R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS
The CAMEL - where is it going ?
Stefan Aprath
ETSI PT SMG Sophia Antipolis
seconded by Mannesmann Mobilfunk GmbH
Contact Information
For general enquiries to ETSI:
ETSI Infocentre
Ph: +33 4 9294 42 22; Fax: +33 4 92 94 43 33; Email: infocentre@etsi.fr
ETSI Secretariat
650 Route des Lucioles - Sophia Antipolis
Valbonne - FRANCE
Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16
X.400: c= fr; a=atlas; p=etsi; s=secretariat
Internet secretariat@etsi.fr ; http://www.etsi.fr
Postal address: F-06921 Sophia Antipolis Cedex - FRANCE
ETSI PT SMG Secretariat
Ph: +33 4 9294 42 66; Fax: +33 4 93 65 28 17; Email: carole.rodriguez@etsi.fr
Stefan Aprath
Ph: +33 4 9294 43 24; Fax: +33 4 93 65 28 17; Email: stefan.aprath@etsi.fr
2
Introduction: Why IN in
Mobile Networks ?
Operators / Service Providers like:
–
–
–
Rapid creation of new services
Low dependency on switch manufacturer
Reduced services operating costs
Users like:
–
Advanced Services everywhere
Wireless application of IN as a means to
provide Operator Specific Value Added
Services will take the lead !
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Introduction: Why IN in Mobile Networks ?
IN concept separates service logic from switch based architecture, allowing non standardized
services through standadized interfaces. This has many advantages:
Operators like: Services can be rapidly created by the service provider/ network operator, short
reaction time to market requirements without dependence on switching equipment vendor or
system standards (lead time 6 month), No long term alignment of vendor offerings, differentiation
between operators, sharing of resouces by concentrating service logic on a commercial hardware
platform, allow optimize routeing, software re-use (SIBs). Reduced operating costs because services
can be introduced to the networks without 'overnight roll-out' and maintained centrally.
Users like: Access to advanced services everywhere, Improved reachability with maintained privacy,
tailored personalized services, easy to use services (VPN) and customer service control , flexible
charging solutions (debit card, calling party pays), convergence of distinct telecommunication
networks (DECT, fixed, GSM)
Mobile Networks are fast growing telecommunication sector (Mobile telecommunication services
from status symbol to business tool to consumer product), (in europe: first time full competition for
telecommunication services and also between system vendors, Operators pursue new marketing
approaches, differentiation pressure, modern mobile networks have less legace network equipment)
=> Wireless application of IN as means to provide Operator Specific Value Added Services will
take the lead !
4
Presentation Outline
Part 1:
1: The
The GSM
GSM vehicle
vehicle to
to Operator
Operator
Part
Specific Services:
Services: CAMEL
CAMEL
Specific
Part 2: CAMEL between GSM and IN
Part 3: CAMEL phase 1 & 2: Features
Part 4: On CAMEL’s back into the future
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5
What is CAMEL and
where did it come from ?
"Customized
Application for Mobile
network E
Enhanced Logic"
CAMEL is a toolbox
based on IN technology
CAMEL is a network
based feature in GSM
CAMEL is standardized
in ETSI SMG
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SIB
SIB
SIB
SIB
SIB
SIB
Stefan Aprath, PT SMG
6
FAQ: What is CAMEL and where did it come from ?
"Customized Application for Mobile network Enhanced Logic" (It can hardly be denied that the
inventors had some marketing thoughts in mind)
CAMEL is a toolbox based on IN technology
CAMEL is applicable to - Mobile Originating (MO) and Mobile Terminating (MT) calls,
Supplementary service invokation (in Phase 2)
CAMEL is a network based feature in GSM
CAMEL is a workitem in ETSI Special MobileGroup standardization for GSM to allow IN services to
be available from visited networks
Note: SIB stands for Service Independent Building block, which is a piece of software.
6
What were the drivers in
GSM ?
GSM operators can
– Increase revenues by
–
–
–
–
Acquire competitive advantages by
–
–
–
offering new services to current customers (meet subscriber
requirements)
attract new subscribers (enter market segments),
Reduce service operating costs
differentiate from competitor in service offering
bringing new services faster to the market
Be prepared for deregulation by
–
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implementing physical interfaces for future service
providers
Stefan Aprath, PT SMG
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7
.. which is achieved by
–
–
–
control fraud (monitor subscriber actions, immediate
Service Provider reaction )
offer new GSM services (Call Screening, Enhanced Call
forwarding, SPNP,..)
offer new Operator specific value added services
services common to fixed and mobile users
services for mobile users (location dependent services)
–
–
Separate service specific data from switch functionality
(multiple databases)
offer flexible charging mechanisms
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CAMEL: A Standard’s Animal
CAMEL is a GSM Phase 2+ Feature.
Phase 1 is part of GSM Release 96:
Jun. 1996 Stage 1 description of CAMEL
phase 1 approved at ETSI SMG#19
Feb. 1997 CAMEL phase 1 Stage 2 and
Stage 3 (CAP) approved at ETSI
SMG#21
R96
>x
.5
CAMEL is specified by the following specifications:
GSM 02.78, 03.78, 09.78 (CAP)
GSM 03.18, 09.02 (MAP)
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CAMEL is a workitem in ETSI Special MobileGroup standardization for GSM to allow IN services to
be available from visited networks
1994: First drafts specifications in ETSI SMG1 (Services) in early 1994, then called SOSS (Support of
Operator Specific Services), later renamed to CAMEL.
Feb. 1995 Workshop in Brussels on The Evolution of GSM towards IN.
Specification work is carried out by SMG1 (services) ad hoc and SMG3 WPC (network aspects)
CAMEL is a GSM Phase 2+ Feature, i.e. its implementation is an optional enhancement to the Phase 2
Platform.
CAMEL is specified by the following specifications:
GSM 02.78 Stage 1 Service description
GSM 03.78 Stage 2 Service description (Call model, SDLs)
GSM 09.78 Stage 3 CAMEL Application Part (CAP)
GSM 03.18 GSM Basic Call Handling
GSM 09.02 Mobile Application Part (MAP)
9
Status of CAMEL phase 2 in
ETSI SMG (GSM Release 97)
Vorgangsname
first draft agreed
7
Qtr 2, 1997
Finish Variance
Mar Apr May Jun
Jul
Qtr 3, 1997
Aug Sep
Oct
Qtr 4, 1997
Nov Dec
Qtr 1, 1998
Jan Feb Mar
24/04/97 17:00
final input from CAGE+
10/06/97 08:00
stage 1 approved by SMG1
27/06/97 17:00
Create stage 2 description (CR33d
03.78)
20
Framework Stage 2 (CR 03.78)
25/04/97 17:00
First draft of stage 2 agreed
27/06/97 17:00
Technical solutions agreed41d
within SMG3WPC
31
20/10/97 00:00
08/09/97 08:00
Stage 2 approved by STC [optionally
by correspondance]
33d
35
36
38
49d
08/09/97 00:00
First draft stage 3 (CR 09.78,
09.02)
48d
41
46
17/11/97 17:00
41d
20/10/97 00:00
46d
02/01/98 17:00
stage 3 and MAP approved 41d
by STC
47 Approval of WI at SMG
04/02/98 17:00
59d
2
50
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GSM Release 97: The Project Plan for CAMEL phase 2:
The SMG decision to develop GSM in yearly releases promted a strict project plan for CAMEL phase
2.
