Basic call state model
Encyclopedia
In Intelligent Network
and CAMEL
switching, a BCSM is a Basic Call State Model
A fundamental concept for IN control is the basic call state model (BCSM). When a call is processed
by an exchange, the call goes through a number of pre-defined phases. These phases of the call are
described in the BCSM. The BCSM generally follows the ISUP signalling of a call
TODO: Expand to Ph2,3,4
Intelligent network
The Intelligent Network , is the standard network architecture specified in the . It is intended for fixed as well as mobile telecom networks...
and CAMEL
Customised Applications for Mobile networks Enhanced Logic
Customised Applications for Mobile networks Enhanced Logic, or CAMEL for short, is a set of standards designed to work on either a GSM core network or UMTS network. They allow an operator to define services over and above standard GSM services/UMTS services...
switching, a BCSM is a Basic Call State Model
Types
- O-BCSM (Originating BCSM)
- T-BCSM (Terminating BCSM)
A fundamental concept for IN control is the basic call state model (BCSM). When a call is processed
by an exchange, the call goes through a number of pre-defined phases. These phases of the call are
described in the BCSM. The BCSM generally follows the ISUP signalling of a call
State machine description
In the following IN BCSMs, bold Detection Points and Points In Call are also present in the CAMEL Ph1 subset.TODO: Expand to Ph2,3,4
Points in call
- 1. O_Null & Authorize Origination Attempt
- 2. Collect_info (Merged with 1. in CAMEL Ph1)
- 3. Analyze_Info
- 4. Routing & Alerting (Merged with 3. in CAMEL Ph1)
- 5. O_Active
- 6. O_Exception
Detection Points
- 1 Origination_Attempt_Authorized
- 2 Collected_Info
- 3 Analyzed_Info (this is the only Statically armed DP, others are dynamically armed using "Request Report BCSM (RRBE)" message by the SCP)
- 4 Route_Select_Failure
- 5 O_Called_Party_Busy
- 6 O_No_Answer
- 7 O_Answer
- 8 O_Mid_Call
- 9 O_Disconnect
- 10 O_Abandon
Points in call
- 7. T_Null & Authorize Termination_Attempt
- 8. Select_Facility & Present_Call
- 9. T_Alerting (Merged with 8. in CAMEL Ph1)
- 10. T_Active
- 11. T_Exception
Detection Points
- 12 Termination_Attempt_Authorized
- 13 T_Called_Party_Busy
- 14 T_No_Answer
- 15 T_Answer
- 16 T_Mid_Call
- 17 T_Disconnect
- 18 T_Abandon
Messages
- Initial Detection Point (IDP)
- RRB (Request Report BCSM)
- Event Report BCSM (ERB)
- Connect (CONN)
- Send Charging Information (SCI)
- AC (Apply Charging)