GSM AND
`
`PERSONAL
`
`COMMUNICATIONS
`
`HANDBOOK
`
`P |e.
`
`
`COMMUNICATIONSSERIES
`
`MALCOLM W. OLIPHANT Ae Artech House Publishers :osrow-
`
`
`
`MOBILE
`
`
`
`SIEGMUND M. REDL
`
`MATTHIAS K. WEBER
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`
`
`
`
`Short message
`service
`
`fe GSM short message service (SMS) pro-
`vides a unique means of bringing short
`alphanumeric (letters and numbers) mes-
`sagesor other kindsof information to the user
`of a mobile telephone. The messages appear
`on the phone’s display, whichis usually an
`LCD. GSM distinguishes two different types
`of short messaging:
`
`1. A dedicated service, between two parties,
`which requires the establishment of a
`(dedicated) point-to-point bearer link,
`thus the name point-to-point SMS;
`2. Broadcast service between the network
`(through one or more base stations) and
`all users withina cell or service area. This
`is called point-to-omnipointor cell broadcast
`SMS.
`
`Contents
`
`61 Short message
`Service: point-to-point
`S52
`SMS cell
`Broadcast
`
`;$
`
`¢
`
`
`
`
`
`FORD EX. 1018
`
`et|
`
`FORD EX. 1018
`
`

`

`212
`
`GSM and Personal Communications Handbook
`
`6.1 Short message
`service: point-to-point
`
`The point-to-point service may be comparedto the familiar paging serv-
`ice, but it
`is much more comprehensive. Traditional paging services
`deliver messages through an operator or computer, whereas GSM addi-
`tionally allowsdirect (bidirectional) messaging without operatorinterac-
`tion. Sophisticated two-way paging (Motorola’s FLEX family of protocols
`isan example) has recently appeared in the paging and messaging indus-
`try that closely mimics GSM’s SMS,thus assuring us the tiny pagers we
`knowso well are notlikely to disappear, even though they do not have
`GSMs voice services. Nevertheless, GSM’s SMSallows anyone to send
`alphanumeric messages to a mobile userat any time. Short messages
`might besent because the recipient did not respond to a call, or has not
`switched on his mobile phone,or is busy on another phone,or cannot be
`reached for someotherprivate reason. The “store-and-forward” mecha-
`nism behind SMS makessure that whentherecipient's phone cannot be
`immediately reached, the message is eventually delivered when the
`receiving subscriber’s terminal is back in service or otherwise ready to
`receive messages.
`Anotherdifference between SMS and the common one-waypageris
`that with traditional paging services one never knows exactly if or when
`messages really arrive at the addressee, whereas with GSM, one can
`receive confirmation ofthe arrival of each message. In the unfortunate
`case where a message doesnotarrive within a specified time, the sender
`will be notified. There is an optional service for notification of when a
`message actually does arrive at the mobile phone.
`Point-to-point short messagesuse a dedicated link, as in a voice call,
`on a duplex radio channel. This has the advantage that the network and
`the mobile station actually talk to each other, thus error handling mecha-
`nisms make sure that a message arrives properly at the recipient’s mobile
`station and is stored properly therein. If this is not the case orif the
`mechanism fails for any reason, an error messagewill be created by the
`mobile station notifying the network of the problem together with the
`reason why a message wasnot received correctly. Since this message link
`uses a different service access point identifier (SAPI) than speech,it is even
`possible to send a message to a phonethatis already carrying normal
`voice traffic for the recipient.
`
`Short message service
`
`Another advantageover. for
`cost: when compared to a voice
`stored during a charged voice ca!
`chargedvoicecall, direct short =
`Wayofgetting quick and short &
`The term short message comes
`individual message, which is liz
`140 bytes) for each single messag
`to-point SMScan be found in {1}
`
`Implementation
`6.1.1
`point-to-point SMS in ¢
`network
`
`To clearly describe the message f
`depicted in Figure 6.1 andis dese
`(SME) is, in general, the device tt
`be:
`
`» A mobilestation. In this case’
`sage between two mobile stz
`tions do not necessarily haw
`SMSis transparentto user h
`
`D A computer directly connected
`provided by the operator, w
`and requesting a message te
`
`D A device or computer located im:
`allows someoneto dial dires
`message.