Part of this was careful analysis and prioritization of features. Evaluation of complexity versus
priority. Progress in standardization is closely monitored to allow management decsions based on
objective data.
10
The overall design goals for
CAMEL (1)
Specification for CAMEL must cater for
New Operator specific value added services services
without standardization in SMG
…….. which still work when roaming !
Ease introduction of services in a multivendor GSM
architecture (CAMEL phase 2)
Base services on a single platform under the control of the
home network operator
Minimize impact on GSM classic services and their
integrity
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The overall design goals for
CAMEL (2)
Take the GSM architecture into account, minimize costs
and impact on existing nodes and network interoperability
Use of MAP between existing GSM entities
Allow smooth integration, and smooth extension of
applicability of home network services to fully mobile
service in global scale !
The phased approach
Re-use functionality as much as possible that are already
invented for fixed network IN CS-x
Use of INAP between the Service Control and Service
Switching
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CAMEL - offspring of ETSI
Core INAP and ITU IN CS-x (1)
CAMEL phase 1 and phase 2 are based on ETSI Core
INAP CS-1 !
Out of scope for CAMEL: Service Control Function, Data
Function, Service Management Function, Service Creation
Function
CAMEL must remedy some IN-CS-1 shortcomings by
eliminating options,
being normative, assuring 100% vendor compatibility
optimize signalling efficiency,
define a marketing driven Set of features
add mobile specific functionality and parameters
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CAMEL does not specify service logic in the CSE (SSP) and no other interface than CAP and MAP > SDP, SMP to SCP interface is not specified.
CAMEL needs to be normative, assuring 100% vendor compatibility (avoid additional testing
between roaming partners; In theory: n networks mean r=(n-1)n/2 Roaming agreements. n today =
204; r=20706
CAMEL must define a marketing driven Set of features (subset of CS-1) in order to minimize the
implementation cost imposed on networks to benefit roaming
13
CAMEL - offspring of ETSI
Core INAP and ITU IN CS-x (2)
Goal: Convergence of IN-CSx and CAMEL. Integration
of GSM specific requirments into ETSI CS-2 and ITU
CS-3.
more features from IN CS-1 will be incorporated into
CAMEL phase 2 and 3
some features from IN CS-2 will be adopted by
CAMEL phase 3
some requirements from CAMEL will be incorporated
into ETSI core INAP CS-2 (Convergence of technical
solution also with CTM) and subsequently to IN CS-3.
Closing the gap from both sides !
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Part 1: The GSM vehicle to Operator
Specific Services: CAMEL
Part 2: CAMEL between GSM and IN
Part 3: CAMEL phase 1 & 2: Features
Part 4: On CAMEL’s back into the future
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How CAMEL fits into GSM
Terms in GSM, IN and CAMEL
–
–
HLR, VLR, GMSC, VMSC,
OSS, gsmSSF, gsmSCF, CSE, CSI
Key choices:
International interface: MSC/gsmSSF <-> CSE
Subscriber specific CAMEL invocation via Camel
Subscription Information (CSI)
CAMEL handling at GMSC for terminating and
forwarded calls, at VMSC for originating calls
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General terms in GSM (1):
Operator Specific Service (OSS): Any service offered on a PLMN that is not standardised by the GSM suite of
specifications.
CAMEL Service Environment (CSE):
GSM speak for SCP. A CSE is a logical entity which contains the
service control function gsmSCF for processing activities related to OSS. The CSE is under the control of the CAMEL
subscriber’s Home network operator.
CAMEL Subscription Information (CSI):
The CSI identifies the CAMEL support required for the subscriber
and the identities of the CSEs used for that support. The CSI also contains information related to the OSS of the subscriber,
e.g. Service Key. Used are O-CSI and T-CSI distinguish between CSI that is applicable to Mobile Originating (MO) or
Mobile Terminating (MT) calls.
O-CSI
CSI applicable to mobile originating and forwarded calls
T-CSI
CSI applicable to mobile terminating calls
GSM Service Switching Function (gsmSSF)
A functional entity that interfaces the MSC/GMSC containing the
call control function to the gsmSCF containing the service control function. The concept of the gsmSSF is derived from the
IN SSF, but uses different triggering mechanisms because of the nature of the mobile network.
GSM Service Control Function (gsmSCF)
It is part of the CSE that communicates with the gsmSSF A
functional entity that contains the CAMEL service logic to implement OSS. It interfaces with the gsmSSF and the HLR.
Mobile-services Switching Centre (MSC) An MSC can act as GMSC or VMSC:
VMSCvisited MSC
The Mobile-services Switching Centre is an exchange which performs all the switching
and signalling functions for mobile stations located in a geographical area designated as the MSC area. The VMSC has to
take into account the impact of the allocation of radio resources and the mobile nature of the subscribers.
When processing the calls for subscribers requiring CAMEL support the MSC monitors on request the call states (events) and
informs the gsmSSF of these states during processing enabling the gsmSSF to control the execution of the call in the MSC.
GMSC Gateway MSC
where the mobile station is located.
This MSC will interrogate the appropriate HLR and then route the call to the MSC
When processing the calls for subscribers requiring CAMEL support the GMSC receives a O/T-CSI from the HLR,
indicating the GMSC to request instruction from the gsmSSF. The GMSC monitors on request the call states (events) and
informs the gsmSSF of these states during processing enabling the gsmSSF to control the execution of the call in the GMSC.
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General terms in GSM (2):
HLR Home Location Register
This functional entity is a data base in charge of the management of mobile
subscribers. A PLMN may contain one or several HLRs: it depends on the number of mobile subscribers, on the
capacity of the equipment and on the organisation of the network. Two kinds of information are stored there:
-
the subscription information;
-
some location information enabling the charging and routing of calls towards the MSC where
the MS is located (e.g. the MS Roaming Number, the VLR address, the MSC address, the
Local
MS Identity).
Two types of number are attached to each mobile subscription and are stored in the HLR:
-
the International Mobile Station Identity (IMSI);
-
one or more Mobile Station International ISDN number(s) (MSISDN).
All subscribers, that subscribe to originating or terminating services provided by CAMEL, are marked in the HLR by
having the CAMEL Subscription Information (CSI) stored against them. The O-CSI is sent to the VLR in case of
Location Update. The O/T-CSI is sent to the GMSC when the HLR responds to a request for routing information.
VLR Visitor Location Register
A mobile station roaming in an MSC area is controlled by the Visitor Location
Register in charge of this area. When a Mobile Station (MS) enters a new location area it starts a registration procedure.
The MSC in charge of that area notices this registration and transfers to the Visitor Location Register the identity of the
location area where the MS is situated. If this MS is no yet registered, the VLR and the HLR exchange information to
allow the proper handling of calls involving the MS, called Location Updating.
If the subscriber is marked as having OSS using CAMEL, the VLR stores the O-CSI for that subscriber.
PLMN
Public Land Mobile Network
VPLMN
This is the PLMN where the VMSC is located.
Interrogating PLMN (IPLMN):
This is the PLMN that performs the interrogation of the HPLMN for information
on the treatment of the terminating call. It is the PLMN where the GMSC is located.
