subsequently changed QoS and corresponding data values are listed.
Time stamp when this record was opened.
Duration of this record in the GGSN.
The reason for the release of record from this GGSN.
Partial record sequence number, only present in case of partial records.
The Charging Characteristics flag retrieved from subscriber's data as described in
subclause 6.1.6.5.
41
The IP-Multimedia Subsystem (IMS)
GSM
Phase 1
UMTS
Phase 2 Rel 96 Rel 97 Rel 98
GPRS
Rel 99 Rel 4 Rel 5
UTRA
IMS
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
42
Basic Architecture (Phases 1 and 2)
HOME
GSM Radio
Circuit domain
43
Εισαγωγή του GPRS
Packet domain
HOME
GSM Radio
Circuit domain
44
Εισαγωγή του UMTS
Packet domain
UMTS Radio
HOME
GSM Radio
Circuit domain
45
Εισαγωγή του IMS
Packet domain
IMS
UMTS Radio
HOME
GSM Radio
IMS
Circuit domain
46
Στοιχεία του IMS
Home
Call Session
Control Function
Home Subscriber
Server
HSS
I-CSCF
S-CSCF
Supports and controls the
multimedia sessions, providing
the flexibility to add, modify or
delete bearers used by the
user’s services
Other IP/IMS
network
MRF
Multimedia Resource
Function
UTRAN
SGSN GGSN
IMS
P-CSCF
Serving PS domain
47
Serving-CSCF:
Details
of IMS
Performs the Session
Control: handles the SIP
requests and forwards
HSS
them to the S-CSCF
/external IP network of
other end user.
The S-CSCF might be
specialized for the
provisioning of a (set of)
service(s).
UTRAN
Details of IMS
S-CSCF
I-CSCF
MRF
Multimedia Resource
Function:
Handles multiparty
and conferences
P-CSCF
SGSNcalls
GGSN
Interrogating-CSCF:
Other IP/IMS
network
“main entrance”
of
the home network:
Selects (with the
help of HSS) the
appropriate S-CSCF.
Proxy-Call Session Control Function:
“first contact point” of IMS: located in the visited network, selects the ICSCF of the Home Network of the user.
Performs some local analysis (e.g. number translation, QoS policing,..)
48
Details of IMS
HSS
S-CSCF
Legacy mobile
signalling
network
R-SGW
UTRAN
I-CSCF
Other IP/IMS
network
MRF
SGSN GGSN
P-CSCF
BGCF
MGCF
Many interworking functions and
entities defined for interconnection
with legacy networks (PSTN,
GSM, GSM+GPRS, UMTS, etc.)
T-SGW
Transport
IM-MGW
Signalling
Legacy, PSTN
49
Details of IMS
Cx
HSS
Mw
Cx
Mm
Mh
Legacy mobile
signalling
network
R-SGW
S-CSCF
I-CSCF
Other IP/IMS
network
Mc
Ms
MRF
Mw
Mi
Gi
Mk
Mg
UTRAN
SGSN GGSN
Gi+Go
Mj
P-CSCF
MGCF
Gi
BGCF
T-SGW
Mc
IM-MGW
Transport
Signalling
Legacy, PSTN
50
Principle of IMS procedures
HSS
S-CSCF
I-CSCF
Other IP/IMS
network
MRF
UTRAN
SGSN GGSN
P-CSCF
1. Establishment of Transport
Bearers and PDP context
51
Principle of IMS procedures
4. IMS Registration
and subsequent
interactions between
UE and S-CSCF and
HSS
with external
network(s)
S-CSCF
I-CSCF
3. Contact
OtherI-IP/IMS
network
CSCF in Home
MRF
UTRAN
SGSN GGSN
P-CSCF
2. Discovery by GGSN of P-CSCF and
UE request sent to P-CSCF
52
Overview of Protocol Stack
S-CSCF
I-CSCF
SIP signalling
UTRAN
SGSN GGSN
P-CSCF
User data
53
Overview of Protocol Stack
SIP
SIP
IMS Signalling
UDP
UDP
UDP
IPv6IP v6
IP v6
UDP
IPv6
IP v6
PDCP
GTP-U
GTP-U
GTP-U
GTP-U
RLC
RLC
UDP/IP
UDP/IP
UDP/IP
UDP/IP
PS AAL5
domain
transport
MAC
L2
AAL5
L2
L1
L1
ATM
Uu
ATM
L1
L1
Iu-PS
UTRAN
UDP
UDP
IPv6
IP v6
Relay
PDCP
MAC
SIP
SIP
IPv6IP v6
IP v6
Relay
MS
SIP
SIP
SIP
SIP
Gn
3G-SGSN
IP
IP
L2
AAL5
AAL5
L1
ATM
ATM
Backbone transport
Gi
3G-GGSN
Transport
Layers
Transport Transport
Layers
Layers
Transport Transport
UDP
Layers
Layers
Transport
UDP
Layers
Mw
Mw
P-CSCF
P-CSCF
I-CSCF
S-CSCF
S-CSCF
54
Flows already defined





Registration (UE initiated) and de-registration (UE and network initiated)
Establishment of an IMS session in cases (different roaming scenarios plus
PSTN or IMS initiated/terminated calls)
Session Release: initiated by UE, by CN (by P- or S-CSCF, by UTRAN –
loss of radio- or loss of signaling PDP context), by PSTN
Call hold/resume, codec and media flow negotiations, addition of another
media
Session redirection (6 different cases), session transfer (i.e. redirection
after establishment)
55
Parlay/OSA:
an open API for service development
Outline
0- Introduction: the Parlay/OSA API: why, where, what?