`
`> A computerthat delivers updame
`service the user subscribes to
`request. This should not be e
`always without request.
`
`The SC handlesall functions re
`receives a message from a SME and
`not reach the addressee,it stores th:
`specified by the useror the operates
`
`ieee
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`213
`
`Anotheradvantageover, for example, leaving voice mail messagesis
`“est: when comparedto a voice mail service, for which the messageis
`stored during a charged voicecall and has to be retrieved by yet another
`chargedvoicecall, direct short messagingis by far the most economical
`way ofgetting quick and short information to the right destination.
`The term short message comes from the relatively short length of each
`dividual message, which is limited to 160 characters (mapped onto
`140 bytes) for each single message. The technical specification for point-
`to-point SMScan be foundin [1].
`
`6.1.1 Implementation of
`point-to-point SMS in the
`network
`
`To clearly describe the messageflow, the relevant networkstructure is
`depicted in Figure 6.1 andis described as follows. The short message entity
`(SME)is, in general, the device that originates a short message. It might
`be:
`
` Short message service
`
`» A mobilestation. In this case we observe the transmission of a mes-
`sage between two mobile stations. By the way, the two mobilesta-
`tions do not necessarily have to be roaming in the same network;
`SMSis transparentto userlocations.
`
`» A computerdirectly connectedto the service center (SC). This is a service
`provided by the operator, which can be used simply by dialing in
`and requesting a message to be sent to a specific subscriber.
`A device or computerlocated in thefixed network. The special computer
`allows someonetodialdirectly into the SC in order to dispatch a
`message.
`
`A computer that delivers updated news services. This is an example of a
`service the user subscribes to and to which she makes somekindof
`request. This should not be confused with cell broadcast, which is
`always withoutrequest.
`
`The SC handlesall functions related to point-to-point SMS. The SC
`receives a message from a SME and forwardsit to the addressee. If it can-
`not reach the addressee,it stores the message up to some maximum time
`specified by the user orthe operator.If necessary,or if requested, the SC
`
`
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

`214
`
`GSM and Personal Communications Handbook
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Figure 6.1 Network entities involved in the provision of short
`messages.
`
`notifies the sender about the successful or unsuccessful delivery of a mes-
`sage. The SC,by definition, is not part of the GSM PLMN.In actual prac-
`tice it is integrated into or connected to the MSC.
`WhenSMSservicesfirst started it was commonfor there to be only
`one service center per operator. However, with the increasing numberof
`applications for short messages, an operator would needseveralservice
`centers to handleall of the messages. Thisis, for example, the case if one
`center were to handle the SMSfor standard text messages between two
`subscribers, and another center handles a kind of service where the user
`sends a message to the SC requesting the latest result of a Formula 1 car
`race or thelatest stock exchange information. This secondset of examples
`is similar to faxback services.
`It is also possible, on the other hand, for one SC to serve several
`PLMNs. This would be the case, for example, when twooperators in one
`country share an SC, or two operatorsin different countries share an SC.
`Oneservice center might be connected to several MSCs.
`switching center
`The short message service-gateway mobile services
`(SMS-GMSC) is a dedicated function within a MSC that allows it to
`receive a short message from theSC,investigate the attached home location
`register (HLR) in order to find out where the recipient mobile station is
`currently located, and then deliver the short message to the visiting MSC
`and, eventually, to the mobile station. The SMS-GMSC function is used
`when a mobile station is the recipient of the message. This is represented
`in Figure 6.1 by a mobile-terminated short message, which would flow
`from left to right in the figure.