Network operator The owner of GSM infrastructure. The home network operatore ownes in particular the HLR, and
also CSE.
Service Provider Has the contractual relationship to the customer. Can offer service using the network operator's
infrastructure.
Intelligent Peripherial (IP)
This is a physical entity that contains the SRF.
Specialized Resource Function (SRF)
A functional entity which provides various specialized
resources, e.g. Announcement machines, DTMF detector, Text to Voice conversion, etc.
SDF
Servcie Data Function: Stores data pertaining to OSS. It is outside the scope of GSM
Basic Call State Model BCSM:
The BCSM provides a high-level model of GMSC- or MSC/VLR-activities
required to establish and maintain communication paths for users. As such, it identifies a set of basic call activities in a
GMSC or MSC/VLR and shows how these activities are joined together to process a basic call.
Service Key:
An identifier of the OSS which shall be transparent to the IPLMN/VPLMN.
Advice of Charge (AoC)
and react in case a limit is exceeded.
On line charging service that allows display of charging information on the MS
Detection Points (DP):
The points in processing at which notifications (to the service logic) can occur and
transfer of control (to the gsmSCF) is possible are called Detection Points (DPs).
MAP
Mobile application part (GSM 09.02)
CAP
CAMEL application part (GSM 09.78)
17
The ‘classical’ GSM
functional architecture
without CAMEL, GPRS and ASCI
Home Network
AuC
HLR
MAP
SIWF
MAP
EIR
VLR
Incoming line
Roaming leg
GMSC
MS
MO call - Outgoing leg
Forwarded leg
(or Forwarding leg)
Interrogating Network
–
MSC
Visited Network
The interrogating network is the home network unless Optimal
Routeing is used
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AuC: Authentication Center
SIWF: Shared Data Interworking Function
ASCI: Advanced Speech Call Items (UIC PMR features)
The functional entities above are not further discussed.
An important factor that needed to be consedered when applying IN to GSM architecture is the very
specific handlings for GSM call forwarding:
1. Early CF at the GMSC due to HLR detected absent subscriber or unconditional CF
2. Late CF at the VMSC after the call has been extended for reasons of subscriber busy or no reply.
18
Evolving to ‘CAMEL’ GSM
architecture Phase 1
Home Network
MAP
HLR
gsmSCF
CSE
CAP
CAP
Incoming line
MAP
VLR
gsmSSF
GMSC
Roaming leg
gsmSSF
MSC
MS
MO call - Outgoing leg
Forwarded leg
(or Forwarding leg)
Interrogating Network
Visited Network
The integrated MSC/SSF approach
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Here: The integrated approach, i.e. SSP in each MSC, alternative: overlay configuration with
rerouting to specific SSPs.
HLR: The HLR stores the O/T-CSI for subscribers requiring CAMEL support. The O-CSI is sent to
the VLR in case of Location Update or if the O-CSI is updated. The O/T-CSI is sent to the GMSC
when the HLR responds to a request for routing information. The HLR may provide an interface
towards the gsmSCF for the Any Time Interrogation procedure.
GMSC: When processing the calls for subscribers requiring CAMEL support the GMSC receives a
O/T-CSI from the HLR, indicating the GMSC to request instruction from the gsmSSF. The GMSC
monitors on request the call states (events) and informs the gsmSSF of these states during processing
enabling the gsmSSF to control the execution of the call in the GMSC.
MSC: When processing the calls for subscribers requiring CAMEL support the MSC receives a OCSI from the VLR indicating the MSC to request instruction from the gsmSSF. The MSC monitors on
request the call states (events) and informs the gsmSSF of these states during processing enabling the
gsmSSF to control the execution of the call in the MSC.
VLR: The VLR stores the O-CSI as part of the subscriber data for subscribers roaming in the VLR
area.
Roaming agreements: Contractual relationship between network operators for the purpose of
providing serviceto subscribers roaming to visited networks.
19
……and CAMEL Phase 2
Home Network
HLR
gsmSCF
CSE
MAP
Incoming line
VLR
gsmSSF
GMSC
Roaming leg
gsmSSF
MSC
MS
MO call - Outgoing leg
Forwarded leg
(or Forwarding leg)
Interrogating Network
CAP
Visited Network
gsmSRF
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H-,I-,VPLMN
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gsmSRF:The specialized resource function provides a pool of resources for access by other network
entities. These resources include for example sending of announcements to the parties in a call,
prompt for information using DTMF sending and receiving, speech recognition, synthesized speech
provision, protocol conversion, specialized connection resources (e.g. audio conference bridge or
information distribution bridge)
20
Call Set-up with CAMEL
Call set up is attempted
MSC determines with VLR that OSS are requested.
If criteria are met, suspend the normal call processing,
contact the SCE and wait for instructions on how to
continue
SCE acts according to the Service Logic
–
–
–
–
connect the call (e.g. to a new address)
connect to a specialized resource function
continue the normal call handling -> no CAMEL service
release the call
The call is continued with instructions (e.g. for charging)
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The Principle of IN: BSCM
Ringing tone
Dial short
number
Conversation………….
END
MSC/SSP
EDP
TDP
MS
idle
Check
Authori
zation
Analyse Route call
to
CSI,
criteria destination
EDP
EDP
Called Monitor active call
Party
answers
CAP
CSE
Trigger Service
LogicVPN:
Database inquiry
Reconnect: Change
called number
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Get Call Information, Send Charging
information
Stefan Aprath, PT SMG
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BCSM: Basic Call State Model, a finite state machine model that is used to describe the processing of
a call in the MSC or GMSC. It identifies certain Points in Call (PIC), where interaction with service
logic is possible.
TDP: Trigger Detection Point: If met in the BCSM, the CSE is contacted for the first time
EDP: Event Detection Point: If requested by the CSE, the event described by the EDP is reported.
22
The CAMEL Subscription
Information (CSI)
Administered and stored in HLR per subscriber !
Different CSI for originating (O-CSI) and
terminating (T-CSI) calls
CSI contains
–
–
–
–
Service Key (identifies the service logic)
address of the CSE to be contacted
Default call handling
Criteria for contacting the CSE
e.g. Dialled Number, Basic Service
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The Camel Subscription Information (CSI)
- Is administered by the network operator in the HLR
- Originating (O-)CSI is transported to the VLR that serves the CAMEL subscriber (MAP operation:
InsertSubscriberData, ISD
- Terminating (T-) CSI is transported to the interrogating MSC (GMSC) at the time an incoming call
to the CAMEL subscriber arrives. (MAP operation: SendRoutingInfo Result). If the called subscriber
also has originating CAMEL services, O-CSI may be send at the same time.
Content of the O/T-CSI
-gsmSCF address to be contacted on originating (forwarding) or terminating call attempt (E.164
number)
-Service Key identifies to the gsmSCF the service logic that should apply.
-Default Call Handling indicating whether the call shall be released or continued as requested in case
of error in the gsmSSF to gsmSCF dialogue.
-TDP List indicating on which detection point triggering shall take place.
-Criteria to be fulfilled before the CSE is contacted (CAMEL phase 2).
-Translation Information Flag indicating whether short numbers shall be stored in the HLR without
format checks.(CAMEL phase 2)
There is other subscriber related information stored in the HLR indicating whether or not the HLR
shall send the location information or state of the called subscriber.
