CAMEL (Customized Application for the
Standard Releases
The ETSI GSM Releases
European standardisation activities
– CAMEL Phase 1 standardised by ETSI in 1996, as part of the GSM R96
– CAMEL Phase 2 standardised by ETSI in 1997, as part of the GSM R97
– In 1998, enhancements to CAMEL Phase 2 released by ETSI, as part of GSM R98
The 3GPP 3G Core Network Releases…
Global standardisation activities
– CAMEL Phase 3 specified by 3GPP in 1999, as part of the 3G Core Network R99.
– 3GPP Rel-4 does not contain new functionality for CAMEL.
– 3GPP Rel-5 contains CAMEL Phase 4.
CAMEL Application Part (CAP)
CAP is a derivative of ETSI CS1
– ITU-T CS; Q.1210 series (Core INAP CS1)
– ETSI EN 300 374 series (ETSI CS1)
– ETSI EN TS 101 046 - GSM TS 09.78 (CAMEL Application Part, CAP V1, V2)
– 3GPP TS 29.078 (CAMEL Application Part, CAP V3, V4)
Camel Phase 1
– Number Translation, Call redirection
Camel Phase 2
– Charging Control, User Interaction
Camel Phase 3
– GPRS Control, SMS-MO, Mobility Trigger, SS interaction, Dialed service
Camel Phase 4
– Mid-Call trigger, Call-party handling, SCP initiate, SMS-MT
CAMEL Phase 1 Architecture
Basic control of
- No announcements
- No prepaid charging
AnyTimeInterrogation
- Call handling is specified in GSM TS 03.18 ("Basic Call Handling"). Interaction between the BCSM and the gsmSSF is specified in GSM TS 03.78 ("CAMEL stage 2").
- BCSMs have Detection Points (DPs) and Call States. The SCP may be contacted at DPs for Service Logic invocation or for instructions.
- For every MO Call or MF Call, O-BCSM invoked in MSC or GMSC.
- For every MT Call, T-BCSM invoked in GMSC.
- CAMEL Phase 1, Phase 2, Phase 3 and Phase 4 have different BCSMs (more TDPs/EDPs).
- Three types of DPs exist:
Trigger Detection Point (TDP)
- TDP may be statically armed (in O-CSI or T-CSI).
- CAMEL Service may be invoked from a TDP, provided that trigger conditions, if available, are fulfilled.
Event Detection Point – Notify (EDP-N):
- EDP-N may be dynamically armed within a Service Logic.
- When an EDP-N is met, the SCP is notified. Call processing continues.
Event Detection Point – Interrupt (EDP-R):
- EDP-R may be dynamically armed within a Service Logic.
- When an EDP-R is met, the SCP is notified. Call processing is suspended. The SSF waits for instructions from the SCP.