`The short message service-interworking mobile services switching center
`(SMS-IWMSC) is another dedicated function within a MSC that allows
`
`Short message service
`
`the SC to receive short mess
`the mobile station is the ors
`message to the recipients '
`mobile-originated SMS.
`SMS-GMSC and SMS-!
`warding of short messages.
`information between the x
`example, the exchange of
`The homelocation register
`the subscribers belonging ©
`relevant data in the HLR is’
`mobile station, and (2) whe
`
`messages.
`The mobile services switch
`tem. Withall of its registers.
`via the mobile network. to
`connections to other entitte
`
`mation about the current w
`needed in order to forward
`The visitor location regis
`mobile stations of the ser
`datum is the more precise p
`is located.
`The base station subsystem
`over the radio (U,,) interias
`The mobile station (MS).
`or a recipient of a short me
`the network about abnor
`
`overflow.
`
`6.1.1.1 Functions and
`
`Short message serviceis bas
`service center, the HLR. the
`ters. Depending on the Gi
`taining the message accom
`course, other message fram
`such as a status report amd:
`carrying the actual user dat
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`Short message service
`
`215
`
`the SC to receive short messages from the MSC. This would bethecaseif
`the mobile station is the originator of a short message. It then submits the
`message to the recipient’s service center. The SMS-IWMSC is used for
`mobile-originated SMS.
`SMS-GMSC and SMS-IWMSC arenotonly responsible for the for-
`warding of short messages, but in general for the complete exchangeof
`information between the network and the SMSC, which includes, for
`example, the exchangeof status messages, as described later.
`The homelocation register (HLR) stores the identity and userdataofall
`the subscribers belonging to the area of the related MSC. For SMS, the
`relevantdata in the HLRis (1) the current location (MSC) ofthe recipient
`mobile station, and (2) whetherit is switched on andavailable to receive
`messages.
`The mobile services switching center (MSC) is a complete exchangesys-
`tem. Withallof its registers,it is able to route calls from the fixed network,
`via the mobile network, to an individual mobile station. The MSC has
`connectionsto otherentities of the PLMN,whichallowit to gatherinfor-
`mation about the current whereabouts of a mobile station; the locationis
`neededin order to forward messages.
`The visitor location register (VLR) containsall relevant data onvisiting
`mobile stations of the serving MSC. In the case of SMS, the relevant
`datum is the more precise paging area wheretherecipient mobilestation
`is located.
`The base station subsystem (BSS) is used asa transport vehicle for SMS
`over the radio (U,,) interface.
`The mobile station (MS), in the particular case of SMS,is either a sender
`or a recipient of a short message. The mobile station would also inform
`the network about abnormal(erroneous) situations, such as memory
`overflow.
`
`carrying the actualuser data, which will appearon the display of a mobile
`
`6.1.1.1 Functions and parameters of point-to-point SMS
`Short messageservice is based on functionality thatis distributed over the
`service center, the HLR, the VLR, and the MSC with a numberof parame-
`ters. Depending on the direction of transmission, the data frame con-
`taining the message accommodates different parameters. There are, of
`course, other message frames supporting different functions of the SMS,
`suchas a status report and a command. Here wediscuss only the frames
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

`Short message service
`
`can be the case when a mobile
`The basic principle behind thi
`should be delivered in one go
`established. This not only reduc
`the radiointerface, but also in
`tion and ciphering procedures «
`The message type indicator (M
`message contained in the frame
`
`» Delivering a short messag
`and the corresponding om
`
`\» Submitting a short messag
`‘ andconfirmation of the =
`»\Statuis report from the m
`whereaboutsof a previow
`
`» Issuing a command from |
`
`This last command issued
`invoke an operationor inquiry2
`previously sent short message «
`status report request.
`Table 6.1 lists the different w.
`and their meanings.