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GSM ‘Classic’ Incoming Call
Home Network
HLR
2
3, 4
Interrogating Network
Visited Network
5
VLR
1
1 Initial address Message (ISUP)
2 Send Routing Info (MSISDN)
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MSC
6
GMSC
7
MS
3 PRN
4 PRN ack (MSRN)
5 SRI Ack (MSRN)
6 IAM, 7 Radio Signalling
Stefan Aprath, PT SMG
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Note:
SRI: Send Routing Information
SRI ack: SRI Achnowledgement
PRN: Provide Roaming Number
MSRN: Mobile Station Roaming Number
IAM: Initial Address Message
24
GSM Incoming Call with CAMEL
Home Network
HLR
gsmSCF
CSE
4
6
2
Interrogating Network
3
7,8
9
Visited Network
5
1
VLR
gsmSSF
GMSC
10
1 Initial address Message (ISUP)
2 Send Routing Info (MSISDN)
3 Send Routing Info ack (T-CSI)
4 Initial DP (CalledPartyBCD service
key..)
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MSC
11
MS
5 Connect (CalledPartyNumber)
6 SRI(T-suppress)
7,8 PRN, PRN ack (MSRN)
9 SRI Ack (MSRN)
10 IAM, Radio Signalling
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Note:
SRI: Send Routing Information
PRN: Provide Roaming Number
MSRN: Mobile Station Roaming Number
T- Suppress: Parameter indicating to the HLR that is should not send the T-CSI again.
The fact that GMSC first obtains the CAMEL subscription information and in a second step the
routeing information of the called subscriber is referred to as 2-step interrogation.
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Part 1: The GSM vehicle to Operator
Specific Services: CAMEL
Part 2: CAMEL between GSM and IN
Part 3: CAMEL phase 1 & 2: Features
Part 4: On CAMEL’s back into the future
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CAMEL phase 1 - Features (1)
Mobile Originated (MO) calls:
Report a Call Setup attempt to the CSE. The CSE can then
Suspend the call handling and alter information relating to the
suspended process
Let the normal call handling resume or
Release the call
Activate further service events for potential invocation. These
events shall remain active only for the life-time of the
telecommunication service;
Report the successful or unsuccessful establishment of the call
Report the fact that an established call is disconnected
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Features of CAMEL phase 1
-Applicable to circuit switched Mobile originated and Mobile terminated
calls.
-Not applicable to Emergency calls. EMC are treated differently in GSM!
-Dialled digits from GSM Access Signalling (GSM 04.08) can be relayed to
the CSE, i.e. ‘*’, ‘#’.
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CAMEL phase 1 - Features (2)
Mobile Terminated (MT) calls:
Report a Call Setup attempt to the CSE. The CSE can then
Order Suppression of Announcements and tones for unsuccessful
MT calls (thus allowing announcements to be played from the
HPLMN in the subscriber's language)
Everything else as in the MO case.
Provision of Call Reference Number
Any time interrogation (ATI)
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Suppression of Announcements:
This feature was motivated by different requirements:
1) Avoid an announcement in the visited MSC in order to have the Release
cause value transported back to the GMSC and thus to the CSE.
2) Improve privacy (The location of the subscriber is not revealed by the
language of the announcement)
3) Allow other announcements to be played from the home network.
Call Reference Number:
In CAMEL phase 1 the charging means are extremely weak. The call
reference number is the only tool to correlate some call records of the CSE
to those received from the network.
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Everywhere and any time:
The AnyTime Interrogation
The CSE queries the HLR of a
subscriber at any time for:
Location Information:
–
Latitude
e.g. Geographical information
(according to GSM 03.32)
Longitude
Subscriber Status
–
–
–
CAMEL-busy
Network determined not
reachable
Assumed idle
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gsmSCF
Stefan Aprath, PT SMG
ATI
HLR
PSI
VLR
MSC
MS
29
A Mobile Service Component: The AnyTime Interrogation (ATI)
The CSE can interrogate the HLR (if it is entitled to do so, e.g. for subscriber belonging to the
HPLMN of the CSE or arrangements between operators) for information related to a particular
subscriber. The HLR will pass on this request to the VLR of the subscriber, using the Provide
Subscriber Information (PSI) MAP dialogue. The information may consists of:
1.Location Information:
-Geographical information : The coding is performed according to GSM 03.32. Longitude, Latitude
and shape are indicated with reference to the world geodetic system, WGS (also used for GPS)
-Cell ID indicates the global identity of the current or last cell which the subscriber is using or has
used. The VPLMN shall update the stored Cell ID at establishment of every radio connection and
whenever the subscriber is handed over between cells.
-VLR number is the number stored in the HPLMN.
-Location status indicating the time since location was last confirmed by radio contact.
-Location number is the number received on the incoming circuit (for an incoming call) or to be sent
on the outgoing circuit (for an outgoing call).
2.Subscriber Status: An indication of the status of a subscriber, determined by the state of the
subscriber’s MS. The subscriber status can take one of three values:
-Busy: the MS is engaged in a mobile-originated or mobile-terminated circuit-switched call.
-Network determined not reachable: the network can determine from its internal data that the MS is
not reachable. This includes detached and purged mobile stations.
-Assumed idle: any MS that is not CAMEL-busy or network determined not reachable.
29
Interactions with 'GSM classic'
Supplementary Services:
No interaction where possible
Integrity of barring Services
Operator is responsible to control adverse effects
Interaction with Call Forwarding
Support of Short number registration in Phase 2
Interaction with calling line identification services
Synergy with AoC and USSD in Phase 2
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30
Interactions of CAMEL with 'GSM classic' Supplementary Services:
In general, the operator should avoid provision of SS that have adverse effects.
Integrity of barring Services:
-Important when roaming, fraud control, operator determined barring
-In some cases, the barring can be circumvented by a CAMEL service. The operator has to ensure that
if this is critical, the service logic takes care of barring scenarios.
Interaction with Call Forwarding
-Important due to most popular SS, Mailbox interaction
-The CAMEL service can emulatethe GSM call forwarding or perform a rerouteing. In case a
forwarding takes place, outgoing CAMEL services may apply for the forwarding party !
-Use of short numbers needs special treatment in HLR
Interaction with calling line identification services
-The CSE may change the number displayed in the called subscribers display. It may not changed the
network internal calling party number (ISUP) which may be used for services like Malicious Call
Identification.
No interaction whereever possible
-Ease Service profile management
-Independent management of HLR and CSE service provisions.
Synergy where possible
- Enhancement of Advice of Charge Supplementary service (see below)
- Use of Unstructured Supplementary Services Data (see below)
The following services are invoked after the CAMEL service: CF, CH, CW, MPTY, Barring Outgoing
calls and Support of Optimal Routeing
The following services are invoked before CAMEL service: CUG, Barring of incoming calls
30
Roaming and Compatibility
Roaming in non-supporting network:
fallback to CAMEL phase 1
no access to mobile originated CAMEL services.
special treatment: no roaming allowed, apply ODB
Incoming call to a non-supporting interrogating
network:
Normal GSM call handling.
CAMEL phase 1 SSF contacts phase 2 CSE:
The CSE determines service handling
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31
Roaming in non-supporting network: HPLMN determines default handling: no roaming allowed,
apply ODB or tolerate no access to mobile originated CAMEL based services.
