tc gsm overview
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gsmTRANSCRIPT
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2G1330 ireless Networktures
Maguire 02.fm Total pages: [email protected]
Institutionen fr mikroelektronik ochinformationsteknik
1998, 1999, 2000,2002 G.Q.Maguire Jr. .All rights reserved. No part of this course may be reproduced, storedin a retrieval system, or transmitted, in any form or by any means,electronic, mechanical, photocopying, recording, or otherwise,without written permission of the author.
Last modified: 2002.03.14:11:59
GSM, GPRS ational Roaming, OAM. Maguire Jr.
For use in conjunction ile Network Architectures, by Yi-BingLin and Imrich Chlam s, 2001, ISBN 0-471-39492-0 Mobile and WArchitec
P4-Lecture3-20 2002.03.14
, SMS, InternLecture notes of G. Q
with Wireless and Mobtac, John Wiley & Son
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S, SMS, International Roaming, OAM:2 of 80Mobile and Wireless Network Architectures
2), International RoamingMaguire Lecture 3 GSM, [email protected] 2002.03.14
Lecture 3 GSM (Chapters 9,10, and11), GPRS (Ch. 18), SMS (Ch. 1
(Ch. 13), Operation/Administration/Maintainence (Ch. 14)
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SM)GSM, GPRS, SMS, International Roam-Mobile and Wireless Network Architectures
obileSM)
etworkperators, andMaguire Global System for Mobile Communications([email protected] 2002.03.14
Global System for MCommunications(G
designed to be a digital (wide area) wireless n driven by european telecom manufacturers, o
standardization committees very widely used around the world
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PRS, SMS, International Roaming, OAM:4 ofMobile and Wireless Network Architectures
tsg countries with internationally at different rates!)e
ration with ISDN networks
a mix-and-match systemto a lesser extent to limit
og systemsmsMaguire GSM Requirements GSM, [email protected] 2002.03.14
GSM Requiremen Service portability
mobile should be able to be used in any of the participatinroaming and standardized numbering & dialing (but possib
usable for both wireline line services and for mobile servic usable when: walking, driving, boating, (upto 250 km/h)
Quality of service and Security quality at least as good a previous analog systems capable of offering encryption
Good radio frequency utilization high spectrum efficiency co-existance with earlier systems in the same bands
Modern network following ITU recommendations - to allow efficient interope supporting voice and low rate data standardized mobility and switching support standardized interfaces between the subsystems - to allow
System optimized to limit cost of mobiles (andthe cost of the whole system) GSM required higher complexity mobiles than earlier anal subscriber cost less than or equal to existing analog syste
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S, SMS, International Roaming, OAM:5 of 80Mobile and Wireless Network Architectures
e
PSTNN
LRtabase
EIRDatabase
Gateway MSC(GMSC)
FMaguire GSM ArchitectureGSM, [email protected] 2002.03.14
GSM Architectur
Figure 1: GSM Architecture
MS Mobile Station
BSS base station system
NSS network and switching subsystem
MSCBSC
BTSMS
IWF
MESIM
Radio Link
BTS
BTS
Abis
BSS
A
PSD
HLRDatabase
AuCDatabase
VDa
NSS
TE
Um OMCX.25
X.25
BC D
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S, SMS, International Roaming, OAM:6 of 80Mobile and Wireless Network Architectures
le accessllocated bandwidth into station
period approx. 0.577 ms longx. 4.615 ms) = basic unit for the
l channel
subject to frequency hopping and
S7)Maguire Foundation GSM, [email protected] 2002.03.14
Foundation Hybrid frequency-division/time-division multip
FDMA - division by frequency of the (maximum) 25 MHz a124 carrier frequencies spaced 200 kHz apart. One or more carrier frequencies assigned to each base
Each carrier frequency divided in time, using TDMA Fundamental unit of time in this TDMA scheme is a burst Eight burst periods are grouped into a TDMA frame (appro
definition of logical channels A physical channel is one burst period per TDMA frame Slow frequency at upto 217 times per second
hopping algorithm is broadcast on the broadcast contro helps alleviate multipath fading co-channel interference is effectively randomized Note: broadcast and common control channels are not
are always transmitted on the same frequency Infrastructure based on Signalling System 7 (S
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PRS, SMS, International Roaming, OAM:7 ofMobile and Wireless Network Architectures
nsMaguire GSM contributions GSM, [email protected] 2002.03.14
GSM contributio Location-based mobility management Mobile assisted handover Temporary Mobile Subscriber ID (TMSI)
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GPRS, SMS, International Roaming, OAM:8Mobile and Wireless Network Architectures
f GSM many countries
stems (especiallyy between base stations
ll the innovations in time
error correction done by a forwardformation is repeated when it hasMaguire Distintive features of GSM GSM,[email protected] 2002.03.14
Distintive features o Cooperative development by many actors from preserved open interfaces between the subsy
between infrastructure elements -- particulariland switches)
specified a large number of interfaces! Phased release - since they could not make a
for their targeted 1991 introduction Phase 1 GSM spec. - 100 sections and 5,320 pages!
telephony - with some added features emergency calls data transmission at 2.4/4.8/9.6 kbit/s (transparent {the
error correction (FEC) mechanism}/non-transparent {innot been correctly received})
short message service (SMS) Phase 2
non-voice services and enriched telephony
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PRS, SMS, International Roaming, OAM:9 ofMobile and Wireless Network Architectures
S)Maguire Mobile Station (MS) GSM, [email protected] 2002.03.14
Mobile Station (M Subscriber Identity Module (SIM) Mobile Equipment (ME) Mobile Terminal (MT)
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ule (SIM)d can be moved from one
mber (PIN) is locked for all but
king key (PUK)twork provider(s))s, phone list, SMS messages, )
lication/ built using SIM Toolkit
required to be able to
tity (IMSI)
Maguire Subscriber Identity Module (SIM)[email protected] 2002.03.14
Subscriber Identity Mod small form factor - which can be removable an
terminal to another smart card (generally too large for handsets!) plug-in SIM (the processor and contact from a smart card)
user authenticated via a Personal Identity Nu if PIN entered incorrectly, N times, then phone
emergency calls, until you enter a PIN unbloc contains subscriber information:
some which is fixed by operator (may include preferred ne some which is changable by the user (list of short number
can be updated via: keyboard attached terminal equipment over the air (OTA) via SMS message sent by operator/app
often the SIM is owned by the operator profiles - operator/subscription info; SIMs are
hold at least two profiles contains International Mobile Subscriber Iden
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PRS, SMS, International Roaming, OAM:11Mobile and Wireless Network Architectures
(ME) keyboard, etc.
ation, handover, encoding
calls:cy band
ntity (IMEI)Maguire Mobile Equipment (ME) GSM, [email protected] 2002.03.14
Mobile Equipment the phone itself - radio and radio interface, display,
performs: radio transmission and reception, authenticand channel encoding.
