(12) United States Patent
`Forslöw
`
`USOO6608832B2
`(10) Patent No.:
`US 6,608,832 B2
`(45) Date of Patent:
`*Aug. 19, 2003
`
`(*) Notice:
`
`(54) COMMON ACCESS BETWEEN A MOBILE
`COMMUNICATIONS NETWORKAND AN
`EXTERNAL NETWORK WITH SELECTABLE
`PACKET-SWITCHED AND CIRCUIT.
`SWITCHED AND CIRCUIT-SWITCHED
`SERVICES
`(75) Inventor: Jan E. Forslöw, Menlo Park, CA (US)
`(73) Assignee: Telefonaktiebolaget LM Ericsson,
`Stockholm (SE)
`This patent issued on a continued pros-
`ecution application filed under 37 CFR
`1.53(d), and is subject to the twenty year
`patent term provisions of 35 U.S.C.
`154(a)(2).
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`(21) Appl. No.: 09/121,678
`(22) Filed:
`Jul. 23, 1998
`O
`O
`(65)
`Prior Publication Data
`US 2003/0039237 A1 Feb. 27, 2003
`Related U.S. Application Data
`(60) Provisional application No. 60/060,061, filed on Sep. 25,
`1997.
`(51) Int. Cl." ................................................ H04L 1266
`(52) U.S. Cl
`370/353; 370/229; 370/328
`(58) Field of Search ................................. 370/353, 351,
`370/352, 389, 395.1, 400, 401, 402, 354-357,
`360, 229, 230-231, 235, 310, 328-329,
`335-336,345, 347, 395.2, 395.21, 395.3,
`395.4, 395.42, 395.52, 437, 465, 466,486,
`487; 455/403, 410, 411, 575
`References Cited
`U.S. PATENT DOCUMENTS
`5,790,534 A * 8/1998 Kokko et al. ............... 370/335
`(List continued on next page.)
`
`(56)
`
`FOREIGN PATENT DOCUMENTS
`07894. A
`81997
`(List continued on next page.)
`OTHER PUBLICATIONS
`H. Schulzrinne et al., Network Working Group, Request for
`Comments: 2326, Category: Standards Track, Apr. 1998,
`“Real Time Streaming Protocol'.
`(List continued on next page.)
`Primary Examiner Douglas Olms
`ASSistant Examiner Brian Nguyen
`(74) Attorney, Agent, or Firm Nixon & Vanderhye P.C.
`(57)
`ABSTRACT
`Applications running on a mobile Station or an external
`network entity Such as an Internet Service provider may
`Specify on an individual application flow basis a requested
`quality of Service. From that requested quality of Service, an
`optimal type of bearer to transfer the application flow
`through the mobile communications network is determined.
`For example, a circuit-Switched bearer may be allocated if
`the request is for a real-time Service, and a packet-Switched
`bearer may be allocated if the request is for a non-real time
`type of Service. Various other decision making criteria may
`be employed. A mobile Station and a mobile network gate
`way node each include a mapper for mapping an individual
`application flow to one of a circuit-Switched network and a
`packet-Switched network bearer depending on the quality of
`Service requested for the individual application flow. The
`network layer quality of Service parameters corresponding to
`an individual application flow are mapped to circuit.
`Switched bearer parameters if the application flow is mapped
`to the circuit-Switched network and to packet-Switched
`bearer parameters if the application flow is mapped to the
`packet-Switched network. The gateway node includes a
`common access Server which permits a mobile Station
`initially establishing a communications Session with an
`external network entity to perform only a Single, common
`acceSS procedure for Subsequent communications using one
`of the circuit-Switched and packet-Switched networks. After
`that common acceSS procedure is completed, Subsequent
`application flows between the mobile Station and the exter
`nal network entity are established using abbreviated proce
`dures without having to access the external network entity.
`60 Claims, 12 Drawing Sheets
`
`30
`
`35
`
`". 32
`4.
`t
`
`I
`N
`BSc
`
`38
`
`PSTN,
`ISDN, etc.
`
`42
`
`HR
`
`El 36
`SS
`40
`7
`Network
`
`50 so
`
`46 44
`
`GSM
`CIRCUIT-SWITCHEO
`Network
`
`SGSN
`
`Intra-PLMN
`PBackbone
`
`GGSN
`
`52
`
`GSM GPRS (PACKETSWITCHED) Network
`
`56
`
`
`
`5i
`
`P Data
`Network
`
`58
`
`internet
`Service
`Provider
`(ISP)
`
`Ex.1011
`APPLE INC. / Page 1 of 28
`
`

`

`US 6,608,832 B2
`Page 2
`
`U.S. PATENT DOCUMENTS
`
`5,852,718 A 12/1998 Van Loo ..................... 709/208
`5.991.292 A * 11/1999 Focsaneanu et al. ........ 370/352
`6,081,517 A * 6/2000 Liu et al. ..........