Roaming in non-CAMEL phase 2 supporting network: HPLMN determines if a fallback to
CAMEL phase 1 is allowed (CAMEL phase 1 O-CSI).
Incoming call to a non-supporting interrogating network: CAMEL based terminating services are
not supported. Normal GSM call handling. (If no optimal routeing is applied, the interrogating
network is the home network of the subscriber and is likely to support CAMEL!)
CAMEL phase 1 SSF contacts CAMEL phase 2 CSE: The CSE may decide on whether to perform
CAMEL phase 1 services or apply a default handling. The CAP protocol version provides the version
indication implicitly.
31
2
CAMEL phase 2 - New Features (1)
CAMEL phase 2 is true superset of CAMEL phase 1
Support of Specialized Resources (also via assisting SSP) at
almost any time of MO or MT calls
Improved Exception Handling in case of unsuccessful call
attempts
Improved Charging functions:
CSE control of AoC e-parameters
Inclusion of free-format charging information into regular GSM call
records
Call information transferred to CSE
Support of on-line charging by control of tariff switch and call
duration, Play tone before a forced release
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32
In order of priority (x):
1. Support of Specialized Resources (also via assisting SSP) at almost any time of MO or MT
calls
- announcements and tones played to the called or calling subscriber directly after call setup or after
an unsuccessful call establishment is detected or after the call is disconnected. The HPLMN operator
can administer those announcements.
-in-band subscriber interaction using voice prompting and information collection (DTMF based)
There was a high interest of operators (1) to include this feature into CAMEL phase 2. The assist
function was motivated (1) by the multivendor environment most operators are facing.
2. Subscriber Interaction with the CSE by using USSD
-Allow for Mobile Originated and Network originated USSD dialogues (see relation to other
workitems in GSM) at any time. Operator interest: (2).
3. Improved Charging functions:
All charging functions had a high priority (1), especially because CAMEL phase 1 did not provide any
tools except the call reference number which could be used with great difficulty.,
-On-line charging by support of GSM AoC e-parameters for duration control and tariff switch.
-Delivery of charging information from the CSE to the served network for inclusion of HPLMN
determined free-format charging information to normal call records. This was agreed by MoU
CAGE2+ to be 40 bytes per call record !
-Support of additional charging relevant information to the CSE. On request the visisted MSC shall
report call duration and release cause back to the HPLMN CSE.
-Control of call duration using maximum duration timers that run in the MSC. This is thought to be
more reliable than purely CSE based call duration limits.
Combination of almost all the mentioned mechanisms is possible.
32
CAMEL phase 2 - New Features (2)
Support of GSM Supplementary Service invocation
notification to the CSE
Subscriber Interaction with the CSE by using USSD
Support of short forwarded-to numbers
Improved efficiency due to criteria for contact with CSE
for MO and MT
Support of Follow-on calls
Cell Id as part of the Location information
Alerting patterns controlled by the CSE
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33
4. Improved Exception Handling in case of unsuccessful call attempts
-Report of abandon, busy and not reachable event to the CSE. This feature is of very high interest (1)
for services like Call Hunting services and Personal Number
5. Support of GSM Supplementary Service (ECT, CD, MPTY) invocation notification to the
CSE
6. Improved efficiency due to criteria for contact with CSE MO and MT (trigger detection
points): More efficient signalling, screening functions, support of VPN.
For terminating calls the criteria are limited to the the type of basic service. This feature was
considered not a service relevant feature but rather a matter of network efficiency.
7. Support of short forwarded-to numbers. This feature would allow a SPNP with short number to
be accepted also by the GSM call forwarding service. Interest is (2)
8. Cell Id as part of the Location information. Since the cell ID is of limited use for foreign
operators (usually the cell numbering plan is not know) the feature is of medium interest, but can be
used in the HPLMN.
9. Support of Follow-on calls: This capability was not a high priority from the start but was
perceived as a useful by-product as the SSF capabilities were needed for providing chargable
announcements after disconnect.
10. Alerting Patterns controlled by the CSE
GSM will support as part of the GSM release 97 different alerting patterns controlled by the network.
This will allow the user to associate different ringing tones to e.g. incoming USSD and CCBS calls.
With CAMEL it is proposed to change the alerting category by the CSE, so that for instance calls
from withing a VPN can be identified easily by the user.
33
Special Resources (1):
The principle
IP provides e.g.
announcements, speech
recognition, voicemail
functions
Different operational
scenarious in GSM:
–
–
–
–
–
gsmSCF
gsmSRF3) IP to SCP dialogue
1) Est. Temp. Connect
4) DisconnectFD
2) Traffic channel to IP
IP in the HPLMN
IP in the VPLMN
IP integrated with SSP
Standalone IP
IP access via assisting SSP
IIR Implementing Mobile IN services 8.12.97
CSE
IP
gsmSSF
MSC
CCF
MS
MSC/SSP
Example: Standalone IP
Stefan Aprath, PT SMG
34
gsmSRF:The specialized resource function provides a pool of resources for access by other network
entities. These resources include for example sending of announcements to the parties in a call,
prompt for information using DTMF sending and receiving, speech recognition, synthesized speech
provision, protocol conversion, specialized connection resources (e.g. audio conference bridge or
information distribution bridge) or voicemail.
IP: Intelligent Peripherial, physical node containing an SRF. The IP can also provide call handling
functions that are not standardized.
For CAMEL operating in the GSM environment, there are a number of considerations:
0) In CAMEL a subscriber shall have access to the SRF independent from his location, i.e. also when
roaming.
1) Operator’s need to design IP functionality (e.g. record announcements) in conjunction with OSS.
As a result, the SRF needs to be under the management of the home network and therefore mostly
located in the home network.
2) Most efficient handling (in terms of cost for signalling and traffic channel use) is however possible
with local SRFs, that are located close to the subscriber.
3) Networks may use centralized SRF to ease operation and maintenance, possibly with service
specific functions or decentralized SRFs with basic functions in all of them for loadsharing purposes.
4) If possible, the physical arrangements should be transparent for the service logic to keep the service
logic simple. There may also be restrictions at the international siganlling boundaries.
Those considerations are partially colliding and may result in a large number of scenarios, where
operators make use of bilateral agreements or even proprietory standards, if the SRF is located in the
home network. However, even for scanarios in the home network the interface between IP and SCP is
specified by CAP.
34
Special Resources (2):
Access Scenarios
SRF in HPLMN is
accessed from
VPLMN
Home Network
Bilateral agreement allows access to
SRFs in VPLMN.
Distributed SRFs
in VPLMN,
standalone or
integrated
gsmSRF
gsmSRF
CSE
gsmSCF
Centralized SRFs in
VPLMN
gsmSRF
gsmSSF
gsmSSF
gsmSRF
gsmSSF
gsmSSF
gsmSSF
Visited Network
MS
Stefan Aprath, PT SMG
IIR Implementing Mobile IN services 8.12.97
35
SRF Scenarios in ETSI INAP
Cases without assisting SSP
a) SSF Relay
b) Direct path SCP to IP
Optional
No
IP directly
connected to
initiating
SSP?
Yes
Yes
d) Assist without relay;
return control to initiating
SSP on completion of UI
No
No
SRF integrated
with initiating
SSP?
