1 customized applications for mobile network enhanced logic (camel) zhaohui deng yinyan zhou
TRANSCRIPT
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Customized Applications for Mobile Network Enhanced
Logic(CAMEL)
Zhaohui DengYinyan Zhou
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What Is CAMEL CAMEL is the wireless intelligent network
standard for GSM networks CAMEL is not a separate service but a new
feature ( It is a tool to help the network operator to provide the subscribers with OSS even when roaming outside the HPLMN)
In North America the corresponding standard is WIN
WIN and CAMEL use almost the same Intelligent Network Conceptual Model
OSS: Operator Specific Services HPLMN: Home Public Land Mobile Network
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Evolution of Wireless Intelligent Network
Switchboard: Operator manually intervene with an intelligent routing decision
Automatic Switching: hard-wired service logic, dependent on switching vendor for all aspects of service logic necessary to deploy new features, equipment from different vendors made it hard for ubiquitous service deployment
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Evolution of Wireless Intelligent Network (Cnt)
Stored Program Control: programmable service logic, but not modular. New service introduction is hard due to dependency between service and service specific logic associated with that service. Service logic used for one service could not be used for another
Common Channel Signaling: mid-1970s. Out-band signaling vs. in-band signaling path
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Evolution of Wireless Intelligent Network (Cnt)
Advanced Intelligent Network: provide service-independent service logic and service management, facilitate independent service development capability
WIN and CAMEL: standardized capabilities in conjunction with SS7 signaling, provide network intelligence efficiently and seamlessly in wireless networks
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Driver for CAMEL Emerging
Prior to CAMEL, GSM has INAP as protocol injecting intelligence into GSM network. INAP designed for wireline networks, no mobility management.
CAMEL: standard to provide wireless intelligent network capabilities for development, deployment and operation of enhanced mobile communications service and roaming across different vendor switches
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WIN BCSM DP Example
Originating BCSM detection Points: Origination_attempt_Authorized DP – A point in
the call ( such as an authorized customers initiates a call) when an external element is queried prior to the calling party dialing digits. Can be used for service such as voice activated dialing.
Analyzed_Information DP: for Incoming call screening at customer’s home MSC????
Collected_information DP: used for providing service to calling party such as Call forwarding
BCSM: basic call state model
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WIN BCSM DP Example
Terminating BCSM Detection Points:
Facility_Selected-and_Available DP: calling name service to customer
T_Busy and T_No_Answer DP: for routing call to a voice message system or special announcements/tones
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Service Drivers for WIN Phase I
Calling Name Presentation (CNAP) Voice Controlled Service (VCS)
Such as basic voice controlled dialing VCS with voice authentication, speech –to-text
conversion,etc Incoming Call Screening (ICS)
Answer, don’t answer, redirect
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Service Drivers for WIN Phase II
Prepaid Charging(PPC) Should be invoked before any other service to verify the
balance Preferred Language Support Free Phone
Launch AnalyzedInformation message to SCP, seize IP to set up ConnectionResource message to MSC to connect to IP and IP play announcement to direct how to make the call, completely toll free and mobile airtime free
Billing Service Capabilities Advice of charging; inform cost of impending call
Call management service Rejection of undesired annoying call
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Example of WIN phase IIFree Phone
IP SCP MSC
Serving System
MS originationANLYZD[TRIGTYPE, DGTSDIAL, TRANSCAP, WINCAP]
SEIZED[SRFCapability, PLIND]
Seizes[TLDN]CONNRES[DSTDGT,CARDGTS,ROUTDGTS]
TLDNAT call setup
INSTREQ[ ]
SRFDIR[ANNLIST
PLAY ANNOUNCEMENT
srfdir[]
anlyzd[TERMLIST, DMH_SVCIDLIST, BILLDGTS]
Release messageinstreq[ ]
Call setup
MSC upon recognizing a FreePhone call attempt, launched a Analyzed Information(ANLYZD) message to SCP. The SCP getting the request, seizes the IP resource and IP send Connect Resource(CONNRES) message to the MSC, directing it to set up a connection to IP. IP plays an announcement to the caller(relative to the FreePhone number called)Upon listening to the announcement, a a series of release messages are played prior to the MSC setting the call up to the appropriate telephone number associated with FreePhone number.
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Service Drivers for WIN Phase III
Location-Based Service
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Phased Development of Standards – CAMEL Phase I
Introduce basic INAP capabilities such as support of initial DP message
Basic call set-up reporting capabilities: inform CSE of mobile origination and termination status, call-related CSE interactions
Suppress announcement tones at the serving system during call termination, allowing the home system to play announcements in native language of the home system
Offer Any Time Interrogation (ATI) message, a GSM MAP message: interrogate HLR to derive info about specific customer’s location and status
CSE: CAMEL Service EnvironmentMAP: Mobile Application Part, protocol that interconnects wireless telephone system
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Example of CAMEL phase IMS Originating CAMEL call
MSC/VLR +gmsSSF
gsmSCF PSTN
A B
C
A: MSC gets CAEML service info from VLR during the call setup of a MS, gmsSSF in the visiting network send the InitialDP message to gsmSCF and suspend the call processing. The InitialDP message contains service key, called and calling party number, calling party’sCategory, location number, bearer capability, event type BCSM, location and IMSI. After the service logic processing, B gsmSCF can for example do number translation, a CAMEL-specific Service logic is initiated from gsmSCF C MSC uses the information received to set up a call
MS
CAP-initialDP
CAP-Connect
ISUP-IAM
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Phased Development of Standards – CAMEL Phase II
Most significant enhancement over phase I is to support SRF, would allow user interaction with a VRU within CSE
Provide additional GSM MAP related improvements including support of USSD, another user interaction capability enhancement, this call-unrelated CSE interaction capability allows the subscriber to invoke CAMEL-based service via USSD commands.