`... 370/352
`6,094,581. A * 7/2000 Fried et al.
`... 455/449
`6,097.733 A * 8/2000 Basu et al. ....
`... 370/329
`6,122.263 A
`9/2000 Dahlin et al. ............... 370/329
`6,157,648 A 12/2000 Voit et al. ................... 370/401
`FOREIGN PATENT DOCUMENTS
`
`
`
`WO
`WO
`WO
`
`9/1995
`95/25407 A
`3/1996
`96/09708 A
`97/47112 A 12/1997
`
`OTHER PUBLICATIONS
`C. Rigne, Network Working Group, Request for Comments:
`2139, Obsoletes: 2059, Category: Informational, Apr. 1998,
`"Radius Accounting”.
`R. Braden et al., Network Working Group, Request for
`Comments: 2205, Category: Standards Track, RFC 2205,
`Sep. 1997, Resource ReServation Protocol (RSVP)-Ver
`Sion 1 Functional Specification.
`R. Droms, Network Working Group, Request for Com
`ments: 2131, Obsoletes: 1541, Category: Standards Track,
`Mar. 1997, “Dynamic Host Configuration Protocol”.
`
`C. Rigney et al., Network Working Group, Request for
`Comments: 2138, Obsoletes: 2058, Category: Standards
`Track, Apr. 1997, “Remote Authentication Dial In User
`Service (RADIUS)”.
`W. Simpson, Network Working Group, Request for Com
`ments: 1661, STD: 51, Obsoletes: 1548, Category: Stan
`dards Track, Jul. 1994, “The Point-to-Point Protocol
`(PPP)”.
`H. Schulzrinne et al., Network Working Group, Request for
`Comments: 1989, Category Standards Track, Jan. 1996,
`“RTP: A Transport Protocol for Real-Time Applications”.
`Michael Patrick, DHC Working Group, Nov. 24, 1997,
`“DHCP Relay Agent Information Option”.
`A. Valencia et al., PPP Working Group, INTERNET
`DRAFT,
`Category:
`Internet
`Draft,
`Title:
`draft-iet? pppext-12tp-11.txt, May 1998, “Layer Two Tun
`neling Protocol L2TP".
`O. Gudmundsson et al., DHC Working Group, Internet
`Draft, Mar. 1998, “Security Requirements for the DHCP
`Protocol.
`
`* cited by examiner
`
`Ex.1011
`APPLE INC. / Page 2 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 1 of 12
`
`US 6,608,832 B2
`
`
`
`
`
`
`
`
`
`|
`
`Ex.1011
`APPLE INC. / Page 3 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 2 of 12
`
`US 6,608,832 B2
`
`
`
`
`
`
`
`Sg
`
`Cl2 -
`9 O.
`ce a CO
`
`W. Nea
`
`i
`
`o
`
`
`
`
`
`
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 4 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 3 of 12
`
`US 6,608,832 B2
`
`
`
`ŒT
`dl/d01—ºff - 400NS
`
`OTTÁ0|0}} OTT
`
`Ex.1011
`APPLE INC. / Page 5 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 4 of 12
`
`US 6,608,832 B2
`
`Fig. 4
`
`
`
`Optimal Bearer Select
`
`60
`
`61
`
`MS registers with mobile COmmunications
`System
`
`Application requests One Ormore quality OfService
`(QOS) parameters for One Ormore individual application flows.
`
`
`
`Based On requested QoS for a specific flow, select Optimal
`One of a circuit-switched (CS) and a packet-switched (PS)
`bearer to Carry a Specific flow.
`
`62
`
`64
`
`66
`
`Map requested QOS parameters to bearer parameters
`Of the Selected bearer.
`
`
`
`CONTINUE
`
`
`
`
`
`
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 6 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet S of 12
`
`US 6,608,832 B2
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 7 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 6 of 12
`
`US 6,608,832 B2
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 8 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 7 of 12
`
`US 6,608,832 B2
`
`F18. 8
`
`Bearer Select and QoS Map
`
`70
`
`72
`
`Detect an application flow, a flow identifier Or Service class,
`and aSSOciated Plevel QOS parameters
`
`ls Play Bay.