Signalling
procedure to
establish
connection to IP
ConnectToResource
EstablishTemporar
y
Connection
EstablishTemporar
y
Connection
Signalling to SRF
Via initiating SSP
Direct to IP
Direct to IP
Cases with assisting SSP
c) Assist with relay; return
control to initiating SSP on
completion of UI
e) Handoff; retain control at
assisting SSP after UI
completed
Signalling Procedure
to Establish
Connection to
Assisting SSP
EstablishTemporary
Connection
Signalling
procedure to
establish
connection to IP
ConnectToResource
Signalling to SRF
Connect
ConnectToResource
Via assisting SSP
Via assisting SSP
35
Special Resources (3):
Considerations for CAMEL
Access to the SRF independent from subscriber’s
location
Design IP functionality in conjunction with OSS
Minimize Internetwork signalling and traffic costs
Physical arrangements transparent for the service
logic
Some IN scenarios excluded for CAMEL
CAP interface between SCF and SRF specified
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Stefan Aprath, PT SMG
36
Out of the scenarios defined by ETSI INAP CS-1 only some are supported inCAMEL. Priorities
were seen in the ability to route the call back to an IP located in the HPLMN for OSS dependent
special resources. In addition to the options shown on the slide before, network operators may also
agree to deploy regional SRFs to the visited PLMNs that are operated by the HPLMN :
a) SSF relay: The SRF is either integrated or in an directly attached IP. All operations are relayed.
This scenario is the most efficient if bilateral agreements exist and integrated SSP/IP solutions prevail.
This scenario depends on the capability of the SSP in the visited network and is therefore not
universal.
b) Supported in CAMEL
c) Supported in CAMEL. There is the need to send acorrelation from the SCP via the SSP to the
assisting SSP in order to allow the latter to contact the SCP.
d) If the HPLMN operator uses option c,d in his HPLMN, there is no need to change the procedure for
the roaming case.
e) Hand-off feature is not supported, I.e. the control will always be returned to the initiating SSF.
36
Subscriber interaction with
CSE by using USSD
HLR
CAMEL
USSD
application
Analyse the
service code
against e.g.
user specific
USSD
information
and general
USSD
information
IIR Implementing Mobile IN services 8.12.97
USSD Handler
USSD
Handler
CSE
MAP
gsmSCF
MAP
*#142*CSE_SERVICE#
VLR
MSC
Home Network
Stefan Aprath, PT SMG
MS
Visited Network
37
User Interaction with the CSE via USSD
USSD: Unstructured Supplementary Services Data
The support of this function is a network operator option in GSM. The HLR acts as a transparent
relay.
There is already a mechanism in GSM that routes USSD messages to the HLR depending on the
service code.
E.g. 1, 2 or 3 digits from the set (*, #) followed by 1X(Y), where X=any number 0-4, Y=any number
0-9, then, optionally "* followed by any number of any characters", and concluding with # SEND.
xy is the service code. The service code may be further analysed by the HLR and relayed to the gsm
SCF if appropriate.
The relay is likely to be controled by the USSD CAMEL subscription information (U-CSI ): U-CSI
stores per subscriber the service code and an SCF address to which it should be relayed.
The relay can also be controlled by a general USSD subscription information that is not stored per
subscriber.
SMG studies currently the enhancement of the USSD service with regard to the SIM Toolkit. See
below in this presentatin.
37
GSM AoC SS: Service
with deficiencies
Administration
MSC
(e1, .., e7)
(e1..e7)
MS
SIM
CONFIRM
Calculate
charge
VLR
HLR
Release, if
prepaid
used up
Subscriber
=AoC(C)
administration at each MSC
only one tariff model for everybody
-> no service provider specific tariffs
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38
An important improvement: Advice of Charge (AoC)
How does it work in GSM and why is it not very successful ?
The AoC service is a typical example of a service that fails to fulfill the user and service providers
requirements because it is based on the switching and mobility managing architecture, i.e. HLR and
MSC. In this case the HLR contains information whether a subscriber has subscribed to the AoC
service (and whether the charging information is only for information or for charging). This
information is transported to the serving network, where tables of tariff information (including tariff
switching times and initial charging is administered: the so called e-parameters, see GSM 02.24). The
MSC makes sure that the MS supports the feature and transmits the e-parameters to the MS.
The MS with some functions on the SIM performs the calculations in order to charge the call correctly
and will terminate a call if that the pre-set charge limit is exceeded. The prepaid charge is set by the
use of a PIN2, which is unknown to the subscriber. The MS can display the charging information
during and at the end of the call.
The disadvantage of this scheme is obvious: All customers served by a specific MSC are subject to the
same charging, regardless of whether they are roaming or to which ServiceProvider they belong.
Moreover, the service can not be used together with some call forwarding services, which generate a
charge for the subscriber without involving him in the call. This renders the service almost useless
except for very special cases where the network operator offers the service directly as part of a
standard tariff.
38
Vivat AoC! CSE control of
e-parameters
Administration
CSE
Subscriber=
(e1, .., e7)
However: This does not work
for incoming calls when
roaming !
gsmSSF
HLR
Subscriber
=AoC(C),
CSI
(e1..e7)
MS
SIM
MSC
CONFIRM
VLR
Calculate
charge
gsmSSF
Release, if
prepaid
used up
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39
AoC support by CAMEL:
In this scenario, the subscription information is still retained by the HLR, but the subscriber is at the
same time a CAMEL subscriber. If an outgoing call is setup, the MSC will via the gsmSSF contact the
CSE and obtain charging information in form of the e-parameters. The SCE can however determine
the e-parameters time and subscriber/ service provider dependent. By sending the e-parameters via the
MSC to the subscriber’s MS, the AoC service from the subscriber perspective is the same.
The procedure used for this are the SendChargingInformation, containing e-parameters and, if a tariff
switch occurs, the tariff switch time with a second set of e-paramters.
There is the possibility to use only the AoC information SS, which will transfer the e-parameters, but
not supervise the call duration. That function could be performed by the CSE as part of the service
logic.
To summarize, the AoC service has gained substantial improvements and can be reconsidered by
operators to be offered as a convenient on-line charging tool.
The reason for the HLR still being used for the AoC provision is the special service integrity
requirement. The HLR has mechanisms in place that will not allow roamin if the service is not
supported somewhere.
Due to the fact that theterminating CAMEL service is handled in the IPLMN, AoC does not work for
terminating calls - and terminating calls are charged for in the case of roaming ! This shortcoming
could be addressed at a later phase of CAMEL.
39
CAMEL Call Duration Control
Tariff 2
TS23
T3
call released
report time TS23
IIR Implementing Mobile IN services 8.12.97
call answered
TS22
T2
TS21
portion 3
grant call portion 2
T1
TS12
CSE
report time TS22
portion 2
grant call portion 2
portion 1
report time TS12 and TS21
TS2
Tariff 1
call set-up
grant call portion 1 (T1) and time until Tariff 2 (TS2)
Stefan Aprath, PT SMG
40
Example:
1.The call is answered, tariff 1 applies
2. CSE is contacted, timestamp is provided
3. CSE allows call to progress and sends granted call portion time T1 and time until next
tariff switch applies, TS2
4. The called party answers.
5. Tariff switch occurs (if e-parameters are provided, a new set is sent to the subscriber)
6. Call portion 1 ends. Time elapsed from answer to tariff switch TS12 and since tariff switch
is reported to the CSE.
