Transcript deng

Customized Applications for
Mobile Network Enhanced Logic
(CAMEL)
Zhaohui Deng
Yinyan Zhou
1
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
2
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
3
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
4
Evolution of Wireless Intelligent Network
(Cnt)


Advanced Intelligent Network: provide serviceindependent 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
5
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
6
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
7
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
8
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
9
Service Drivers for WIN Phase II

Prepaid Charging(PPC)



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


Should be invoked before any other service to verify the
balance
Advice of charging; inform cost of impending call
Call management service

Rejection of undesired annoying call
10
Example of WIN phase II
Free Phone
Serving System
IP
SCP
MSC
MS origination
ANLYZD[TRIGTYPE, DGTSDIAL, TRANSCAP, WINCAP]
SEIZED[SRFCapability, PLIND]
Seizes[TLDN]
CONNRES[DSTDGT,CARDGTS,ROUTDGTS]
TLDNAT
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.
INSTREQ[ ]
SRFDIR[ANNLIST
PLAY ANNOUNCEMENT
srfdir[]
anlyzd[TERMLIST, DMH_SVCIDLIST, BILLDGTS]
instreq[ ]
Release message
Call setup
11
Service Drivers for WIN Phase III

Location-Based Service
12
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 Environment
MAP: Mobile Application Part, protocol that interconnects wireless telephone system
13
Example of CAMEL phase I
MS Originating CAMEL call
MS
MSC/VLR
+
gmsSSF
A
C
gsmSCF
PSTN
CAP-initialDP
CAP-Connect
B
ISUP-IAM
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’s
Category, 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
14
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 Function
VRU: Voice Response Unit
USSD: Unstructured Supplementary Service Data
15
CAMEL Phase I Architecture
Home Network
MAP
HLR
gsmSCF
MAP
CAP
MAP
CAP
gsmSSF
GMSC
Interrogating Network
VLR
Roaming leg
gsmSSF
VMSC
Visiting Network
Dotted lines for signaling connection, continuous line present a voice connection
MAP: Mobile Application Part
GMSC: gateway MSC
CAP: CAMEL Application Protocol
VMSC: visiting MSC
16
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
17
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 – CSI
TIF-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
18
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 TCSI exists, indicating GMSC to request instructions
from gsmSSF for further execution
19
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 OCSI 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
20
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
21
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
22
CAMEL Phase I:
Originating Basic Call State Model
O-Null&Authorize_Origination
_Attempt_Collect-Info
DP2
O_Exception
Collect_Info
Analyze, Routing & Alerting
DP7
DP9
O-Disconnect
O_Answer
O_Active
23
Description of O-BCSM DPs in the MSC
CAMEL
Detection
Note:
BLUE
for
phase I
BLACK
is added
In phase
II
DP Type
DP2 Collected_Info
TDP-R
DP 4
Route_Select_Failur
e
DP 5 O_Busy
EDP-N, EDP-R
DP6 O_No_Answer
EDP-N, EDP-R
DP7 O_Answer
EDP-N, EDP-R
DP9 O_Disconnect
EDP-N, EDP-R
DP 10 O_Abandon
EDP-N
EDP-N, EDP-R
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, a not reachable event is
determined upon a cause IE in the
ISUP release message
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
establishm ent procedure
24
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)
N: Notification
R: request
DP7 encountered (EventReportBCSM)
DP9 encountered (EventReportBCSM)
Continue call processing (Continue)
25
CAMEL Phase I:
Terminating Basic Call State Model
T_Exception
T-Null
DP12 Terminating_Attempt_Authorized
Terminating Call Handling
DP15
DP17
T-Disconnect
T_Answer
T_Active
26
Description of T-BCSM DPs in the GMSC
CAMEL
DP Type
Detection Point:
Description:
DP12
Terminating_Atte
mpt_Authorised
DP 13 T_Busy
TDP-R
Indication that the T-CSI is analysed.
EDP-N,
EDP-R
DP 14
T_No_Answer
EDP-N,
EDP-R
DP15 T_Answer
EDP-N,
EDP-R
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.
Indication that an application timer
associated with the T_No_Answer DP
expires
Call is accepted and answered by
terminating party
A disconnect indication is received from the
terminating party or from the originating
party.
A disconnect indication is received from the
originating party during the call
establishment procedure
DP17
T_Disconnect
DP 18
T_Abandon
EDP-N
27
CAMEL Phase II Architecture
Home Network
MAP
HLR
MAP
CAP
gsmSCF
MAP
GMSC
Roaming leg
gsmSSF
MS
MSC
MO call - Outgoing leg
(or Forwarding leg)
Forwarded leg
Interrogating Network
CAP
VLR
gsmSSF
Incoming line
MAP
CAP
gsmSRF
Visiting Network
Home/Interrogating/Visiting Network
28
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
29
CAMEL Phase II:
Originating Basic Call State Model
A
DP10
O_Null & Authorise_Origination_
Attempt_Collect_Info
O_Exception
O_Abandon
DP2
Collected_Info
Route_Select_
Failure
Analyse, Routing
& Alerting
O_No_Answer
DP5
DP6
A
DP7
O_Answer
DP9
O_Busy
DP4
O_Active
O_Disconnect
DP explanation
Please refer to former slide
Basic Call transition
Transition beyond Basic Call
30
CAMEL Phase II:
Terminating Basic Call State Model
A
T_Exception
T_Null
DP18
T_Abandon
DP12
Terminating_Attempt_Authorised
T_Busy
Terminating Call Handling
T_No_Answer
DP13
DP14
A
T_Disconnect
T_Answer
DP17
DP15
T_Active
DP explanation
Please refer to former slide
Basic Call transition
Transition beyond Basic Call
31
Terminating Call Example, Phase II
gsmSCF
MSC
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)
Continue call processing (Continue)
32
An example of Virtual Private Network in
a visited network using CAMEL
33
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
34
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 Bnumber for international routing and transfers the information
to the MSC in the visited network, which resumes the set-up
process.
35
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
36