note: ME with SIM can only make emergency (112) Radios operate in one or more of the following bands GSM900 since 900 MHz - the original frequen
Uplink: 890..915 MHz (= mobile station to base station) Downlink: 935..960 MHz (= base station to mobile station)
GSM1800 (also known as DCS1800) Uplink: 1710..1785 MHz Downlink: 1805..1880 MHz
GSM1900 (also known as PCS 900) Uplink: 1850..1910 MHz Downlink: 1930..1990 MHz
ME identified by International Mobile Equipment Ide
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PRS, SMS, International Roaming, OAM:12Mobile and Wireless Network Architectures
inimize interference onMS does not transmit -X)s to the paging channel, of the paging channelnserve power, both therate at the lowest powerality
from the peak power for the class
1/8 of the time - so its radiated
al strength or signal qualityhe base station controller (whichMaguire Mobile Equipment (ME) GSM, [email protected] 2002.03.14
Power saving and interference reduction To reduce the MSs power consumption and m
the air interface, during pauses in speech the this is called: Discontinuous transmission (DT Comfort noise is artificially generated by the MS
Discontinuous reception (DRX) - mobile listenbut only needs to wake up for its sub-channel
To minimize co-channel interference and to comobiles and the base transceiver stations opelevel that will maintain an acceptable signal qu Power levels can be stepped up or down in steps of 2 dBm
down to a minimum of 13 dBm (20 milliwatts for MS) only one step at a time and each step takes 60ms there are 16 power levels (i.e., 30 db of range) terminal is typically only transmitting in one time slot (i.e.,
power is on average 8db lower than the set power level) Both mobile station and BTS continually measure the sign
(based on the bit error ratio), and pass the information to tmanages power levels).
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PRS, SMS, International Roaming, OAM:13Mobile and Wireless Network Architectures
n
s
sMaguire Mobile Equipment (ME) GSM, [email protected] 2002.03.14
Classmark
32 bit quantity indicating properties of a mobile statio revision level RF power capability
(available) encryption procedures frequency capabilities (i.e., which bands) if the device is SMS capable
Figure 2: Power classes
Class GSM900 DCS1800
1 20 W 1 W vehicle mounted system
2 8 Wa
a. 1W average if using a single time slot per frame
0.25 W vehicle mounted system
3 5 W
4 2 Wb
b. 250mW average if using a single time slot per frame
portable terminals
5 0.8 W
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ID
M card the user (or at leastS).
l assembly plants.Maguire User ID Device IDGSM, [email protected] 2002.03.14
User ID Device
An important distinction in GSM is that due to the SIIMSI) can be identified separately from the device (MTMSI is assigned by the VLR to a visiting subscriber
IMEI consists of: Type Approval Code (TAC) Final Assembly Code (FAC) to identify the fina Serial number - allocated to the manufacturer
IMEI International Mobile Equipment Identity 15 digits
IMSI International Mobile Subscriber Identity 15 digits
TMSI Temporary Mobile Subscriber Identity 32 bits
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RS, SMS, International Roaming, OAM:15 ofMobile and Wireless Network Architectures
T)
ble, PCMCIA, IrDA;
Description
SMS Message Received
New MessageACKnowledgement to ME/TE
Preferred Message Storage
Service Center Address
Select Broadcast Message Type
Show Text Mode Paramaters
Set Text Mode Parameters
Restore SettingMaguire Mobile Terminal (MT)GSM, [email protected] 2002.03.14
Mobile Terminal (MGenerally a PDA, PC,
Interface can be serial (DTE-DCE) interface: serial caBluetooth,
AT commands:AT Command Description AT Command
+CNMI New message inication to TE +CMT
+CBM New Cell-Broadcast Message (CBM) +CNMA
+CMGC Send Command +CPMS
+CMGD Delete Message +CSCA
+CMGL List Message +CSCB
+CMGR Read Message +CSDH
+CMCS Send Message +CSMP
+CMGW Write Message to Memory +CRES
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
(BSS)dMaguire Base Station System (BSS)[email protected] 2002.03.14
Base Station System one or more base transceiver station (BTS) an base station controller (BSC)
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
n (BTS)ecryption
as, the interface to the PCM
ng speech channel to/fromMaguire Base transceiver station (BTS)[email protected] 2002.03.14
Base transceiver statioPerforms: channel coding/decoding and encryption/d
BTS includes: radio transmitters and receivers, antennfacility,
About 1/2 the processing is associated with transcodiGSM coding
WasyhunTypewritten Text* It provides a limited coverage area inside a network due to limited transmission power. The cell is created and users are free to roam and communicate inside the cell.size of cell determined by radio wave propagation characteristics, local morphology and expected user density
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
r (BSC)io resourcesength sent by mobile
d, shed load by: (1) rejectingnd (3) ignoring handoffsMaguire Base station controller (BSC)[email protected] 2002.03.14
Base station controlleBTSs are connected to a BSC which manages the rad call maintenance using the received signal str
stations normally every 480 ms initiate handovers to other cells, change BTS transmitter power, Task breakdown:
BSCs engineed for about 80% utilization, if overloadelocation updates, (2) rejecting MS originating calls, a
call activities ~20-25%
paging and SMS ~10-15%
mobility management ~20-25%
hardware checking/network triggered events ~15-20%
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) GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
system (NSS)orksMaguire Network and Switching Subsystem ([email protected] 2002.03.14
Network and Switching Sub MSCs
Gateway MSC (GMSC) has interconnections to other netw Databases Gateways
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s the international mobile subscriberN) and current visitor location register
for call control and servicegeographical area controlled by this
MSC
y stored in each subscribers SIM cardver the radio channel
ithin the network, where each mobileent identity (IMEI) - split into 3
certainMaguire Databases GSM, [email protected] 2002.03.14
DatabasesHome LocationRegister (HLR)
database for management of mobile subscribers, storeidentity(IMSI), mobile station ISDN number (MSISD(VLR) addresskeeps track of the services associated with each MSan HLR may be used by multiple MSCs
Visitor LocationRegister (VLR)
caches some information from the HLR as necessary provisioning for each mobile currently located in the VLR
connected to one MSC and is often integrated into the
AuthenticationCenter (AuC)
a protected database which has a copy of the secret kethis secret is used for authentication and encryption onormally located close to HLR
Equipment IdentityRegister (EIR)
contains a list of all valid mobile station equipment wstation is identified by its international mobile equipmdatabases:
White list: all known, good IMEIs Black list: bad or stolen handsets Grey list: handsets/IMEIs that are un
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ster (EIR)
ber.Maguire Equipment Identity Register (EIR)[email protected] 2002.03.14
Equipment Identity RegiOptional in a GSM network, i.e., not required
EIR block (bars) calls from a MS, not from a subscriSometimes the AuC and EIR are combined.