1- A closer look at Parlay/OSA
- Parlay/OSA Framework and Service Capability Features
- Parlay/OSA current functionality
2- The Parlay/OSA Framework
- Framework functionality
- How does it work?
3- Example Parlay/OSA applications
57
Outline
4- Parlay/OSA standardisation
- Bodies involved in Parlay/OSA standardisation
- The Joint API Group
5- The next Parlay/OSA release
6- Summary, contacts
58
Outline
0- Introduction: the Parlay/OSA API: why, where, what?
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
59
The Parlay/OSA API: Why? (1/2)
A change in business models has introduced new players in the
telecom business
Some want to address
users directly
Some prefer to do it
via the Network Operator
connectivity
+ services
connectivity
User
Operator
services
User
Operator
connectivity
connectivity
New Player
New Player
But they have something in common:
They compete in the services market...
and they have no network!
60
The Parlay/OSA API: Why? (2/2)
This is a win-win situation!
- It opens new sources of revenue for incumbent Network
Operators
- traffic in their networks increases
- they may enrich their service offering
- It opens the telecom business to newcomers
- VNOs, MVNOs, ASPs, ...
So we only need a technical enabler:
Parlay/OSA
61
The Parlay/OSA API: Where? (1/2)
Parlay / OSA
Services/application
layer
OSA/Parlay API’s
exposing
network service
capabilities
Control layer
Service Capability Servers
Connectivity layer
Core & Radio Networks
2G 2.5G & 3G
Distribution via
middleware
62
The Parlay/OSA API: Where? (2/2)
The UMTS Example
SIP AS
OSA Service
OSA
OSA SCS
ISC
Sh
ISC
S-CSCF
Cx
CAMEL App
CAP
IM SSF
ISC
MAP
HSS
63
The Parlay/OSA API: What? (1/2)
Parlay/OSA (Open Service Access) is an API that enables operator
and 3rd party applications to make use of network functionality through
a set of open, standardised interfaces
App1
App2
AppN
Parlay/OSA API
OSA Gateway
Applications (independent of
underlying network technology)
3GPP
ETSI
Parlay
JAIN
Mapping to network specific protocols
Network
Network complexity hidden from
applications
64
The Parlay / OSA API: What (2/2)
Opening up of network by means of standardized APIs based on open
technology. This leads to :

Shorter TTM for applications / services due to abstraction and open technology
(developer community orders of magnitude larger than telco developer community)

Applications can also be developed and deployed by 3rd parties (creative, new
innovative services).

Applications can be network independent (multi-access / multi-service)

Applications can be combination of
–
–
different capabilities
enterprise data with network functionality
leading to new innovative services.
65
Outline
0- Introduction
1- A closer look at Parlay/OSA
- Parlay/OSA Framework and Service Capability Features
- Parlay/OSA current functionality
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
66
Parlay/OSA Terminology: SCSs and SCFs
- The Parlay/OSA Gateway consists of several Service
Capability Servers (SCS): functional entities that
provide Parlay/OSA interfaces towards applications.
