IMS MO SIP Signaling Flow with QoS IP Multimedia Subsystem Series

P-CSCF Discovery Procedures (A)

UE SGSN GGSN

(1) Active PDP Context Request

(2) Create PDP Context Request

(4) Create PDP Context

Response (+ P Address)

(5) Activate PDP Context

Accept (+ P Address)

(3) Obtain P-CSCF Address from configuration database

P-CSCF Discovery Procedures (B)

(1) PDP Context Activation

Procedure （ as in A)

UE

SGSN

DHCP

DNS

GGSN

(1) PDP Context Activation Procedure(as in A)

(2) DHCP Query & Resp

(3) DNS Query & RespDefault PDP

Context

Mobile Originating

P-CSCF (PDF)

(3) Invite

(4) 100 Trying

UE

SGSN

GGSN

(1) Invite

(2) 100 Trying

S-CSCF

(6) Invite

(7) 100 Trying

AS

(5) Trigger AS based on IFC

P-CSCF (PDF)

(9) 183 Session Progress

UE

SGSN

GGSN

(11) 183 Session Progress (+ Media

Authorization Token)

S-CSCF

(8) 183 Session Progress

Mobile Originating (Cont’d)

(10) Authorize QoS Resources

Mobile Originating (Cont’d)

P-CSCF (PDF)

(14) PRACK

(17) 200 (OK)

UE

SGSN

GGSN

(12) PRACK

(18) 200 (OK)

S-CSCF

(15) PRACK

(16) 200 (OK)

(13) Resource Reservation

Mobile Originating (Cont’d)

P-CSCF (PDF)UE

SGSN

GGSN S-CSCF

(a) Activate PDP Context

(b) Create PDP Context

(c) COPS: REQ

(d) COPS: DEC

(e) COPS: RPT

(f) Response

(g) Accept

Mobile Originating (Cont’d)

P-CSCF (PDF)

(20) Update

(23) 200 (OK)

UE

SGSN

GGSN

(19) Update

(24) 200 (OK)

S-CSCF

(21) Update

(22) 200 (OK)

P-CSCF (PDF)

(26) 180 Ringing

UE

SGSN

GGSN

(27) 180 Ringing

S-CSCF

(25) 180 Ringing

Mobile Originating (Cont’d)

Mobile Originating (Cont’d)

P-CSCF (PDF)

(29) PRACK

(32) 200 (OK)

UE

SGSN

GGSN

(28) PRACK

(33) 200 (OK)

S-CSCF

(30) PRACK

(31) 200 (OK)

Mobile Originating (Cont’d)

P-CSCF (PDF)

(39) ACKUE

SGSN

GGSN

(36) QoS Authorizati

on

S-CSCF

(34) 200 (OK)

(Invite)

(40) ACK

(35) 200 (OK)

(Invite)

(37) 200 (OK) (Invite)

(38) ACK(a) COPS:

DEC

(b) COPS: RPT

Mobile Originating (Cont’d)

P-CSCF (PDF)

UE

SGSN

S-CSCF

Media Stream

GGSN

Mobile Originating (Cont’d)

P-CSCF (PDF)

(5) Bye

(8) 200 (OK)

UE

SGSN

GGSN

(1) Bye

(9) 200 (OK)

S-CSCF

(6) Bye

(7) 200 (OK)

(2) Release PDP

(3) Rls Resp(4) Remove

Res Rsrv

thank

you