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GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
(OSS)
s, modifying and removingMaguire Operation Sub-System (OSS)[email protected] 2002.03.14
Operation Sub-System Operation and Maintenance Center Service management
subscription management for registering new subscriptionsubscriptions, as well as billing information
billing fraud detection
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)GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
Center (OMC)d indirectly the BTSs)etwork
overs,
cating, and correctingMaguire Operation and Maintenance Center ([email protected] 2002.03.14
Operation and Maintenance Manages the GSM functional blocks: MSC, BSC (anTask: to maintain satisfactory operation of the GSM n
Based on observing system load, blocking rates, hand
Activities: Network Management System (NMS)
modify network configuration equipment maintenance aiming at detecting,lo
faults
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RS, SMS, International Roaming, OAM:24 ofMobile and Wireless Network ArchitecturesMaguire GSM Interfaces GSM, [email protected] 2002.03.14
GSM InterfacesInterface Description
Um Radio link between MS and BTS
Abis between BTS and BSC, PCM 2 Mbit/s, G. 703
A between BSC and MSC, PCM 2 Mbit/s, G. 703
B between MSC and VLR (use MAP/TCAP protocols)C between MSC and HLR (MAP/TCAP)D between HLR and VLR (MAP/TCAP)E between two MSCs (MAP/TCAP + ISUP/TUP)F between MSC and EIR (MAP/TCAP)G between VLRs (MAP/TCAP)
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RS, SMS, International Roaming, OAM:25 ofMobile and Wireless Network Architectures
SM recommendations.
B
S
S
M
A
P
T
U
P
I
S
U
P
I
N
A
P
M
A
P TUP,ISUP,INAP,MAP
)TACP TACP
)
SCCP SCCP
MTP MTP
)64kbps(08.54)
64kbps(08.54)
C PSTNISDNMaguire GSM Interfaces GSM, [email protected] 2002.03.14
Numbers in parentheses indicate the relevant ETSI-G
Layer
3 CM(04.08)
CM(04.08)
MM(04.08)
MM(04.08)
RR(04.08)
RR BSSAP(08.06)
DTAP
RR(04.08)
BTSM(08.58)
BTSM(08.58)
BSSAP(08.06
2 LAP-Dm(04.06/08)LAP-Dm(04.06/08)
LAP-D(08.56)
LAP-D(08.56)
SCCPMTP(08.06)
SCCPMTP
(08.061 Radio
(04.04)Radio(04.04)
64kbps(08.54)
64kbps(08.54)
64kbps(08.54)
64kbps(08.54
MS BTS BSC MS
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ec. 08.54 on A bis interface and
annels
ference calls, etc.)Maguire GSM Layers GSM, [email protected] 2002.03.14
GSM Layers Layer 1: Physical layer
physical transmission channel quality measurements GSM Rec. 04.04, PCM 30 or ISDN links are used (GSM R
08.04 on A to F interfaces) Layer 2: Data link layer
Multiplexing of layer 2 connections on control/signaling ch Error detection (based on HDLC) Flow control Transmission quality assurance Routing
Layer 3: Network layer Connection management (air interface) Management of location data Subscriber identification Management of added services (SMS, call forwarding, con
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RS, SMS, International Roaming, OAM:27 ofMobile and Wireless Network Architectures
e
ol (similar to ISDNpoint signaling channelsint signaling channelstection and error correctionor control signaling
e stable connection betweenl and to maintain connection
required for mobility:Maguire GSM Air interface GSM, [email protected] 2002.03.14
GSM Air interfac Layer 1 (GSM Rec. 04.04): Um interface Layer 2 (GSM Rec. 04.05/06): LAP-Dm protoc
LAP-D): connectionless transfer of point-to-point and point-to-multi Setup and tear-down of layer 2 connections of point-to-po connection-oriented transfer with in order delivery, error de
Layer 3 (GSM Rec. 04.07/08) with sublayers fchannel functions (BCH, CCCH and DCCH): Radio resource management (RR): to establish and releas
mobile stations (MS) and an MSC for the duration of a caldespite user movements - functions of MSC: cell selection handover allocation and tear-down of point-to-point channels monitoring and forwarding of radio connections enabling encryption change transmission mode
Mobility management (MM) handles the control functions authentication assignment of TMSI,
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RS, SMS, International Roaming, OAM:28 ofMobile and Wireless Network Architectures
down calls connections:
ervices,text messages
essages, these messages areect transfer application part
ped to or from the basee with the MSC:
easurements, uplink)Maguire GSM Air interface GSM, [email protected] 2002.03.14
management of subscriber location Connection management (CM) - set up, maintain and tear
Call control (CC): Manages call connections, Supplementary service support (SS): Handles special s Short message service support (SMS): Transfers brief
Neither the BTS nor the BSC interpret CM and MM mexchanged between the MSC or the MS using the dir(DTAP) protocol on the A interface.Radio Resource Management (RR) messages are mapstation system application part (BSSAP) for exchang
Transmission mode (change) management Cipher mode management Discontinuous transmission mode management Handover execution Call re-establishment RR-session release Load management SACCH procedures
radio transmission control (power&timing, downlink), (m -general information
Frequency redefinition General information broadcasting (BCCH)
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RS, SMS, International Roaming, OAM:29 ofMobile and Wireless Network ArchitecturesMaguire GSM Air interface GSM, [email protected] 2002.03.14
cell selection information information for idle mode functions information needed for access cell identity
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dio links, metropolitan areaRG},
d 64 kbit/s formats - for
d 64 kbit/s formats - for
uires a signaling channel onRate Adapter Unit)1 framesused for user data and 2.4on)Maguire Abis interfaceGSM, [email protected] 2002.03.14
Abis interfaceDividing line between the BSC function and the BTS
BSC and BTS can be connected using leased lines, ranetworks (MANs), LANs {see UC Berkeleys ICEBETwo channel types exist between the BSC and BTS: Traffic channels (TCH): configured in 8, 16 an
transporting user data Signaling channels:configured in 16, 32, 56 an
signaling purposes between the BTS and BSCEach transceiver (transmitter + receiver) generally reqthe Abis interface, data is sent as TRAU (Transcoder(for a 16 kbit/s traffic channel (TCH), 13.6 kbit/s are kbit/s for inband signaling, timing, and synchronizati
1. It is not defined where TRAU is placed, i.e., it could be part of BTS, BSC, or MSC.
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facility channels (4 per timeslot)
and BSCotocol (inherited from ISDN)
ections identified by SAPIo the radio interface BTS and BSCell as for layer 2 managementMaguire Abis protocolsGSM, [email protected] 2002.03.14
Abis protocols Layer 1 (GSM Rec. 08.54)
2.048 Mbit/s (ITU-T: E1) or 1.544 Mbit/s (ANSI: T1) PCM with 64/32/16 kbit/s signaling channels and 16 kbit/s traffic
Layer 2 (GSM Rec. 08.56) LAP-D protocol used for data messaging between the BTS SAPI refers to the link identifier transmitted in the LAPD pr
Layer 3 (GSM Rec. 08.58/04.08) BTS management (BTSM) via three logical signaling conn
(Service Access Point Identifier): SAPI 0 is used by all messages coming from or going t SAPI 62 provides O&M message transport between the SAPI 63 is used for dynamic management of TEIs as w
functions.
