Channel request (RACH)MS NETWORK

Immediate assignmentImmediate assignment (AGCH)

Service request (SDCCH)

Service request

Authentication request (SDCCH)

Authentication response (SDCCH) Authentication

Ciphering mode command (SDCCH)

Ciphering mode complete (SDCCH) Ciphering mode setting

Setup (SDCCH)

Call initiationCall proceeding (SDCCH)

Assignment command (SDCCH)

Assignment complete (FACCH) Assignment of traffic channel

Alert (FACCH)

Call confirmation

Connect (FACCH)

Connect acknowledged (FACCH) Call accepted

Signalling (Mobile Originating Call)

Page request (PCH)MS NETWORK

Immediate assignmentChannel request (RACH)

Page response (SDCCH)

Service request

Authentication request (SDCCH)

Authentication response (SDCCH) Authentication

Ciphering mode command (SDCCH)

Ciphering mode complete (SDCCH) Ciphering mode setting

Setup (SDCCH)

Call initiationCall confirmation (SDCCH)

Assignment command (SDCCH)

Assignment complete (FACCH) Assignment of traffic channel

Alert (FACCH)

Call confirmation

Connect (FACCH)

Connect acknowledged (FACCH) Call accepted

Immediate assignment (AGCH)

Signalling (Mobile Terminating Call)

Call Phases (MOC case)MS BTS BSC

AUTHENTICATION (SDCCH)Phase 2 : MM signalling

CIPHERING MODE (SDCCH)Phase 8 : Ciphering

TMSI REALLOCATION (SDCCH)

SETUP (SDCCH)

Phase 2 : MM signalling

CH. REQUEST (RACH)

IMMEDIATE ASSIGN(AGCH)

SERVICE REQUEST (SDCCH)

Phase 1 : Paging, initial MS

CH.RELEASEPhase 4 : Release

ALERTING & CONNECT (FACCH)

Phase 2 : MM signalling

CONN. ACK. and MEASUREMENTPhase 15 : Conversation

DISCONNECT & RELEASE (FACCH)

Phase 4 : Release

ASSIGNMENT (SDCCH-FACCH)Phase 3 : Basic assignment

• Signalling procedures are used during the 15 phases in a basic call

• Certain parameters influence the setting up and the release of a call