7. CSE decides that there is some credit left and grants call portion 2.
etc.
40
A Fraud control feature:
SS Invocation Notification
SS Invocation Notification is applicable to
–
Call Deflection, MultiParty and Explicit Call Transfer
SS-CSI is transported from the HLR to VLR on
Location Update
CSE is contacted by the MSC if criteria in SS-CSI
match
–
–
For notification only there is no CAMEL handling of
outgoing/incoming calls
No suspend of Supplementary Service invocation
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41
Notification of SS invocation
The SMG security group (SMG10) determined that a number of the new supplementary services bear
a high risk for fraud because they potentially allow the establishment of parallel calls for which a
single subscriber is to be charged. Therefore within the framework of CAMEL phase 2 a mechanism
is introduced to notify a CSE about invocation of such services: Call Deflection, Explicit Call Transfer
and Multiparty Service. The service is however supported using a new MAP interface between the
MSC and the gsmSCF. The subscriber related information (called SS-CSI) is stored in the HLR and
send to the VLR along with the other subscription data. This data contains information indicating for
which supplementary services notifications shall be sent, and the address of the gsmSCF to which the
notification shall be sent. If a subscriber is marked with SS-CSI a notification is sent to the gsmSCF.
The processing of the particular SS invocation is not suspended and is independent of the invocation
of call related CAMEL processing, i.e. processing indicated by O/T-CSI.
The benefits of this solution is simplicity. It allows also special CSEs for the control of fraud.
41
SS Invocation Notification:
The Principle
Administration
CSE
MS
gsmSSF
MS
MAP Notify SS (ECT)
Invoke ECT
5SEND
HLR
MS
SS-CSI
MSC
VLR
MAP LU Dialogue
IIR Implementing Mobile IN services 8.12.97
SS-CSI
Stefan Aprath, PT SMG
42
SS-CSI: Supplementary Service Camel Subscription Information
LU: Location Update
ECT: Explicit Call Transfer
42
Part 1: The GSM vehicle to Operator
Specific Services: CAMEL
Part 2: CAMEL between GSM and IN
Part 3: CAMEL phase 1 & 2: Features
Part 4: On CAMEL’s back into the future
IIR Implementing Mobile IN services 8.12.97
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43
43
Implementing CAMEL - Outline (1)
CAMEL phase 1 and even more phase 2 will be used to
extend IN services currently offered only within the
HPLMN to roaming customers.
Today: The following services are offered by some GSM
operators in Europe based on operator specific IN solutions:
Mobile Virtual Private Network
Virtual PBX
Personal Number, Automatic call forwarding (mobile - fixed)
Homecall
Prepaid Card
Hotbilling
Call Screening
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44
44
Implementing CAMEL - Outline (2)
“As soon as possible”
Mid 1998: CAMEL
phase 1, though being
very limited, will be
used to offer:
Mid 1999: CAMEL
phase 2 will allow most
existing services to be
offered abroad:
Short numbering,
subset of MVPN
Call Screening
Enhanced Call
Forwarding (time and
location dependent)
IIR Implementing Mobile IN services 8.12.97
Stefan Aprath, PT SMG
Prepaid Card Service
with AoC(I)
Support of Private
Numbering Plan
Flexible charging
Freephone, Universal
number
45
45
Ongoing work in GSM
possibly based on CAMEL
CAMEL is intended to also be the basis for standardized
GSM services, e.g.
Support of private Numbering Plan
Mobile Access Hunting
Number Portability
Emergency Calls and Location Services
Further, it can complement new features like:
The SIM Toolkit/The Mobile Station Application Execution
Environment
Shared Data Interworking Function
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46
The SIM Toolkit/The Mobile Station Application Execution Environment
The above mentioned workitems in SMG are both related to applications that are located and
performed at the subscriber's equipment, i.e. the Mobile Station including the SIM card. Many
services, especially internet based ones, can be handled and controlled more efficiently on a client server based communication between the network and the terminal. The CAMEL service environment
however could become an architecural component, since it has the capability to communicate with the
terminal via USSD and can at the same time control at least the circuit switched services of the
subscriber. USSD is currently enhanced to send instructions directly to the SIM card and transparent
to the user (analogue to existing SM capabillity). The SIM toolkit application would then allow e.g. to
associate soft buttons with certain USSD strings which in turn invok CAMEL based services.
Support of Private Numbering Plan
This feature can to a large extent be supported by CAMEL phase 2. In CAMEL phase2 some
measures were taken to allow also the registration of short call forwarding numbers.
Emergency Calls and Location Services
Due the requirement mainly coming from the North American market (Regulator require location of
wireless subscriber within 125m 67% of time), a solution making use of CAMEL is under study.
46
Has CAMEL a role in
GSM Phase 3 ?
Internet
TCP/IP
USSD / SMS
CSE
HLR
gsmSSF
SIWF/ SGSN
ccData, HSCSD
USSD / SMS
MSC
GGSN
Multimedia Phone
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47
For discussion:
47
CAMEL
looks ahead to its 3rd Phase (1)
What is not there yet, but operators are likely to
want:
Flexible call leg management: CS-2 Call Party Handling
More efficiency by loadsharing and specialized CSEs
New Fraud control features
Improved Interworking with GSM supplementary service
Support of Mobile Specific Trigger Points
SMS MO, MT
Location update
Improved Location Service: Forced location update
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48
48
CAMEL
looks ahead to its 3rd Phase (2)
The project outline:
–
12/97 Prestudy of wanted features
Collection of options
Prioritisation
–
03/98 Kick-off joint SMG1-SMG3
–
06/98 Delivery of Stage 1 specification
12/98 Delivery of Stage 2, 3 specifications
Final feature package for CAMEL phase 3
–
IIR Implementing Mobile IN services 8.12.97
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49
Overview of CAMEL phase 1, phase 2 and candidate phase 3 Features
Protocol Operations:
Trigger Detection
points:
Trigger criteria
INCS1
29
CAMEL phase 1
CAMEL phase 2
? CAMEL phase 3 ?
7 CAP
1 MAP
2
22 CAP
3 MAP
2
Triggering on all events
O-CSI, T-CSI
+U-CSI, G-CSI, SSSCI
+Trigger criteria MO
and MT
One CSE per
subscriber
Call related Detection
Points
Call unrelated
Detection Points
Specialized
Resources
Fraud control
Call unrelated CSE
interaction
Call related CSE
interaction
Interworking with
other GSM services
+ criteria for multiple CSE per
subscriber and per trigger detection
point
+ service interaction of multiple CSEs
MO: 3 MT: 3
MO: 8 MT: 7
+ Midcall Trigger (Notification on User
+Calling party abandon initiated call dependent SS)
+no answer
+not reachable
+busy
+routeSelectFailure
+ Location Update
+ Network Attach/Detach
+ Notification on User initiated call
independent SS)
+ Notificatin on SMS (MO, MT)
+ some Assist
procedures
+ support of Special
+text to speech conversion
Resource Function
+ Downloading thresholds on number
+ SS Invocation
notification (MPTY, CT, of call independent supplementary
service operations by a user.