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transcoder equipment, two, i.e., TRAU) is located:
ontrol and signaling
n the 2 Mbit/s or 1.544 Mbit/s PCMMaguire A Interface GSM, [email protected] 2002.03.14
A InterfaceDefines interface between the BSC and MSC
TCHs are converted from 64 kbit/s to 16 kbit/s in thecases based on where the transcoder equipment (TCE
At least 2 time slots on the PCM link are needed for cpurposes.
at BSC orBTS
traffic channel (TCH) occupies a complete 64 kbit/s timeslot ilink (layer 1, GSM Rec. 08.04)
at MSC the TCHs are 16 kbit/s on the A interface
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RS, SMS, International Roaming, OAM:33 ofMobile and Wireless Network Architectures
olsbased on the SS7 standard
PCM facility. Normally
(ITU-T: E1) or
lsrity between the BCS and MSC
) or an MSC
r request).Maguire A interface protocolsGSM, [email protected] 2002.03.14
A interface protocSignaling protocol (layer 2+3) between BSC and MSCand is transmitted along with the user data within thetimeslot 16 (TS16) of the 64 kbit/s frame is used.The following protocols are employed: Layer 1 (GSM Rec. 08.04) either 2.048 Mbit/s
1.544 Mbit/s (ANSI: T1) PCM link Layer 2 (GSM Rec. 08.06) SS7-based protoco
Message transfer part (MTP) protocol - transmission secu Signaling connection control part (SCCP) protocol SCCP connection can be initiated by a mobile station (MS An SCCP connection can involve the following protocols: From the MS:
MM: CM service request RR: Paging response MM: Location updating request MM: CM re-establishment request
From the MSC: Initiation of an external handover (BSSMAP: handove
MSC manages the SCCP connections
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rotocol - counterpart to the RRts CC and MM messages trans-Maguire A interface protocolsGSM, [email protected] 2002.03.14
Layer 3 (GSM Rec. 08.08) Base station system application part (BSSAP) protocol On MSC end:
Base station management application part (BSSMAP) pprotocol on the air interface
Direct transfer application part (DTAP) protocol transmimitted transparently through the BTS and BSC
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) are buffered then coded
D/DTX)
rm prediction (RPE-LTP)
4.75 kbit/sMaguire GSM Audio GSM, [email protected] 2002.03.14
GSM Audio Speech coding - 20ms (i.e., 160) samples (8kHz @13 bits Error protection (codec specific) Error detection (CRC) Bad Frame Handling (substitution) Voice Activity Detection / Discontinuous Transmission (VA
Manufacturer specific audio features: noise cancelling spectrum equalization echo cancellation
CODECs
Full rate (FR) 13 kbit/s , Regular pulse excitation - long teHalf rate (HR) 5.65 kbit/s VSELPEnhanced full rate (EFR) 12.2 kbit/s ACELPAdaptive Multi Rate (AMR) ACELP, 12.2, 10.2, 7.95, 7.4, 6.7, 5.9, 5.15,AMR wideband codec (under standardization)
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, SMS, International Roaming, OAM:36 of 80Mobile and Wireless Network Architectures
DigitalNewtorks
ISUP
INAPIN
POTSTUPMaguire MSC interfacesGSM, [email protected] 2002.03.14
MSC interfaces
HLR MSCC
VLRD
B
EIRF
MSCE
VLR
BG
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, SMS, International Roaming, OAM:37 of 80Mobile and Wireless Network Architectures
02)dio network (HLR, VLR, and EIR) MSC-MSC handover, security
rt)s to distributed application
ublic Land Mobile Networksc functionalities as TUP
all, time-dependent routing
rkslaced by ISUPMaguire MSC protocolsGSM, [email protected] 2002.03.14
MSC protocols MAP (Mobile Application Part) (GSM Rec. 09.
controls queries to the different databases in the mobile ra responsibilities include access and location management,
functions, O&M, SMS, and supplementary services. TCAP (Transaction Capabilities Application Pa
provides universal calls and functions for handling requestprocesses
ISUP (ISDN User Part) controls interworking (e.g. call setup/tear-down) between P
(PLMNs) and other networks, and provides the same basi INAP (Intelligent Network Application Part)
implements intelligent supplementary services (e.g. free cfunctions in a central service center)
TUP (Telephone User Part) implements interworking between PLMNs and other netwo used to provide international connections and is being rep
-
PRS, SMS, International Roaming, OAM:38Mobile and Wireless Network Architectures
nelsTwo way
orrection base-to-mobile
tion (SCH)ntrol (BCCH))t (AGCH)ess (RACH) mobile-to-base dedicatednel (SDCCH)
two-way
ated control
ted controlMaguire GSM Logical Channels GSM, [email protected] 2002.03.14
GSM Logical ChanTraffic channels Full-rate (TCH/F) @ 22.8 kbit/s
Half-rate (TCH/H) @ 11.4 kbit/s
Signalingchannels
Broadcast channelsFrequency c(FCCH)Synchroniza
Broadcast co
Common control channelsPaging (PCHAccess Gran
Random acc
Dedicated control channels
Stand-alonecontrol chan
Slow associ(SACCH)Fast associa(FACCH)
-
RS, SMS, International Roaming, OAM:39 ofMobile and Wireless Network Architectures
H)g))
e by 3 burst periodsltaneouslytersMaguire Traffic channel (TCH)GSM, [email protected] 2002.03.14
Traffic channel (TCMultiframe - group of 26 TDMA frames (120 ms lon
24 are used for traffic (voice or user data) 1 is used for the slow associated control channel (SACCH 1 is currently unused
TCHs for the uplink and downlink are separated in tim mobile station does not have to transmit and receive simu simplifies the electronic circuitry; avoids antenna duplex fil reducing complexity helps to cut power consumption
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
(BCH)ronization and frequency
ltipoint communications in to several mobiles.
C), network operator, accessgnals via the BCCH from many
g the boundaries betweene
ation of base stationrmation needed to synchronizeMaguire Broadcast channels (BCH)[email protected] 2002.03.14
Broadcast channels Carry only downlink information - mainly for synchcorrection.
However, it is the only channel capable of point-to-muwhich short messages are simultaneously transmitted Broadcast control channel (BCCH)
General information, cell-specific; e.g. local area code (LAparameters, list of neighboring cells, etc. A MS receives siBTSs within the same network and/or different networks
tells MS what their initial power level should be Frequency correction channel (FCCH)
correction of MS frequencies transmission of frequency standard to MS also used for synchronization of an acquisition by providin
timeslots and position of the first time slot of a TDMA fram Synchronization channel (SCH)
frame synchronization (TDMA frame number) and identific reception of one SCH burst provides a MS with all the info
with a given BTS
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ls (CCCH)and the BTS.
ovide access to the network.
.
the MS access to the network.
due to a call potential collisions with RACH
the paging and access grantMaguire Common control channels (CCCH)[email protected] 2002.03.14
Common control channeUplink and downlink channels between the MS card
Convey information from the network to MSs and pr Paging channel (PCH)
Downlink only MS is informed (by the BTS) of incoming calls via the PCH
Access grant channel (AGCH) Downlink only BTS allocates a TCH or SDCCH to the MS, thus allowing
Random access channel (RACH) Uplink only allows MS to request an SDCCH in response to a page or MS chooses a random time to send on this channel (note:
transmissions from other MSs)PCH and AGCH are transmitted in one channel calledchannel (PAGCH) - they are separated in time.