`
`Ta
`List of Valmes
`
`Value
`Direction
`
`
`00
`
`00
`
`Network—Ms
`
`MS-network
`
`01
`01
`
`Network—MS
`MS-network
`
`
`
`ROms
`10
`Network-MS
`max. 140=~~*~ user Data
`ee ese
`10
`MS-network
`
`216
`
`GSM and Personal Communications Handbook
`
`station when a mobile terminated SMStransaction is completed success-
`fully. In the otherdirection we have mobile originated messageservices,
`which are initiated by messages generated in the mobile phone.
`The messages described here are higher layer messages. Additional
`information must be added to the messages before they can be trans-
`ported onthe air interface. Furtherdetails are found in [2].
`
`Figure 6.2 showsthestructure and format
`SMS-MT message frame
`of a short message-mobile terminated (SM-MT) message frame with thedif-
`ferent fields and parameters. The reply path (RP) flag indicates that an
`answerfor this specific messageis paid by the originatorof the message,
`and the recipient can answerfree of charge. Sometimesit is sufficient to
`get a simple yes or no reply to a short message, such as, “Should we meet
`todayat 12:00?” Thereply path option has been defined for this purpose.
`This gives the recipient the ability to send a short answer without having
`to pay anythingfor this service. In GSM SMS,this option is invoked by the
`senderof the short message.
`Thestatus report indication (SRI) shows that a status report will be sent
`back to the originator (SME)ofthis short message. This meansthat the
`report of properdelivery from the mobile station will be passed on to the
`originator as confirmationof delivery of the short message.
`The more-messages-to-send (MMS)flag indicatesthat, for this particular
`recipient, several messages are waiting to be deliveredin the SMSC. This
`
`#.6-6:4°3 21-0
`Bit No.
`Octet No. 1(_JOlTofol[| RP, SRI, MMS, MTI
`
`ee ee max. 12
`
`Time StampWe
`
`Originating Address
`
`Protocol Identifier
`Data Coding Scheme
`
`Service Center
`
`User Data Length
`
`Figure 6.2 Format of an SM-MT,
`
`1]
`
`Any
`
`
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`Short message service
`
`217
`
`» Delivering a short message from the network to the mobilestation,
`and the corresponding confirmation from the mobile station;
`
`> Submittinga shortmessagefromthe mobilestationtothe ieee,
`
`and confirmation of the network;
`
`heof
`
`» Status report from the network to the mobile station about the
`whereabouts of a previously sent message;
`
`» Issuing a commandfrom the mobile station to the network.
`
`This last commandissued by the “subscriber” enables the MS to
`invoke an operation or inquiryat the SC, which could be the deletion ofa
`previously sent short message or the cancellation or initialization of a
`status report request.
`Table 6.1 lists the different values for the message type, the direction,
`and their meanings.
`
`Table 6.1
`List of Values for the Message Type
`
`Value
`
`Direction
`
`Message Type
`
`00
`00
`
`Network-MS
`MS-network
`
`Delivery of a short message from the network
`Report on delivery of short message from the
`mobilestation
`
`can be the case when a mobile station was switched off for a long time.
`The basic principle behind this is that all messages awaiting delivery
`should be delivered in one go oncethesignaling channel link has been
`established. This not only reducessignaling effort andtraffic (air time) on
`the radio interface, but also in the networkitself since all the authentica-
`tion and ciphering procedures are only performed once.
`The message type indicator (MTI) is a 2-bit value describing the kind of
`message contained in the frame. The messagetypeis relatedto:
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Sending ofa status report from the network
`Network-Ms
`01
`
`
`Sending of a command from the mobile station
`MS-network
`Ol
`
`Submission of a short message from the mobile
`Network-MS
`10
`station
`
`10
`MS-network
`Report on delivery of short message from the
`network
`
`_EE
`
`
`
`Any
`
`Reserved value
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

`218
`
`GSM and Personal Communications Handbook
`
`Short message service
`
`| Value
`
`12
`13
`
`Telematic Device
`
`Teletex in digital ISDN Gaeae
`Universal computer imterisc= |
`
`14-15
`
`Reserved (two combimsmans
`
`Message handling facility ===
`Any public X.400-based mess
`
`Values specific to each S=rvaes
`
`16
`17
`18-23
`
`31
`
`Reserved (six combins=am=) 24-30
`
`The originating address (OA) contains the address of the senderof a
`specific message. If the sender was another mobilestation, then the origi-
`nating address is the actual phone numberof a specific mobilestation.