Interface
SCF
- Each SCS is seen by applications as one or
SCS
more Service Capability Features (SCF):
abstractions of the functionality offered by
the network, accessible via the Parlay/OSA
API. Sometimes they are also called
services
- The Parlay/OSA SCFs are specified in terms
of interface classes and their methods
67
Parlay/OSA = Framework + A Set Of SCFs
Application
server
Application
OSA API
framework
User
Call control
Service capability servers
Location
interface
class
Not standardized
OSA Internal API
HLR
CSE
----
Servers
E.g. Location server
Billing server
One of the Parlay/OSA SCSs is called the Parlay/OSA Framework,
and is always present, one per network
68
Outline
0- Introduction
1- A closer look at Parlay/OSA
- Parlay/OSA Framework and Service Capability Features
- Parlay/OSA current functionality
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
69
Basic Parlay/OSA SCFs
Call Control
The Call Control family, with capabilities ranging from setting up basic calls to manipulating
multimedia conference calls (see Note 1)
User Interaction Obtain information from the end-user, play announcements, send short text messages, etc
User location /
User status
Obtain location and status information
Terminal
capabilities
Obtain the capabilities of an end-user terminal
Data session
control
Control of data sessions
Generic
Messaging
Access to mailboxes (see Note 2)
Connectivity
Management
Provisioned QoS (see Note 2)
Account
Management
Access end-user accounts
Content based
Charging
Charge end-users for use of applications / data
Note 1: Multimedia and Conference Call Control not part of 3GPP OSA Release 4
Note 2: Not part of 3GPP OSA Release 4
70
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
- Framework functionality
- How does it work?
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
71
The Parlay/OSA Framework
- control of access to the network
- integrity management
- discovery of network functionality
Client Application
Enterprise
Operator
4
1
2
2
Framework
Call
Control
Mobility
3
etc
Registered Services
- Application subscription
to services
- SCF registration
- support of multi-domain
72
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
- Framework functionality
- How does it work?
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
73
How does the FW work ?
Application
4: authentication
5: request Discovery interface
6: discover Service
7: Select Service + sign SLA
10: return Service Manager
11: Use service
1: authentication
2: request Registration interface
Framework
3: register factory
8: create Service Manager
9: return Service Manager
Service /
SCS
74
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
- Framework functionality
- How does it work?
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
75
Information Application
The user dials in to the application to access information,
• traffic
• weather,
• stocks,
• etc
via voice.
76
Information Application : interaction flow before
traffic
The Application registers to the Framework
The Framework starts a suitable Call Manager, and
passes a reference to the application
77
Information Application : interaction flow during
traffic
User calls service number
SCS checks subscription to service
Information presented to user via UI SCS
Application charges subscriber
(either via Charging API, or indirectly
via CC API)
78
Location Service
This is an example of combination of enterprise data with
network capabilities
Bank services
Location services
Leisure
News
79
Location Service
The idea is that the user is able to find out the nearest
ATM machine
Directions
From
Default
To
ATM
Bank
Police
80
Location service
81
Location service: interaction flow during traffic
The terminal interacts via WAP with application, selects ATM
location option
Application Server
The application invokes ‘userLocationRequest’ method, gets
response
Application
The application produces suitable map (including term.caps from
WAP GW), provides this to terminal
OSA Interface
FW
User Location
SCS
PLMN
(GSM/UMTS CS)
CC/UI
SCS
WAP
GW
PSTN/ISDN (CS)
82
Unified messaging application
The application allows user to access all his messages.
This is an example of combination of information in different
business domains
83
Unified messaging application: interaction flow
The user sets messaging preferences (private and
corporate combined if desired) via Web/WAP
(or via voice recognition)
Notifications of different messages, plus actions, are
handled by the application
84
Outline
0- Introduction
1- A closer look at OSA
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
- Bodies involved in Parlay/OSA standardisation
- The Joint API Group
5- The next Parlay/OSA release
6- Summary, contacts
85
Bodies Involved In Parlay/OSA Standardisation
OSA specification and standardisation is a joint
effort by the following bodies:
- 3GPP CN5
- ETSI SPAN12
- ITU-T SG11 (only ref. document)
- The Parlay Group
The objective is to have a single API for the whole
developer community
86
OSA (Parlay) In 3GPP
3GPP
Core Network
(CN)
SIP
CAMEL
Radio Access Network
(RAN/GERAN)
...
