GSM TOWARDS LTE NETWORKS

Lecture # 3

SUBSCRIBER IDENIFIERS

SIM MSISDN IMEI IMSI

GSM IDENIFIERS IMEI – International Mobile Equipment Identity

IMEI is an internationally-unique serial number allocated to the MS hardware at the time of manufacture. It is registered by the network operator and (optionally) stored in the AuC

for validation purpose.

MSISDN – Mobile Subscriber ISDN Number

MSISDN represents the true or dialed number associated with the subscriber.It is assigned to the subscriber by the network operator and is stored in the SIM. It is possible for the MS to hold more then one MSISDN.

GSM IDENIFIERSIMSI– International Mobile Subscriber Identifier

When a subscriber registers with a network operator, a unique subscriber IMSI identifier is issued and stored in the SIM of the MS. A mobile station can only function fully if it is operated with a valid SIM inserted into a MS with a valid IMEI.

MSRN – Mobile Station Roaming Number

The MSRN is a temporary, location-dependent ISDN number issued by parent VLR to all MSs within its area of responsibility. It is stored in the VLR and associated HLR but in MS. The MSRN is used by the VLR Associated MSC for all call routing within the MSC/VLR service area.

List of Abbreviations

ACK: Acknowledge. ACM: Answer Complete Message. ANM: Answer Message. APN: Access Point Name. AUC:Authentication Center. BSC: Base Station Controller. BSSMAP: Base Station System Management

Application Part. BTS: Base Transceiver Station. CS1+: Channel signaling. FI: First Interrogation. FIR: First Interrogation Response.

List of Abbreviations

GGSN: Gateway GPRS Support Node. GPRS: General Packet Radio System. HLR: Home Location Register. HO: Handover. HPLMN: Home Public Line Mobile Network. IAM: Initial Address Message IDP: Initial Detect Point. IMSI: International Mobile Subscriber Identification. IN: Intelligent Network. IP: Internet Protocol. ISUP: ISDN User Part.

List of Abbreviations ITSC: International Telephone Switching Center. LAN:Local Area Network. MAP: Mobile Application Part. MGT:Mobile Global Title. MS: Mobile System. MSC: Mobile Switching Center. MSISDN: Mobile Station ISDN Number. MSRN: Mobile Station Roaming Number. PDP: Packet Data protocol. PRN: Provide Roaming Number. SCP: Service Control Point. SGSN: Serving GPRS Support Node.

List of Abbreviations

SPC: Signaling Point Code. SRI: Send Routing Information. SSF: Switching Service Function. SSN: Sub-System Number.

Location Update

Location update request

Location Update Accepted

MSISDN VLR

IMSI = 424-02-624

STP

HLR/AUC

MSC

BSC BTSSSN=7

SSN=6

SSN=254

Call from MS to MS in HPLMN

1. Channel Request

4. SRI

5. PRN

6. PRN

7. SRI

2. AUT REQ & RES

(MSISDN)

(IMSI)

(MSRN)

(MSRN)

8. Paging Global Message

9. Paging Response

10. Setup

11. Alert

3. Setup

12. connect

MAP

BSSMAP

MSISDNIMSI

IMSIMSRN

11. Alert

12. connect

HLRHLR Add.HLR SPCHLR SSN

MSC VLRVLR Add.VLR SPCVLR SSN

BSC

BTS BTS BTSBTS

BSC

SSN=7

SSN=6

SSN=254SSN=254

Call from PSTN to MS in HPLMN

(MSISDN)

(MSISDN)

(IMSI)

(MSRN)

(MSRN)

(MSRN)

7. Paging Global Message

8. Paging Response

9. Setup

10. Alert

12. connect

ISUP

MAP

BSSMAP

MSISDNIMSI

IMSIMSRN

MSC

HLRHLR Add.HLR SPCHLR SSNGMSC

BTSBTS BTS

BSC

VLRVLR Add.VLR SPCVLR SSNSSN=7

SSN=8

SSN=6

SSN=254

Prepaid Call from MS to MS in HPLMN

1. Channel Request

8. SRI

9. PRN

10. PRN

11. SRI

2. AUT REQ & RES

(MSISDN)

(IMSI)

(MSRN)

(MSRN)

12. Paging Global Message

13. Paging Response

14. Setup

15. Alert

3. Setup

16. connect

MAP

BSSMAP

MSISDNIMSI

IMSIMSRN

15. Alert

16. connect

4. IDP

5. FI

6. FIR

7. Connect

CS1+

SCP

MSC

HLRHLR Add.HLR SPCHLR SSN

VLRVLR Add.VLR SPCVLR SSN

BTS BTS BTS

BSCBSC

BTS

SSN=7

SSN=6

SSN=254SSN=254

Handover

1. HO REQ

2. Activation order

4. HO Access Burst

3. New TCH info.

5. Timing Advance

6. HO detected

7. HO complete

Inter MSC Handover

MSC

Old MSC

MSC

New MSC

BSCOld BSC

New BSCBSC

Old BTS

New BTS

SSN=254

SSN=254

SSN=7

SSN=7

SMS Mobile Originating & SMS Mobile Terminating

2. Send SM and

Ack.

1. Service Req.

3. Check SMS sub. & send

SM

4. Send SM

5. Report

6. Ack

7. Routing Info REQ and

RES

8. Forward SM

MSC

STP B-Number

9- Delivered

IMSI/MSC Address scHLRExisting SIMA

Proposal: empower

BSCBTS SSN=7

SSN=254

SSN=6

GPRS

SGSN GGSN

1. Send PDP

2. AUC Check and RES

3. SGSN validates the request

4. Send APN to GGSN

5. GGSN asks for IP6. Send IP

7. Send IP

HLR

BSCBTSSSN=254

SSN=6

WIRELESS ACCESS EVOLUTION

New ServicesNew Services EfficiencyEfficiency More Data More Data

Services Services requiredrequired

Broadband

Subscribers

Voice

CoverageCoverage MobilityMobility

Voice QualityVoice Quality PortabilityPortability CapacityCapacity Data ServiceData Service

BroadbandBroadband Network Network

SimplificationSimplification Cost of Cost of

OwnershipOwnership