`Many mobile phones nowadaysrealize that this address is a phone
`number, and allow the user to select this number in orderto call the
`numberdirectly, or respond with anothershort message. Thefirst option
`is especially helpful if the user wants to talk to the person whosentthe
`message rather than respond with another short message.
`The protocolidentifier (PID) instructs the service center in which for-
`mat or protocol the short message should be delivered. There are two
`major distinctions. Oneis the transfer of a short message between two
`mobile phones within the GSM infrastructure, which requires no special
`treatment becauseit uses only the higherlayers. The otheris the use of
`telematic interworking whena short messagehasto be “translated”into
`another format. The user of a mobile telephoneis entitled to set up the
`protocolidentifier. Note, however, that not all networks supportthe dif-
`ferent protocols since these always require additional hardware in the
`network. See Table 6.2 for the different values for the protocolidentifiers
`in telematic interworking. As should be obviousfrom thelist,it is, in prin-
`ciple, possible to transfer a short message into a message for any kind of
`device.
`
`Table 6.2
`Values for the Protocol Identifiers Used for SMS
`
`Telematic Device
`
`Implicit, the device typeis specific to this service center or can be deduced
`from the basis of the address
`
`Telex (or teletex reducedto telex format)
`Group 3 telefax
`
`Group 4 telefax
`
`Voice telephone(i.e., conversion to speech)
`ERMES (European Radio Messaging System)
`National Paging System (as it is known to the service center)
`Videotext (T.100/T.101)
`
`Teletex, carrier unspecified
`
`
`
`Teletex in PSPDN (public-switched packet data network)
`
`Teletex in CSPDN (cellular-switched packet data network)
`
`Teletex in analog PSTN (public-switched telephone network)
`
`Value
`
`0
`
`—=
`omvAoOoafFOOhe
`
`
`
`received alphabet co
`station (e.g., the default one)
`
`The data coding scheme (DCS) im
`decodingis used for the alphabet &
`two alphabets are available: (1) @
`These are specified in Section 6.1.2
`also specifies the class of the short
`Theservice center time stamp (SC
`arrived at the service center. This ®
`Each mobile phone user can see. 5
`message wasactually sent, or, to be
`received it. From this time stamp, o
`took the network to deliver the m
`is in the Year:Month:Day:HourM
`value is represented by two digits.
`The user data length (UDL) indice
`characters. The lengthis, therefore
`the 8-bit coding schemeis used.
`of octets. If the default (7-bit cae
`numberofoctets is less than the @
`The user data (UD) contains the
`mum length of 140 octets. Section
`the codingof the individual charac
`short message contains up to 1602
`mum of only 140 octets. In Sect
`shown along with the coding of
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`Short message service
`
`219
`
`
`Value
`Telematic Device
`|
`
`12
`Teletex in digital ISDN (integrated servicesdigital network)
`}13
`Universal computerinterface (UCI) as specified in ETSI DE/PS 3 01-3
`14-15
`Reserved (two combinations)
`16
`Message handlingfacility that is known to the service center
`17
`Any public X.400-based message system
`18-23
`Reserved(six combinations)
`24-30
`Valuesspecific to each service center; the usage is based on mutual
`agreement betweenthe short message entity and the service center(there
`are seven combinations available for each service center)
`GSM mobile station. The service center converts the short message from the
`received alphabet coding to any alphabet decoding supported by that mobile
`station (e.g., the default one)
`
`31
`
`
`
`Thedata coding scheme(DCS)informsthe mobile station about which
`decoding is used for the alphabetused in the actual message. Currently,
`two alphabets are available: (1) the default alphabet or (2) 8-bit data.