`not present, below, above,
`or inside threshold
`(T) range?
`is Bucket Depth
`not present, below, above,
`Or inside threshold (T)
`range?
`
`AbOve
`
`Below
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`is Service Class = not present,
`guaranteed, COntrolled load,
`best efforts?
`
`Within T
`
`Not Present
`
`Best Efforts (>
`is TTL not present,
`below, als inside T
`cored Not Present
`
`Is Volume (TTLXMBR)
`not present, below, above,
`Orinside Trange?
`
`Modify existing Orestablish new
`packet-switched (PS) bearer.
`Map IP QOS parameters to PS
`bearer QoS parameters.
`
`
`
`Not Present
`
`86
`
`Modify existing Orestablish new
`circuit-switched (CS) bearer.
`Map IP QoS parameters to CS
`bearer QoS parameters.
`
`CONTINUE
`
`Ex.1011
`APPLE INC. / Page 9 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 8 of 12
`
`US 6,608,832 B2
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 10 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 9 of 12
`
`US 6,608,832 B2
`
`Fig. 10
`SGSN
`
`MSC/DAU
`
`GGSN/AS
`
`
`
`Server
`
`
`
`
`
`
`
`An ISP relationship is
`established and the MS has
`already received SOme
`application Control packets
`Over the GPRS bearer.
`
`
`
`
`
`
`
`
`
`
`MSEA
`eStatDIS eS a
`Cal tyard the
`
`RLC(PPPPDU)
`MScecides to end
`the Calland release
`the CS bearer
`
`LLC (PPDU)
`
`GGSN selects Optimal PS/CS
`bearer and RTP coding based
`On MS profile, MS class and
`IP packet header information.
`The GGSN decides to set-up
`a CS Call towards the MS
`for the real-time flow.
`
`L2TP Outdoing Call Request
`{Dialled No = MSid, Calld,
`Bearer Service Type...}
`GGSN Selects transfer
`mechanism for the
`incoming packets. Although
`non-realtime, the packets
`are forwarded along
`the CS bearer as the MS
`Class = Barda CS
`COnnection is established with
`Bearer ServiceType = data.
`L2TP(PPPPDU)
`MSid, Calid.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`L2TP DisCOnnect Notif
`{MSid, Callid.}
`GPRS service is preferred
`for the incoming packets
`and now possible to use.
`
`
`
`Realtime IP Packets
`ransport Protocol,
`Port No.}
`
`Non-reatime IP
`Packets
`Transport Protocol,
`Port No...)
`
`Non-realtime IP
`Packets
`{Transport Protocol,
`Port No...)
`
`{TID=MSid + NSAPI.)
`CS and PS Bearer Service Selection
`
`Ex.1011
`APPLE INC. / Page 11 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 10 of 12
`
`US 6,608,832 B2
`
`Fig.11
`
`COmmOn External NetWOrk ACCeSS
`
`170
`
`When MS establishes a session with the mobile network,
`i.e., registers, perform a COmmOn access procedure at a mobile
`gateWaynOde.
`
`Perform a Common authentication procedure
`for both circuit-switched(CS) and packet-switched (PS)
`bearer Services. Store authentication parameterS.
`
`Perform One IPhost/MS Configuration for
`both CS and PS bearer Services. Store Configuration parameters.
`
`
`
`Select Optimal bearer for the application flow based On
`QoS using s a dynamic reservation approach (reserve
`resOUrces like radio channels) in advance for bearer
`selected Or a differentiated Services approach (packet-by-packet)
`
`
`
`176
`
`178
`
`For Subsequent application flows, use stored parameterSto
`performan abbreviated authentication and configuration
`withOut Contacting an external network entity.
`
`18O
`
`
`
`
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 12 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 11 of 12
`
`US 6,608,832 B2
`
`Fig. 12
`SGSN
`
`MSC/DAU
`
`GGSN/AS
`
`RADIUS
`SerWer
`
`GTP (DHCPDISCOVER
`
`GGSN maps the DHCP
`Authentication Request to
`a RADIUS Request by
`Selecting RADIUS Server
`based On USerld.
`
`
`
`RADIUS ACCess
`ReGuest
`{UserName, User
`Password...)
`RADIUS ACCeSS
`ACCept
`{Result Code,
`Configuration info)
`
`PDP Context is activated,
`MS starts DHCP procedure
`A logical relationship to
`a GGSN is established.