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ls (DCCH)H)
) is allocated
(e.g. field strengths) {informationnly), timing advance1, and upto 6 neighbors about twice
have a color code assigned toh are using the same frequency)
he TCHde is used (i.e., additional
sages associated with callecisions,
nsate for the propagation delays by advancing itsMaguire Dedicated control channels (DCCH)[email protected] 2002.03.14
Dedicated control channeResponsible for roaming, handovers, encryption, etc. Stand-alone dedicated control channel (SDCC
communications channel between MS and the BTS signaling during call setup -- before a traffic channel (TCH It takes ~480ms to transmit a message via SDDCH
Slow associated control channel (SACCH) always allocated to a TCH or SDCCH used for non-urgent procedures: radio measurement data
is used for handover decisions}, power control (downlink o 260bps channel - enough for reporting on the current cell
per second (if there is no other traffic for this channel) note that the MS is told what frequencies to monitor (BTSs
them so the that the MS can report on multiple BTSs whic Fast associated control channel (FACCH)
similar to the SDCCH, but used in parallel to operation of t if the data rate of the FACCH is insufficient, borrowing mo
bandwidth borrowed from the TCH), this happens for mesestablishment authentication of the subscriber, handover d
1. Transmission and reception of bursts at the base station must be synchronized, thus the MS must competransmission 0 .. 233 ms which is enough to handle cells of radius up to 35 km.
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network ArchitecturesMaguire Dedicated control channels (DCCH)[email protected] 2002.03.14
It takes ~40ms to transmit a message via FACCH
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, SMS, International Roaming, OAM:44 of 80Mobile and Wireless Network Architectures
f a bit (900ns) to ans)!
51 frames (235.4 ms) s)Maguire GSM Timing GSM, [email protected] 2002.03.14
GSM TimingA very elaborate timing structure ranging from 1/4 oencryption hyperframe (3 hours 28 minutes and 53.76
Unit Time
bit 3.69us
slot 156.25 bits (577 us)frame 8 slots (4.615 ms)traffic multiframe 26 frames (120 ms) or control multiframesuperframe 51 traffic multiframes or 26 control multiframes (6.12hyperframe 2048 superframes (3 hours 28 minutes and 53.76s)
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, SMS, International Roaming, OAM:45 of 80Mobile and Wireless Network Architectures
MS
PSTN1Maguire Incoming CallGSM, [email protected] 2002.03.14
Incoming Call
Figure 3: Call from fixed network to
GMSC
BSC
BTS
MS
MESIM
Radio Link
BTS
BTS
HLRDatabase
VLRDatabase
MSC
2 3
4
5
6
7
BSCBTS
BTS
8
8
8
8
8
8
8
8
8
8
8
8
9
9
111012
12
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, SMS, International Roaming, OAM:46 of 80Mobile and Wireless Network Architectures
obule is in only its rough
MSC)
LR is requested to provide a mobile sta-
bile subscriber
all necessary secuity procedures
pletedMaguire Incoming CallGSM, [email protected] 2002.03.14
Here we assume that we dont know which cell the mlocation
1 incoming call is passed from the fixed network to the gateway MSC (G2 based on the IMSI numbers of the called party, HLR is determined
3 HLR checks for the existence of the called number, then the relevant Vtion roaming number (MSRN)
4 reply transmitted back to the GMSC
5 connection is switched through to the responsible MSC
6 VLR is queried for the location range and reachability status of the mo
7 if the MS is marked reachable, then a radio call is enabled
8 radio call is executed in all radio zones assigned to the VLR
9 reply from the MS in its current radio cell
10 when mobile subscriber telephone responds to the page, then complete
11 if this is successful, the VLR indicates to the MSC that call can be com
12 call can be completed
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
t (MM)s are powered on and active
f the MS in the VLR and
cation areas (LAs), thushe MS in the last known
lled a location area identityMaguire Mobility Management (MM)[email protected] 2002.03.14
Mobility ManagemenGSM network keeps track of which mobile telephonein the network.
The network keeps track of the last known location oHLR.
Radio sites connected to the MSC are divided into lowhen a call comes for an MS, the network looks for tlocation area.
Each BTS is assigned (by the operator) a 40 bit ID - ca(LAI), with three parts: mobile country code mobile network code location area code
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, SMS, International Roaming, OAM:48 of 80Mobile and Wireless Network Architectures
end IMSI over the air (thusy a given user).cryption
se ciphering requires a user of the subscriber before it
ut it can be upto 128 bitsMaguire Security GSM, [email protected] 2002.03.14
SecurityUse of TMSI rather than IMSI - reduces the need to ssimply listening to the radio link it is harder to identif
Two major aspects of security: Authentication and En
Cipher mode management
Connection always starts in non-ciphered mode, becauspecific key and the network has to know the identitycan be used!
A3 Authentication algorithm
A5 Ciphering algorithm
A8 Ciphering key computation
Ki secret encryption key - operator determines length , b
Kc cypher key, computed based on Ki
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, SMS, International Roaming, OAM:49 of 80Mobile and Wireless Network Architectures
is turned on (user must keydware before this automatic
tgoing call. This is based onhe AuC matches the KiMaguire AuthenticationGSM, [email protected] 2002.03.14
AuthenticationUser authentication normally takes place when the MSin a PIN code on the handset in order to activate the harprocedure can start).Authentication occurs with each incoming call and ouchecking that Ki (secret encryption key) stored in tstored in SIM card of the MS.