`These are specified in Section 6.1.2. In addition to the alphabet, the DCS
`also specifies the class of the short message.
`Theservice center time stamp (SCTP) indicates when a specific message
`arrived at the service center. This timeis also deliveredto the recipient.
`Each mobile phoneusercansee, by this time stamp, whenthereceived
`message wasactually sent, or, to be more precise, when the service center
`receivedit. From this time stamp,
`one could actually evaluate how longit
`took the network to deliver the message. The formatof the time stamp
`is in the Year:Month:Day:Hour:Minute:Second:Time zone order. Each
`value is represented by two digits.
`The userdata length (UDL) indicates the length ofthe followingdata in
`characters. The lengthis, therefore, dependent on the coding scheme.If
`the 8-bit coding schemeis used, then the UDLis identical to the number
`of octets. If the default (7-bit coded)
`GSM alphabetis used, then the
`numberofoctets is less than the numberof characters.
`The user data (UD) containstheactual encoded message with a maxi-
`mum length of 140 octets. Section 6.1.2 describes the GSM alphabet and
`the codingofthe individual characters, This reveals the mystery of why a
`short message contains up to 160 characters, but can becarried by a maxi-
`mum of only 140 octets. In Section 6.1.3 a complete message will be
`shownalong with the coding of the userdata.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

`220
`
`GSM and Personal Communications Handbook
`
`Short message service
`
`The validity period (VP) im
`SMS-MO message frame_Figure 6.3 showsthe structure and for-
`valid, and how long the SC s&
`matof a short message—mobile originated (SM-MO) message with thediffer-
`entfields and parameters. The RP indicates that the sender of the message
`Let’s say we sent an urgent sb
`is willing to pay for the response.
`this evening. It would not mal
`The status report request (SRR) indicates that the senderof this short
`this message tomorrow mor
`message wants to have a confirmation that the message wasdelivered.If
`different formats: the relative
`the message was delivered within the validity period, then the senderwill
`get a positive confirmation along with the time when the message was
`delivered. All of this will appear within a status report explained in the
`paragraph about the message type.If the message could not be delivered,
`then the sender would be notified aboutthis fact along with a causevalue.
`Thevalidity periodformat (VPF) describes whetherthevalidity periodis
`present in this message, andif it is present, whetherit is represented as a
`relative or an absolute value.
`The messagetype indicator (MTI)is identical to the one describedin the
`chapter on supplementary services, Chapter7.
`The message reference (MR) allows the mobile station to numberthe
`short messages that have been sent. This MR is used whena status report
`is issued to the mobile station by the service center.
`The destination address (DA) indicates the recipient of this short mes-
`sage. The addressis entered as a normal phone number. The PID and the
`DCS are, again, identical to the mobile-terminated message.
`
`In the case of the absolut
`time stamp.The absolute vali
`sage. In the relative represe:
`frames decreases with increa
`validity periods up to 12 hou
`decreases to 30-minute steps
`1 week, the resolution decree
`1 week up to 63 weeks (more:
`reality, however, the long vali
`indications are mostly theore
`tend to limit validity times
`limits the amountof expemsi
`messages.
`The UDL and UD are simi
`
`Bit No.
`Octet No.
`
`mae 12
`
`
`
`RP, SRR, VPF, MTI
`Message Reference
`
`Destination Address
`
`Protocol Identifier
`
`User Data Length
`
`Additional functionality i
`considered specific messages
`received from them. We have:
`sages are sent and howthe ne
`details become important,
`|
`switched off or move out of
`Consider a message that &
`Whenthepriority indicator for
`ter continuously tries to delivs
`as “no memoryavailable,” ism
`Data Coding Scheme
`station is temporarily absent
`1 or7 —__|Validity Period
`condition is cleared. Sending =
`chances of early delivery: t
`return of a mobile station to se
`clear his short message mMemor
`Whenthe SMScould nott
`
`max. 140 Eo UserData
`
`n
`
`Figure 6.3 Format of an SM-MO.