CD)
+Detection and control of user
+ Support of USSD
+ Any time
initiated supplementary services
+Cell Id in
interrogation
management
geographical data
+Geographical
data
+ Detection and control of mobile
originated and terminated SMS,
+ Subscriber state
processing of SMS at CSE
+ Charging of call unrelated user
interactions
+ CSE controlled and initiated
Location Update
+ Charging procedures + CS-2 Call Party Handling
+ Call Setup
+ CSE controlled AoC for terminating
+ Suppression of
+ Support of online
charging using AoC
calls -> Introduction of IN handling at
Announcements
served MSC. (however: multiple point
and tones for MT + Follow-on call
of control and service interaction
calls
+Support of
considerations) or MAP solution.
+CSE initiated calls
CalledPartyBCD
+ Suppression of GSM SS per call
number
+Geographical
data
HSCSD
GPRS
ASCI
SOR
49
Success of GSM
is opportunity for CAMEL
The Role of the GSM MoU:
–
–
A community of mutual trust: Indispensible for
OSS, that put a burden on the VPLMN
Joint effort: GSM MoU has declared
CAMEL phase 1 an essential service and encourages
deployment by all GSM operators End of 1999
CAMEL phase 2 an essential service and encourages
deployment by all GSM operators End of 1999
Success of CAMEL is coupled to the success
of GSM
IIR Implementing Mobile IN services 8.12.97
Stefan Aprath, PT SMG
50
50
.. and GSM is successful:
–
–
–
Expected 55 million subscribers (by end of 1997)
More than 203 networks on air
more than 100 million calls/month originated by roamers in
visited networks.
With especially prepaid services taking off in the mass
market, 20% CAMEL subscribers is in reach.
IIR Implementing Mobile IN services 8.12.97
Stefan Aprath, PT SMG
51
All GSM operators have international roaming. The advanced operators
have 80 or more roaming relations working. Every new operator has
typically after 6 month of operation at least 10 roaming relations in
operation. In total several thousand roaming agreements are concluded and
roaming is in operation.
The roaming traffic exceeds the expectations. At the end of 96 there were
more than 100 million calls/month originated by roamers in visited
networks. Many networks have 10% and more of their traffic from roamers
Source: ETSI SMG
51
Some Statistics…..
350
300
250
200
150
100
50
0
EoY 1992
1994
Source: ETSI SMG
IIR Implementing Mobile IN services 8.12.97
1996
1998
2000
2002
Countries with GSM
Networks on air
Subscribers [million]
Stefan Aprath, PT SMG
52
52
Thank you for your
attention !
Questions ?
IIR Implementing Mobile IN services 8.12.97
Stefan Aprath, PT SMG
53
Acknowledgement:
The information contained in this presentation is the result of the joint effort of SMG, SMG1, SMG3
WPC and the creators of IN in ETSI and ITU.
Some of the illustrations used in this presentation are copyright of the European Telecommunication
Standardization Institute.
Sources:
GSM 10.78 Project plan for CAMEL phase 2,
GSM 09.02 MAP
GSM 03.18 GSM Basic Call Handling
GSM 02.78, GSM 03.78, GSM 09.78 Digital cellular telecommunications system (Phase 2+); Customized
Applications for Mobile network Enhanced Logic (CAMEL) - Stage 1, 2, 3
ITU-T Q.1219
DRAFT EN Intelligent Network (IN); Intelligent Network Capability Set 1 Extension; Intelligent Network
Application Protocol (INAP); Part 1: Protocol specification for Camel Phase 1
DRAFT EN Intelligent Network (IN); Intelligent Network Capability Set 1 Extension; Intelligent Network
Application Protocol (INAP); Part 2: Protocol Implementation Conformance Statement (PICS) proforma
specification for Service Switching Function (SSF) for Camel Phase 1
GSM 03.32 Digital cellular telecommunications system (Phase 2+); Universal Geographical Area
Description (GAD)
ETS 300 374-1 ETSI Core Intelligent Network Application Protocol (INAP), Part 1
…and Various internet pages
53
Protocol Operations in CAMEL (ASEs)
No. ETSI Core INAP CS-1 operation
Function
Applicability
CAMEL CAMEL
phase 1 phase 2
gsmSSF gsmSCF X
X
gsmSRF gsmSCF
X
X
X
Setup connect ot the
X
IP
X
gsmSCF gsmSSF X
gsmSCF gsmSSF X
X
gsmSSF gsmSCF X
X
gsmSCF gsmSSF X
X
1
2
3
4
5
initialDP
assistRequestInstructions
establishTemporaryConnection
disconnectForwardConnection
connectToResource
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
connect
releaseCall
eventReportBCSM
requestReportBCSMEvent
eventNotificationCharging
requestNotificationChargingEvent
collectInformation
continue
initiateCallAttempt
resetTimer
furnishChargingInformation
applyChargingReport
applyCharging
callGap
serviceFilteringResponse
activateServiceFiltering
callInformationReport
callInformationRequest
sendChargingInformation
specializedResourceReport
playAnnouncement
Play announcement
promptAndCollectUserInformation
cancel
activityTest
1
2
3
AnyTimeInterrogation
Unstructured SS Request
Unstructured SS Notify
Direction
gsmSCF
gsmSSF X
X
X
X
X
X
gsmSCF
gsmSSF X
X
X
X
X
X
X
X
X
gsmSCF
gsmSCF
gsmSCF
HLR
HLR
HLR
X
X
gsmSRF –> gsmSCF
gsmSCF gsmSRF
X
54
Detection Points In CAMEL
CAMEL Detection
Point:
DP2 Collected_Info
DP 4
Route_Select_Failure
DP 5 O_Busy
DP6 O_No_Answer
DP7 O_Answer
DP9 O_Disconnect
DP 10 O_Abandon
DP x1
O_Not_Reachable
Description:
Indication that the O-CSI is analysed.
Indication that the call establishment
failed
Indication that a busy indication is
received from the terminating party
Indication that an application timer
associated with the O_No_Answer DP
expires
Indication that the call is accepted and
answered by the terminating party.
A disconnect indication is received from
the originating party or from the
terminating party.
Indication that a disconnect indication is
received from the originating party
during the call establishment procedure
Not reachable event can be determined
upon a cause IE in the ISUP release
message.
DP12
Indication that the T-CSI is analysed.
Terminating_Attempt_
Authorised
DP 13 T_Busy
Indication that a busy indication is
received from the destination exchange
DP 14 T_No_Answer Indication that an application timer
associated with the T_No_Answer DP
expires
DP15 T_Answer
Call is accepted and answered by
terminating party
DP17 T_Disconnect
DP 18 T_Abandon
DP x2
T_Not_Reachable
DP Type
Applic
ability
TDP-R
EDP-N, EDP-R
CAMEL CAMEL
phase 1 phase 2
X
X
X
EDP-N, EDP-R
X
EDP-N, EDP-R
X
EDP-N, EDP-R
X
X
EDP-N, EDP-R
X
X
EDP-N
X
EDP-N, EDP-R
X
TDP-R
X
X
EDP-N, EDP-R
X
EDP-N, EDP-R
X
EDP-N, EDP-R
X
X
A disconnect indication is received from EDP-N, EDP-R
the originating party or from the
originating party.
A disconnect indication is received from EDP-N
the terminating party during the call
establishment procedure
Not reachable event can be determined EDP-N, EDP-R
from the HLR or upon a cause IE in the
ISUP release message.
X
X
X
X
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