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
cryption
A8
Ki
Kc
A5heringphering
datadata
umber Kcstem
Authentication
Home System
EncryptionMaguire Authentication and [email protected] 2002.03.14
Authentication and En
RAND
A3
Ki
A8 A3
SRESSRES =
rejectNo
Yesaccept
Kc
A5 cipheringdeciphering
datadata cip
deci
frame n
ciphered info
visited syEncryption
Authentication
MS
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RS, SMS, International Roaming, OAM:51 ofMobile and Wireless Network Architectures
5]Maguire GSM data rates GSM, [email protected] 2002.03.14
GSM data ratesThe following table of data rates is from page 39 of [
Connection Typea
a. T = Transparent, NT = Non-transparent
Two-way delay
TCH/F9.6 T 330 ms
TCH/F9.6 NT > 330 ms
TCH/F4.8 T 330 ms
TCH/F2.4 T 200 ms
TCH/H4.8 T 600 ms
TCH/H4.8 NT > 600 ms
TCH/H2.4 T 600 ms
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RS, SMS, International Roaming, OAM:52 ofMobile and Wireless Network Architectures
ng (MSC, BSC, BTS, ) to them,
ng term traffic is not cost
activitytes and cell parameterse economically continuous an easy task)Maguire System engineeringGSM, [email protected] 2002.03.14
System engineeriThe operator must choose how many of each elementorder, what capacity each must have, where to install
Since traffic does not remain constant simply installing a large enough capacity for lo
effective Therefore, system engineering is an on-goingNote: goal of cellular planning is to choose the cell si(frequency allocation, capacity, power, etc.) to providcoverage and support the required traffic density (not
-
RS, SMS, International Roaming, OAM:53 ofMobile and Wireless Network ArchitecturesMaguire System engineeringGSM, [email protected] 2002.03.14
Table of parameters, from page 101 of [5]
Area Parameters
Cell planning frequenciesbeacon frequencieshopping sequencespower control parametershandover parameterscell selection parametersBSIC
Dimensioning # of common channels# of traffic channelslocation areasperiodic location updating
Load control overload control parameters
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
zationber behavior, and (QoS)
CM frame are monitored
ent at the PCM level and
es leased from fixed network
ability can be determined (uplink)urement of the downlink BER}e) measurement in which the 260andom bit sequence (PRBS)er 1 alarmscluding:network load regarding signalingillance, bit error ratio of a BTS, frequency interference (due toindications of system overload.Maguire GSM Network [email protected] 2002.03.14
GSM Network OptimiBased on network performance & utilization, subscri
Test methods: Traffic analysis:the signaling channels in the P
and analyzed on the A bis and A interfaces Bit error ratio test (BERT): bit error measurem
the GSM-specific level (TRAU frame) PCM bit error ratio (BER) is used to verify the quality of lin
operators By evaluating the control bits in the TRAU, a bit error prob
during actual communications (in-service) {No easy meas More accurate radio link BER measurement (out-of-servic
data bits in the TRAU frame are checked using a pseudo-r Alarm monitoring - checking PCM links for lay Network quality test: lots of measurements - in
island problems, detection of coverage holes, interference,and traffic,handover failures, Receive level (RXLEV) surve(RXQUAL), multipath interference and propagation delaysnearby frequency reuse), call completion/disconnect rate,
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, SMS, International Roaming, OAM:55 of 80Mobile and Wireless Network Architectures
receive an audible beep to alert them
old},ceive a busy signal}e additional calls or to receive
er numbers under conditions defined
n certain criteria (no answer, busy, not
one no.) to the GSM network; GSMMaguire Features GSM, [email protected] 2002.03.14
FeaturesCall Waiting (CW) {network-based feature} users with a call in progress
that there is an incoming call for their MSThe incoming call can be:
accepted {the original call is put on h sent to voice mail, or rejected {in this case the caller will re
Call Hold (CH) allows the MS to park an in progress call, to makincoming calls
Call Forwarding(CF)
{network-based feature} allows calls to be sent to othby the userConditions can be either unconditional or dependent oreachable)
Calling Line ID callers network to delivers the calling line ID (telephtelephone displays the originating telephone number
-
, SMS, International Roaming, OAM:56 of 80Mobile and Wireless Network ArchitecturesMaguire GSM Phase 2+GSM, [email protected] 2002.03.14
GSM Phase 2+ High Speed Circuit Switched Data (HSCSD) General Packet Radio Service (GPRS)
-
D) GSM, GPRS, SMS, International Roam-Mobile and Wireless Network Architectures
Data (HSCSD)
l can be implemented using time for the synthesizer tohe offset of 3 slots between
changes faster, but at 3 slotse time.
ependent receivers
g, frequency hopping, and
e data connectionMaguire High Speed Circuit Switched Data ([email protected] 2002.03.14
High Speed Circuit Switched
In the basic GSM model TX/RX activities, the terminaone frequency synthesizer (even though it takes somechange from one frequency to another) - because of ttransmit and receiver.
If you only use 2 slot, you just need a synthesizer thatyou potentially need to transmit and receive at the sam
At eight time slots (i.e., continuous transmission): monitoring neighboring base stations would require an ind the terminal will be more expensive than one slot terminal power consumption will be much higher
Multi-slot systems have required changes in: cipheringenerally radio resource management functions.
Idea is simple use several time slots out of each TDMA frame for on
Reality this is taxing for the RF power systems
-
D) GSM, GPRS, SMS, International Roam-Mobile and Wireless Network Architectures
le time slot) operation
ithout data compression)re
PSTNN
VLRatabase
EIRDatabase
Gateway MSC(GMSC)Maguire High Speed Circuit Switched Data ([email protected] 2002.03.14
HSCSD depends on: Terminal Adapation Function (TAF) Interworking Functions (IWF) enhanced RLP to handle multilink (aka multip
Nokias Card Phone 2.0: HSCSD at upto 43.2 kbps (w Figure 4: GSM/HSCSD Architectu
MSCBSC
BTSMS
IWF
MESIM
Radio Link Protocol (RLP)
BTS
Abis
BSS
A
PSD
HLRDatabase
AuCDatabase
D
TE
Um OMCX.25
X.25
BC D
TAF
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ice (GPRS)d air interface resources
over GPRS, (and X.25Maguire General Packet Radio Service (GPRS)[email protected] 2002.03.14
General Packet Radio ServGPRS features: True packet radio system - sharing network an Volume based charging TCP/IP (Internet & Intranet) interworking, SMS
interworking) Peak data rate from 9.05 kbps .. 171.2 kbps Protocols designed for evolution of radio
EDGE - new GSM modulation Migration into 3rd Generation
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, SMS, International Roaming, OAM:60 of 80Mobile and Wireless Network Architectures
iphering & compression, mobility,MSC/VLR, charging & statistics,
y it is a network router)ding them to right SGSN,ination, filtering end userstical information of data
obile IP to GSM systems.Maguire GPRS nodesGSM, [email protected] 2002.03.14
GPRS nodesGPRS introduces new network elements Serving GPRS Support Node (SGSN)
authentication & authorization, GTP tunneling to GGSN, cmanagement, session management, interaction with HLRas well as NMS interfaces.
Gateway GPRS Support Node (GGSN) interfacing to external data networks (basicall
encapsulating data packets in GTP and forwarrouting mobile originated packets to right desttraffic, as well as collecting charging and statinetwork usage
GPRS is the result of committees trying to adapt M
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, SMS, International Roaming, OAM:61 of 80Mobile and Wireless Network Architectures
also interwork to PSDNs.
e
VLRatabase
EIRDatabase
Gateway MSC(GMSC)
GGSN
Internet
Gn Gi
GrGc
CGF Billingsystem
Ga
fMaguire GPRS nodesGSM, [email protected] 2002.03.14
The figure is over simplified - since the GGSN could
Figure 5: GSM/GPRS Architectur
MSCBSC
BTS
MS
MESIM
Radio Link (with radio media access protocol)
BTS
BSS
PLMN
HLRDatabase
DTE
SGSN
BSCBTS
BSC
BTS
BTS
BTSGPRS
Backbone
GsGb
GnGa
GAuC
Database
GGSN Gp
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RS, SMS, International Roaming, OAM:62 ofMobile and Wireless Network Architectures
se.g. a SGSN or a
d a SGSN
of GPRS networkMaguire GPRS Interfaces GSM, [email protected] 2002.03.14
GPRS InterfaceGa Charging data collection interface between a CDR transmitting unit (
GGSN)Gb between a SGSN and a BSS
Gc between a GGSN and a HLR
Gd between a SMS-GMSC and a SGSN, and between a SMS-IWMSC an
Gf between an SGSN and a EIR
Gi reference point between GPRS and an external packet data network
Gn between two GSNs within the same PLMN
Gp between two GSNs in different PLMNs (Gp interface allows support services across areas served by the co-operating GPRS PLMNs.)