`
`available in the VLR as the ma?
`as message-waiting-data field. »
`
`
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

` Short message service
`
`221
`
`The validity period (VP) indicates how longa specific short message is
`valid, and howlong the SC should,therefore, try to deliver the message.
`Let's say we sent an urgent short message indicating an appointmentfor
`this evening. It would not make muchsenseto try continuously to deliver
`this message tomorrow morning. Thevalidity can be represented in two
`different formats: the relative validity and the absolute validity.
`In the case of the absolute validity, the formatis identical to the SC
`time stamp. Theabsolutevalidity specifies the “expiration date” of a mes-
`sage. In the relative representation of validity, the resolution of time
`frames decreases with increasing time. The resolution is 5 minutes for
`validity periods up to 12 hours. From 12 hours to 1 day the resolution
`decreases to 30-minute steps. For validity periods between 1 day and
`1 week, the resolution decreases even further to a whole day; and from
`1 week up to 63 weeks (more than a year) it decreases to 1-weeksteps. In
`reality, however, the longvalidity periods with low-resolution expiration
`indications are mostly theoretical curiosities because network operators
`tend to limit validity times to a maximum of several days. Doingthis
`limits the amountof expensive network resources required for storing
`messages.
`The UDL and UDaresimilar to the mobile-terminatedcase.
`
`So far we have only
`Additional functionality in the network
`considered specific messages that were sent out to mobile stations or
`received from them. We havenotyet explored thedetails of how the mes-
`sages are sent and howthe networkensurestheir proper delivery. These
`details become important,
`for example, when mobile phones are
`switched off or move out of reach of the network.
`Consider a message that is waiting in the service centerfor delivery.
`Whenthepriority indicator for such a messageis set, then the service cen-
`ter continuously tries to deliver the message even thoughanerror, such
`as “no memoryavailable,” is returned from the target mobile, the mobile
`station is temporarily absent, or the HLR does not confirm that an error
`condition is cleared. Sending the short message moreoften increases the
`chances of early delivery; there are more opportunities to detect the
`return of a mobile station to service, or thatthe user hasfinally decided to
`clear his short message memory, either in the phoneorin the SIM card.
`Whenthe SMScould not be delivered, the messages waiting elementis
`available in the VLRas the mobile-station-not-reachable flag, and in the HLR
`as message-waiting-data field, which is further subdivided into different
`
`
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

`222
`
`GSM and Personal Communications Handbook
`
`Short message service
`
`the validity period, am
`message was received
`protocol, it checks wh
`sent to the same addre
`
`message.
`
`3. The SC notifies the SM
`
`a mobile station. lithe:
`then the MSC will pass
`the recipient.
`
`4. The SMS-GMSC asks ©
`tion is currently locat
`currently not available
`occured (see Section 6.
`HLR will set a flag that
`not successful. This sits
`ery is finally successful
`
`is
`conditions. The implementation in the VLR is mandatory, and it
`optional in the HLR.If a delivery attemptof a short message was unsuc-
`cessful, then the network will return some diagnostic results. If the
`mobile station is not available, then the mobile-station-not-reachable flag is
`set in the VLR.If the mobile station becomesalive again, or becomesoth-
`erwise accessible by the network, the VLR will notify the SC ofthis happy
`event through the HLR. Othererror cases will generate an entry into the
`optional message-waiting-data field in the HLR.If this is not present, the
`option to includeit in the HLR hasnot been exercised, and then the SC
`would simplyreceivea failure indication. The SC,then,is obliged to cope
`with failure indicationsitself. Even thoughitis optional, the assistance of
`the HLRis a more effective way to deal with erroneous message deliver-
`ies. As soon asthe HLRdetects that a problem is resolved,it notifies the SC
`with thealert-SC command.In the message-waiting-datafield,thereis suffi-
`cient room to enter the addresses of multiple service centers that have to
`be notified when problemsare resolved.