Online charge indication via the Advice of Charge( AoC) feature for mobile originated calls. AoC is call-related CSE interaction that can be very useful when deployed in conjunction with services such as a Free Phone, prepaid and premium calling services.
SRF: Specialized Resource FunctionVRU: Voice Response Unit USSD: Unstructured Supplementary Service Data
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CAMEL Phase I Architecture
HLR gsmSCF
GMSC
gsmSSF
VMSC
gsmSSFVLR
MAP
MAPMAP
CAP
CAP
Roaming leg
Home Network
Interrogating NetworkVisiting Network
Dotted lines for signaling connection, continuous line present a voice connectionMAP: Mobile Application Part GMSC: gateway MSCCAP: CAMEL Application Protocol VMSC: visiting MSC
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CAMEL Phase I Architecture
Home Network present home PLMN (public land mobile
network) of CAMEL subscriber Home Location Register (HLR) and GSM
Service Control Function are the network elements involved in CAMEL
HLR stores for subscriber requiring CAMEL support information regarding O-CSI, T-CSI, TIF-CSI, U-CSI and SS-CSI
O-CSI, SS-CSI are sent to VLR in case of location update or O-CSI, SS-CSI update
U-CSI: USSD-CSI SS-CSI: Supplementary Service_CSI
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CAMEL Phase I Architecture
Home Network O/T-CSI is sent to GMSC when HLR responds to a
request for routing information
TIF-CSI, U-CSI and UG-CSI are stored in HLR only.
HLR may provide an interface towards gsmSCF for Any Time Interrogation
SS-CSI: Supplementary Service – CSITIF-CSI: translation information flag – CSI, subscriber data
indicate that when subscriber register a forward-to number, that HLR shall not attempt to perform any translation, number format check, (Forward To Number) FTN check, call barring check
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CAMEL Phase I Architecture Interrogating Network
Perform the interrogation of the home network for information on treatment of terminating CAMEL calls
Calling party of the terminating CAMEL call resides in the interrogating network and the called party resides in the visiting network.
Gateway MSC (GMSC) and gsmSSF are the entities handling of terminating CAMEL calls
When processing the calls for subscriber requiring CAMEL support, GMSC receive O/T-CSI from HLR. If T-CSI exists, indicating GMSC to request instructions from gsmSSF for further execution
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CAMEL Phase I Architecture Visiting Network
It is PLMN where the CAMEL subscriber is roaming. Involve handling of originating and forwarded
CAMEL calls May request for location information and status of
the subscriber Set up calls from and towards the visiting
subscriber, while handling the originating calls, VMSC detects if O-CSI exists, if does, then initial contact to gsmSCF take place
When roaming to a visiting network which doesn’t support CAMEL, home network handle the roaming
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Relationship
HLR-VLR interface: send CAMEL related subscriber data to VPLMN and provision of Mobile Station Roaming Number (MRSN), retrieve subscriber status and location, or to suppression of announcement for CAMEL service
GMSC-HLR interface: used at terminating calls to exchange routing information, subscriber status and location, suppression of announcement
GMSC-gsmSSF interface: internal interface, make it easy for handling DPs
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Relationship
gsmSSF-gsmSCF interface: used for gsmSCF to send instruction to gsmSSF to play tones.announcements to the users.
gsmSCF-HLR interface: used by gsmSCF to request information from HLR
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CAMEL Phase I: Originating Basic Call State Model
DP9
O-Null&Authorize_Origination_Attempt_Collect-Info
O_Exception
DP2
DP7
Analyze, Routing & Alerting
Collect_Info
O_Answer
O_Active
O-Disconnect
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Description of O-BCSM DPs in the MSC
CAMEL Detection
DP Type Description:
DP2 Collected_Info TDP-R Indication that the O-CSI is analysed.
DP 4 Route_Select_Failure
EDP-N, EDP-R Indication that the call establishment failed
DP 5 O_Busy EDP-N, EDP-R Indication that:a busy indication is received from the terminating party, a not reachable event is determined upon a cause IE in the ISUP release message
DP6 O_No_Answer EDP-N, EDP-R Indication that an application timer associated with the O_No_Answer DP expires
DP7 O_Answer EDP-N, EDP-R Indication that the call is accepted and answered by the terminating party.
DP9 O_Disconnect EDP-N, EDP-R A disconnect indication is received from the originating party or from the terminating party.