Gr between an SGSN and a HLR
Gs between a SGSN and a MSC/VLR
-
PRS, SMS, International Roaming, OAM:63Mobile and Wireless Network Architectures
mestems)
142.5 dB and the maximum
CS4
kbps 21.4 kbps
None
B 128.5 dB
290 m
bits 625 bits
8 bits 19345 bitsMaguire GPRS Coding SchemesGSM, [email protected] 2002.03.14
GPRS Coding ScheFour schemes (but only CS1 and CS2 are in early sys
For comparison for GSM the worst-case link budget iscell range is 730 m.
Coding Scheme CS1 CS2 CS3
User Data Rate 9.05 kbps 13.4 kbps 15.6
CorrectionCapability
Highest
Worst-link Buget 135 dB 133dB 131 d
Maximum CellRange
450 m 390 m 350 m
40 bytes (320 bits)of payloadsee [9], pg. 33
1956 bits 1132 bits 1018
1500 bytes (12000bits)
55787 bits 32490 bits 2721
-
PRS, SMS, International Roaming, OAM:64Mobile and Wireless Network Architectures
o spread the effect of burstMaguire GPRS Coding SchemesGSM, [email protected] 2002.03.14
But the real problem is that GPRS uses interleaving terrors - but this means that the delay is always high!
-
SSD) GSM, GPRS, SMS, InternationalMobile and Wireless Network Architectures
Service Data
to the network as USSD.
ys.d to servers (which actually
ay transactions.Maguire Unstructured Supplementary Service Data ([email protected] 2002.03.14
Unstructured Supplementary(USSD)
When MS can not recognize text - it simply passes it
USSD supports all digits, asterisk (*), and punt (#) keA USSD server is connected to the HLR via MAP anprovide a specific service) via TCP/IP.USSD is thought to be ~7x faster than SMS for two-w
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
e (SMS)message) delivery (similar
held for later delivery. ToS, the network expects toessage was correctly
rs of GSM default Alphabet
of content
ered by any GSM network
point service
Maguire Short Message Service (SMS)[email protected] 2002.03.14
Short Message ServicShort Message Service (SMS) offers connectionless (to two-way-paging)If the GSM telephone is not turned on, the message isEnsure that each time a message is delivered to an Mreceive an acknowledgement from the MS that the mreceived.
SMS supports messages up to 140 octets (160 characte- see GSM 03.38) in length.SMS concatination - combines several messages
SMS compression - defined standard for compression
With internation roaming these messages can be delivaround the world to where ever the MS currently is.
Two types of messages: cell broadcast and point-to-
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
rchitecture
N
GSMnetwork
OriginatingMS
WMSCMaguire Short Message Service [email protected] 2002.03.14
Short Message Service ASM-SC Short Message Service Centre
SMS GMSC SMS Gateway MSC
IWMSC Interworking MSC
Figure 6: SMS Architecture
SMS GMSCBSC
BTS
MS
IWF
MESIM
BTS
BSS
PSD
TE
ISM-SC
SM-SC
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, SMS, International Roaming, OAM:68 of 80Mobile and Wireless Network Architectures
protocolsS capacity in bulk, they
ators that they haveMaguire SM-SCs GSM, [email protected] 2002.03.14
SM-SCs High reliability High availability High performance existing SM-SCs talk TCP/IP as well as other There exist SMS brokers from whom you can buy SMreceive your messages and then transfer them to operagreements with.
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RS, SMS, International Roaming, OAM:69 ofMobile and Wireless Network Architectures
Ss
ss card, modify the default icon, Maguire Three kinds of SMSsGSM, [email protected] 2002.03.14
Three kinds of SMUser-specific display to a user
ME-specific ME processes the message when it is receivedNokia has special function to play ring tone, display a busine
SIM-specific SIM processes the message when it is received(for use via SIM toolkit applications)
-
PRS, SMS, International Roaming, OAM:70Mobile and Wireless Network Architectures
agesxt)d)n keyboard)eir frequency and of [11])out probably string (see page 45
s 47-48 of [36])48-49 of [36]) and, and Korean (see page 49 of [36])Maguire Entering Short MessagesGSM, [email protected] 2002.03.14
Entering Short MessTo improve the speed of entering SMSs (and other te Full keyboards (such as Ericssons Chat Boar Onscreen keyboard (such as Plams on-scree Fitaly keyboard - arranges letters based on th
probability transitions in English (see page 43 Predictive text input algorithms
Tegic T9 - utilizes numeric keypad and probability to work of [11])
e-acutes Octave keyboard (see pages 46-47 of [36]) Handwriting recogntion
Word recognition, such as Psions CalliGrapher (see page Character recognition, such as Palms Graffiti (see pages CJKOS - an OS extension for Palm for Chinese, Japanese
Speech recognition
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
m (VMS) (i.e., forwards them) to aeft unattended (after ringing
) to the MS to let the user
ty - to over-write last VMAtatus voice messages (forg).Maguire Voice Messaging System (VMS)[email protected] 2002.03.14
Voice Messaging SysteA value-added service which redirects incoming callsvoice mailbox when MS is turned off, low on battery, lfor xx seconds) or temporarily out of coverage.A Voice Message Alert (VMA) can be send (via SMSknow there is a waiting voice message.
Note that you can use SMSs replace message facili- thus there will only be one message with the latest sexample saying: You have N voice messages waitin
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
ail (VPIM)rrently a Proposed Standardn of Internet Mail originallyessaging systems
tml
xtensions, voice directorytial non-deliveryMaguire Voice Profile for Internet Mail (VPIM)[email protected] 2002.03.14
Voice Profile for Internet MVoice Profile for Internet Mail (VPIM) Version 2 is cu(RFC 2421) Applicability Statement, it is an applicatiointended for sending voice messages between voice mhttp://www.ema.org/vpimhttp://www.ietf.org/html.charters/vpim-charter.h
VPIM v3 Specification add extensions: IMAP voice eprofiles, content negotiation details for voice and parnotifications.
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PRS, SMS, International Roaming, OAM:73Mobile and Wireless Network Architectures
ingeive calls in any GSM
orldwide.
l operators.
etwork (for example, in(MSISDN) still looks like itpid aspects of GSM.}s the person you are calling,
tromboning. For four
same phone number everywhere!
n you think!Maguire International Roaming GSM, [email protected] 2002.03.14
International RoamGSMs roaming feature allows a user to make and recnetwork and to use the same user-specific services w
Requires a roaming agreement between the individua
The basic problem is that when you roam to another nanother country) - your Mobile Station ISDN numberis in your home network. {This is one of the more stuWorst is if you are in the same (non-home) network aas this results in two international calls! This is due tosolutions see section 13.2 of [12], pages 242-249.