`The mobile-station-not-reachable flag and the message-waiting-data field
`will only beclearedif all messages have been sent successfully to a mobile
`5. With the MSC’s know
`station. This data management scheme makessure thatall messages
`recipient mobile statio
`arrive at the mobile properly.
`sage on to the visited 3
`The service center can also sendastatus report to the originatorof a
`message. The status can be simply that a message was successfully deliv-
`6. The visited MSC checks
`ered to the SME. Therequestfor this status message can be invoked by the
`originator with a dedicated requestforthis status report within the short
`message. On the other hand, a status report can also be issued when a
`message could not bedeliveredto the recipient. The implementationof
`this status report capability is optional, andisleft entirely to the operator.
`
`tion area the mobile st
`
`7. The BTSs in the locatios
`tered, page the mobile
`channel and delivers
`
`6.1.1.2
`SMS MT
`In the case of mobile-terminated SMS, where the message will arrive in
`the mobile station, the following steps will take place:
`
`1, The short message is generated in the SME. It does not matter
`whetherthe SMEis another mobilestation or an entity within the
`PLMN.
`
`2. The short message is sent from the SMEto theservice center. The
`service center controls further handling of the message. It checks
`
`8. The mobile terminal n
`been received. The not
`visual] signal that may|
`
`Figure 6.4 showsthe displ
`short message. A problem that
`size of the display is not big ems
`mobile station, therefore, has +
`sages and provide a meansfort
`the messageitself, there is lots «
`
`FORDEX. 1018
`
`FORD EX. 1018
`
`

`

`GSM and Personal
`Communications Handbook
`
`SiegmundM. Redl
`Matthias K.Weber
`Malcolm W.Oliphant
`
`MH
`
`Artech House
`Boston ¢ London
`
`
`
`
`
`FORD EX. 1018
`
`FORD EX. 1018
`
`

`

` Library of Congress Cataloging-in-Publication Data
`
`
`
`
`
`
`
`
`
`
`Redl, Siegmund M.
`GSMandpersonal communications handbook / SiegmundRedl,
`Matthias Weber, Malcolm Oliphant
`p.
`cm, — (Artech House mobile communicationslibrary)
`Includes bibliographical references and index.
`ISBN 0-89006-957-3 (alk. paper)
`2. Personal
`1. Global system for mobile communications.
`communication service systems.
`I. Weber, Matthias K.
`II. Oliphant, Malcolm W.
`Il. Title.
`IV. Series
`TK5103.483.R44
`1998
`621.3845'6—dc21
`
`
`
`
`
`
`
`
`
`
`
` Contents
`
`
`
`98-4710
`CIP
`
`
` British Library Cataloguing in Publication Data
`
`
`
`
`
`
` ‘Petl GSM in the ightot
`nj Thechangingscene
`Li The dota coli
`iz Bassc market ign
`IZ] Cemadpe
`Gozte preseoce aud;
`122 Mectno Sede
`
`Redl, Siegmund M.
`GSMandpersonal communications handbook—(Artech House mobile
`communicationslibrary)
`1. Global system for mobile communications
`I. Title
`II. Weber, Matthias K.
`III. Oliphant, Malcolm W.
`621.3'8456
`
`
`
`
`ISBN 0-89006-957-3
`
`
`
`Cover and text design by Darrell Judd.
`
` © 1998 ARTECH HOUSE, INC.
`
`685 Canton Street
`
`
`
`
`
`
`
`
`
`
` i4 Phones stunkihe
`
`
`Norwood, MA 02062
`
`
`
`All rights reserved. Printed and boundin the United States of America. No part of
`this book may be reproducedorutilized in any form or by any means,electronic or
`mechanical, including photocopying, recording, or by any information storage and
`retrieval system, without permission in writing from the publisher.
`All terms mentioned in this book that are knownto be trademarks orservice
`marks have been appropriately capitalized. Artech House cannotattest to the a