DP 10 O_Abandon EDP-N Indication that a disconnect indication is received from the originating party during the call establishment procedure
Note:BLUEfor phase IBLACK is addedIn phase II
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Originating Call Example, Phase I
gsmSCF MSC
DP2 encountered (InitialDP)
Monitor DP7 (N)(REquesrReportBCSMEvent)
Monitor DP9 (R)(REquesrReportBCSMEvent)
Continue call processing (Continue)
Check connection (ActivityTest)
Answer to connection check(activityTest Response)
DP7 encountered (EventReportBCSM)
DP9 encountered (EventReportBCSM)
Continue call processing (Continue)
N: NotificationR: request
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DP17
T-Null T_Exception
DP12
DP15
Terminating Call Handling
Terminating_Attempt_Authorized
T_Answer
T_Active
T-Disconnect
CAMEL Phase I: Terminating Basic Call State Model
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Description of T-BCSM DPs in the GMSC
CAMEL Detection Point:
DP Type Description:
DP12 Terminating_Attempt_Authorised
TDP-R Indication that the T-CSI is analysed.
DP 13 T_Busy EDP-N, EDP-R
Indication that:a busy indication is received from the destination exchange, Not reachable or call establishment failure event is determined from the HLR response or upon a cause IE in the ISUP release message.
DP 14 T_No_Answer
EDP-N, EDP-R
Indication that an application timer associated with the T_No_Answer DP expires
DP15 T_Answer EDP-N, EDP-R
Call is accepted and answered by terminating party
DP17 T_Disconnect
EDP-N, EDP-R
A disconnect indication is received from the terminating party or from the originating party.
DP 18 T_Abandon
EDP-N A disconnect indication is received from the originating party during the call establishment procedure
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CAMEL Phase II Architecture
HLR
GMSC
gsmSCF
MSC
Forwarded leg
MS Incoming line
Visiting Network Interrogating Network
Home Network
gsmSSF VLR
Roaming leg
CAP CAP
MAP
MAP MAP
gsmSSF
gsmSRF Home/Interrogating/Visiting Network
CAP
MO call - Outgoing leg (or Forwarding leg)
MAP
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CAMEL Phase II Architecture and Relationship
Phase II is based on phase I architecture. The basic new component is the gsmSRF. It provides a pool of resources for access by other network entities
gsmSCF –gsmSRF interface: used by gsmSCF to instruct the gsmSRF to play tones/announcement to the users
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CAMEL Phase II: Originating Basic Call State Model
O_Null & Authorise_Origination_Attempt_Collect_Info
DP2
O_Exception
DP9
DP7
Collected_Info
O_Answer
Basic Call transition
Transition beyond Basic Call
DP4
DP5
DP6
O_Disconnect
O_Active
Route_Select_Failure
O_Busy
O_No_Answer
DP10
O_Abandon
& Alerting
Analyse, Routing
A
A
DP explanationPlease refer to former slide
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CAMEL Phase II: Terminating Basic Call State Model
T_Null
Terminating Call Handling
DP12
T_Exception
DP17 T_Active
DP15
Terminating_Attempt_Authorised
T_Answer
Basic Call transition
Transition beyond Basic Call
DP13
DP14
T_Busy
T_No_Answer
DP18
T_Abandon
T_Disconnect
A
A
DP explanationPlease refer to former slide
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gsmSCFMSC
DP12 encountered (InitialDP)
Monitor DP15 (N)(REquesrReportBCSMEvent)
Monitor DP17 (R)(REquesrReportBCSMEvent)
Continue call processing (Continue)
Check connection (ActivityTest)
Answer to connection check(activityTest Response)
DP15 encountered (EventReportBCSM)
DP17 encountered (EventReportBCSM)
Terminating Call Example, Phase II
Continue call processing (Continue)
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An example of Virtual Private Network in a visited network using CAMEL
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An example of VPN in a visited network using CAMEL(Cnt)
1. A subscriber who has a VPN service in his home network is "roaming" in a network abroad. To call a colleague at the home office, all he has to do is dialing
the colleague's four-digit extension number “4772”. The exchange (SSP/MSC) in the visited network classifies the
call as a "CSE event“. DP2 is encountered, this InitialDP message contains from VMSC to gsmSCF contains service key and other subscription information. The set-up
process is temporarily interrupted.
VPN: Virtual private networks
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An example of VPN in a visited network using CAMEL(Cnt)
2. gsmSCF in the home network ask VMSC to monitor the DP7 and DP9, then it translates the extension number into a B-number for international routing and transfers the information to the MSC in the visited network, which resumes the set-up process.
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Reference
3GPP TS 03.78: Customised Application for Mobile Network Enhanced Logic phase 2
3GPP TS 02.78: Service Definition Igor Faynberg, L. R. Gabuzda, T Jacobson, H.L Lu: The
development of the Wireless Intelligent Network and its Relation to the international Intelligent Network Standards
E. Geulen, J Hartmann: Open Service Provisioning in GSM – What do we gain with CAMEL
J Hartmann: The Alignment of IN and GSM Gerry Christensen etc. Wireless Intelligent Network