CAMEL Network Architecture

HLR: Home Location Register
VLR: Visited Location Register
MSC: Mobile Switching Center
GMSC: Gateway Mobile Switching Center
SSF: Service Switching Function
SRF: Specialized Resource Function

Information Flows used by CAMEL

CAP Information flows between network entities in circuit switched call control.

SSF to SCF

·         Activity Test

·         Apply Charging Report

·         Call Information Report

·         Disconnect

·         Release

·         Event Report BCSM

·         Initial Call Attempt Ack

·         Initial DP

·         Move Leg Ack

·         Split Leg Ack

SCF to SSF

·         Activity Test

·         Apply Charging

·         Call Gap

·         Call Information Request

·         Cancel

·         Collect Information

·         Connect

·         Connect To Resource

·         Continue

·         Continue with Argument

·         Disconnect Forward Connection

·         Disconnect Forward Connection with Argument

·         Disconnect Leg

·         Establish Temporary Connection

·         Furnish Charging Information

·         Initiate Call Attempt

·         Move Leg

·         Play Tone

·         Release Call

·         Request Report BCSM Event

·         Reset Timer

·         Send Charging Information

·         Split Leg

SCF to SRF

·         Activity Test

·         Cancel

·         Play Announcement

·         Prompt And Collect User Information

SRF to SCF

·         Activity Test

·         Assist Request Instructions

·         Prompt And Collect User Information Ack

Specialized Resource Report