Good news With worldwide roaming the MS is accessible via the
Bad news It could be very expensive - much more expensive tha
-
GSM, GPRS, SMS, International Roaming,Mobile and Wireless Network Architectures
aintainencellows ITU-T;sodel, which has several
lk the talk to walk the walk!
to provide overall of mobile equipment, HLR
Elements (NEs): HLR,
Communication Function
equipmentkstation functions (WSFs)Maguire Operation/Administration/[email protected] 2002.03.14
Operation/Administration/MOperation/Administration/Maintainence (OA&M) foTelecommuncations Management Network (TMN) mcomponents:
I personally find this ITU-T speak! But you have to ta
Operations system (OS) OS uses Operating System Function (OSF) management, billing, account, managementmeasurement,
Network Element Functions(NEFs)
provides monitoring and control of NetworkVLR, AuC, EIR, MSC, BSC, and BTS
Data CommunicationNetwork
OS, NEs, and other TMN elements via Data(DCF)
Mediation device (MD) adapts the OS to a specfic NEQ-Adapter (QA) uses Q-adapter function to adapte non-TMNWorkstation (WS) OA&M personnel interact with OS via Wor
-
DGE) GSM, GPRS, SMS, InternationalMobile and Wireless Network Architectures
SM Evolution
crease network capacity
pete with 3G networksde area)Maguire Enhanced Data Rates for GSM Evolution ([email protected] 2002.03.14
Enhanced Data Rates for G(EDGE)
enhanced modulation technique designed to inand data rates in GSM networks
provide data rates up to 384 Kbps. EDGE lets operators without a 3G license com
(since the data rates are comparable in the wi
-
N) GSM, GPRS, SMS, International Roam-Mobile and Wireless Network Architectures
work (GERAN)SM Evolution (EDGE)Maguire GSM/EDGE Radio Access network ([email protected] 2002.03.14
GSM/EDGE Radio Access netthe radio interface used in Enhanced Data Rates for G
Maximum data rate: 384 kbps
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, SMS, International Roaming, OAM:77 of 80Mobile and Wireless Network Architectures
including 4 new Data a incremental redundancy traffic channels.ith different QoS profiles.
re small delay is required taking place, needs somewhat
rrors (may require multipleMaguire EGRPS GSM, [email protected] 2002.03.14
EGRPSEGPRS = EDGEan extension/enhancement of GPRSPacket Traffic Channels using 8-PSK modulation andmechanism extended to the GMSK based data packet
Support for simultaneous, multiple radio access bearers w New bearer classes:
Conversational Class - Voice & video conferencing whe Streaming Class - Capable of processing as transfer is
constant delay and throughput Interactive Class - on-line applications Background Class - Delay insensitive but requires few e
re-transmissions to hide errors)
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RS, SMS, International Roaming, OAM:78 ofMobile and Wireless Network Architectures
obile Communications,
he GSM systems, IEEE, 1995.ations Systems, Chapter 7,dison-Wesley, 1997,
on Vol. 2, Acterna Eningen
_notes/gsm_SW-EN-PG02-11
ital Mobile Communicationpere, FinlandMaguire Further reading GSM, [email protected] 2002.03.14
Further readingGSM
[1] M. Mouly and MB Paulet, The GSM System for MMouly and Paulet, 1992
[2] M. Mouly and MB Paulet, Current evolution of tPersonal Communications, vol. 2, no. 5, pp. 9-19
[3] David J. Goodman, Wireless Personal CommunicGSM: Pan-European Digital Cellular System, AdISBN 0-201-63470-8
[4] Marc Kahabka, GSM Pocket Guide revised versiGmbH, 72795 Eningen u. A., Germanyhttp://www.acterna.com/downloads/application00-AE.pdf-
[5] Petri Jarske, The GSM System, Principles of DigSystems, 2001 edition, Technical University Tam
-
RS, SMS, International Roaming, OAM:79 ofMobile and Wireless Network Architectures
01.PDF
lity Profiles for Locationertation, NorwegianTelematics, 12 Jan. 1998.
tml
ata Services, Dr. Tech.Department of Information
ccess Networks, Dr. Tech.Department of Information
ving the performance of, Cingular Wireless LLC,Maguire Further reading GSM, [email protected] 2002.03.14
http://www.cs.tut.fi/kurssit/83150/DigiCom20
[6] Sudeep Kumar Palat, Replication of User MobiManagement in Mobile Networks, Dr. Ing. dissUniversity of Science and Technology, Dept. of
[7] GSM securityhttp://www.isaac.cs.berkeley.edu/isaac/gsm.h
GPRS
[8] Jari Hmlinen, Design of GSM High Speed Ddissertation ,Tampere University of Technology,Technology, 4 October 1996.
[9] Jouni Mikkonen, Quality of Services in Radio Adissertation,Tampere University of Technology, Technology, 19 May 1999.
[10]Don Zelmer, GPRS, EDGE, & GERAN: ImproGSM & TDMA Wireless by Packet Capabilities
-
RS, SMS, International Roaming, OAM:80 ofMobile and Wireless Network Architectures
day, June 6, 20011/Presentationfolder/T1P
r, Klaus Rintdoff, andgy and Architecture of002, ISBN 0-201-72215-1
Mobile Network2001, ISBN 0-471-39492-0
Mobile Network001, ISBN 0-471-39492-0Maguire Further reading GSM, [email protected] 2002.03.14
SUPERCOMM 2001, Atlanta, Georgia, Wedneshttp://www.atis.org/atis/Pictures/Supercomm01zelmer3Gtemplate2.PDF
SMS
[11]Jochen Burkhardt, Dr. Horst Henn, Stefan HeppeThomas Schck, Pervasive Computing: TechnoloMobile Internet Applications, Addison-Wesley, 2
International Roaming
[12]Yi-Bing Lin and Imrich Chlamtac, Wireless and Architectures, , Chapter 13, John Wiley & Sons,
Operation/Administration/Maintainence
[13]Yi-Bing Lin and Imrich Chlamtac, Wireless and Architectures, Chapter 14, John Wiley & Sons, 2
GSM, GPRS, SMS, International Roaming, OAMLecture notes of G. Q. Maguire Jr.Lecture 3Global System for Mobile Communications(GSM)GSM RequirementsGSM ArchitectureFoundationGSM contributionsDistintive features of GSMMobile Station (MS)Mobile Equipment (ME)Power saving and interference reductionClassmark
User ID Device IDMobile Terminal (MT)Base Station System (BSS)Base transceiver station (BTS)Base station controller (BSC)Network and Switching Subsystem (NSS)DatabasesEquipment Identity Register (EIR)Operation Sub-System (OSS)Operation and Maintenance Center (OMC)GSM InterfacesGSM LayersGSM Air interfaceAbis interfaceAbis protocolsA InterfaceA interface protocolsGSM AudioCODECs
MSC interfacesMSC protocolsGSM Logical ChannelsTraffic channel (TCH)Broadcast channels (BCH)Common control channels (CCCH)Dedicated control channels (DCCH)GSM TimingIncoming CallMobility Management (MM)SecurityCipher mode management
AuthenticationAuthentication and EncryptionGSM data ratesSystem engineeringGSM Network OptimizationFeaturesGSM Phase 2+High Speed Circuit Switched Data (HSCSD)General Packet Radio Service (GPRS)GPRS nodesGPRS InterfacesGPRS Coding SchemesUnstructured Supplementary Service Data (USSD)Short Message Service (SMS)Short Message Service ArchitectureSM-SCsThree kinds of SMSsEntering Short MessagesVoice Messaging System (VMS)Voice Profile for Internet Mail (VPIM)International RoamingOperation/Administration/MaintainenceEnhanced Data Rates for GSM Evolution (EDGE)GSM/EDGE Radio Access network (GERAN)EGRPSFurther readingGSMGPRSSMSInternational RoamingOperation/Administration/Maintainence