Terminals
(T)
Services and System
Aspects (SA)
OSA
OSA stage 3:
protocols
Services
OSA stage 1:
requirements
Architecture
+coordination
Security
Codec
Telecom
mgmt
OSA stage 2:
architecture
87
OSA (Parlay) In ETSI
- ETSI SPAN (Services and Protocols for Advanced Networks) was
re-organized
- The group ETSI SPAN12, Application interfaces for service
providers and network operators, was created
- An activity in ETSI SPAN14, called Service Provider Access
Requirements (SPAR), was also created
- ETSI SPAN12, aware of the identical scope of the work in 3GPP
CN5, agreed to work jointly and make
all meetings joint meetings
- Today ETSI SPAN12 has an OSA Project, part of the Joint API
Group and working also on OSA/Parlay Compliance
88
OSA/Parlay In ITU-T
- ITU-T SG11 has defined a Question 4 called
API/Object interface and architecture for signaling, “covering the
interface between network control and application layers”
- ITU-T has decided to write a reference document for this activity,
and delegate the contents to other bodies
- This way ITU-T will adopt OSA specifications by ETSI (+3GPP
+Parlay)
- ITU-T SG11 draft document is called TD 1/11-25
89
Parlay (OSA) In The Parlay Group
- The Parlay Group (www.parlay.org) started in March 98, and today is
an open, multi-vendor forum with around 50 members from the IT
and Telecom business
- The Parlay Group aims to create open, technology independent
APIs which enable developing applications across multiple networks
(=OSA!); and to accelerate the adoption of these APIs and promotes
their use and standardisation.
- Technical work in the Parlay Group is done in Work Groups; the
Parlay WGs have joined the 3GPP+ETSI OSA (Parlay) joint group to
develop together a single API
90
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
- Bodies involved in Parlay/OSA standardisation
- The Joint API Group
5- The next Parlay/OSA release
6- Summary, contacts
91
Today’s Parlay/OSA Joint Activities
- Today 3GPP, ETSI and Parlay have joined forces to specify a single
API for the whole developer community
- Requirements coming from the three participating bodies are taken
into account:
- 3GPP requirements from SA1 and SA2
- ETSI requirements from SPAN14 SPAR
- Parlay requirements from the Parlay Group
- All meetings are joint meetings
- The joint work is (UML) based on a common model,
http://docbox.etsi.org/tech-org/span/open/span12/UML/
Then each body generates its own document format
92
API’s for Open Service Access; ONE API for ONE developer
community
1.) Requirements
introduced
by individual bodies
JAIN
Joint API
Group
2.) create the API
that supports the superset
of all requirements.
(Joint meetings)
Current Workflow
Reference in ITU-T Roadmap
3.) Results are
transferred back to
individual bodies
 UMTS
 OSA (Open Service Access)
 PSTN/ISDN
 OSA (Open Service Access)
93
Joint Work Synchronization
2001
1Q
2Q
2002
3Q
Parlay 2.1
4Q
3.0
1Q
2Q
3Q
4Q
3.1
4.0
ETSI
1.0
1.1
2.0
3GPP
Release 4
4.0
4.1
4.2
4.3
Release 5
No further changes accepted
5.0
5.1
5.2
5.3
= point of alignment between specifications
94
Alignment and backwards compatibility
- The current last versions of the three bodies are fully aligned
3GPP Rel4  ETSI Ver1  Parlay 3
- None of them is backwards compatible with any of its previous
releases/versions, due to changes based on feedback from
implementers
- From now on backwards compatibility is a must
95
3GPP Parlay/OSA Rel4 Document Structure (1/2)
The Parlay/OSA API is contained in two sets of documents:
- The API specification in terms of interfaces and their parameters
(UML description and IDL specification), sequence diagrams and
state models
- The Mapping specification of the Parlay/OSA API and network
protocols : a possible, informative mapping from the API to various
network protocols (i.e. MAP, CAP,..)
96
Parlay/OSA Document Structure (2/2)
The specification is in turn contained in the following documents:
- 3GPP : TS 29.198 /12 parts (API) + TR 29.998 (Mapping)
http://www.3gpp.org/ftp/Specs/200112/Rel4/29_Series
- ETSI : ES 201 915 (API) + TR 101 917 (Mapping)
http://docbox.etsi.org/tech-org
/span/Open/Span12/osa.html
- Parlay
http://www.parlay.org/specs/index.asp
Choose your favorite: all are aligned!
97
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
98
Ongoing Work for Parlay/OSA
Based on requirements from all the bodies in the joint activity,
Parlay/OSA is enhanced with:
03/02:
- MM Call Control evolution
- Presence Service
- Policy Management
07/02:
- Retrieval of Network Capabilities
- Information Services
- User Profile Management
- Journalling
... plus enhancements in the existing SCFs
99
Outline
0- Introduction
1- A closer look at Parlay/OSA
2- The Parlay/OSA Framework
3- Example Parlay/OSA applications
4- Parlay/OSA standardisation
5- The next Parlay/OSA release
6- Summary, contacts
100