`
`MSC/DAU
`terminates the modem
`COnnection. It Selects
`LEast Egon
`S. data
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`GGSN stores the triplet
`PaSSWOrd, Userld and MSid.
`Based On Result Code and
`Configuration information, the
`GGSN can proceed with the
`DHCP host Configuration
`procedure
`L2TP(PPP CHAP/PAP
`Request
`{MSid, Userd, Password.
`
`
`
`GGSN gets a
`L2TP tunneled
`PPP request for
`a CS Call. GGSN
`matches the
`provided triplet
`With stored
`information and
`reSDOnds
`WithOut
`generatin
`a new RADIUS
`ACCeSS Request.
`
`L2TP(PPP CHAP/PAP
`ReSDOnSe
`Result COde...
`
`MS-SPAuthentication for CS and PS Services
`
`Ex.1011
`APPLE INC. / Page 13 of 28
`
`

`

`U.S. Patent
`
`Aug. 19, 2003
`
`Sheet 12 of 12
`
`US 6,608,832 B2
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Fig. 13
`MSC/DAU s
`
`GGSN/AS
`
`
`
`PDPCOntext is activated.
`A logical link to a GGSN is
`established. MS Starts
`DHCP Configuration
`procedure.
`
`
`
`GTP (DHCPDISCOVER
`{Tid=MSid + NSAPI.}
`Because RADIUS Authent
`cation has been performed
`the DHCP Configuration
`Continues. Agent Remote
`ld and giaddrfields are
`added to the DHCP
`DISCOVER meSSace.
`GGSN checks incoming
`and Outgoing tunnel
`identifier when relaying
`the DHCP
`OFFER towards the MS.
`
`gadgent Remoted:
`
`UDP(DHCP OFFER
`(lease time, DHCP
`Server ID, yiaddr)
`
`Multiple DHCP OFFERs
`may be received. MS
`Selects One.
`
`(TID, lease time, DHCP
`Server ID, yiaddr...}
`
`
`
`GTP (DHCP REQUEST
`
`GGSN stores IP
`address allocated to
`MS along with MSid.
`
`{giaddr, Agent
`Remoteld.}
`UDP(DHCPACK
`{yiaddr, Result Code...}
`
`MS initiates a PPP Session
`OVer GSMCS bearer Service
`
`{MSid, Default
`Configuration...}
`
`
`
`L2TP(PPP Configure-Ack
`{MSid, Result Code...)
`
`GGSN matches
`PPP request With
`Stored DHCP
`COnfiguration data
`and returns ac
`knowledgement.
`No Configuration
`with ISP required.
`
`IPHost Configuration for CS and PSBearer Services,
`
`
`
`
`
`
`
`Ex.1011
`APPLE INC. / Page 14 of 28
`
`

`

`US 6,608,832 B2
`
`1
`COMMON ACCESS BETWEEN A MOBILE
`COMMUNICATIONS NETWORKAND AN
`EXTERNAL NETWORK WITH SELECTABLE
`PACKET-SWITCHED AND CIRCUIT.
`SWITCHED AND CIRCUIT-SWITCHED
`SERVICES
`
`RELATED APPLICATION
`This application claims priority from U.S. Provisional
`Patent Application Ser. No. 60/060,061 filed Sep. 25, 1997.
`This application is also related to commonly-assigned U.S.
`patent application Ser. No. 09/087,496 filed May 29, 1998,
`the disclosure of which is incorporated by reference.
`
`FIELD OF THE INVENTION
`The present invention relates to mobile communications,
`and more particularly, to different Services and features that
`may be employed to establish and enhance communications
`between a mobile Station in a mobile communications
`network and an external network entity.
`
`15
`
`2
`network. Another is the Cellular Digital Packet Data
`(CDPD) network used into the existing D-AMPS network.
`A significant interest of end users of a mobile packet data
`service such as GPRS is that wireless PCs support conven
`tional Internet-based applications like file transfer, Submis
`Sion and reception of e-mail, and "Surfing the Internet via
`the worldwide web. Conferencing and playback
`applications, including Video and multimedia, are also
`important Services to be Supported by mobile networks.
`Although circuit-Switched Services are well known in
`mobile networks, mobile packet-Switched Services are quite
`new. Therefore, a brief description of the latter using GSM/
`GPRS as an example is now provided.
`FIG. 1 shows a mobile data service from a user's point of
`view in the context of a mobile communications system 10.
`An end user communicates data packets using a mobile host
`12 including for example a laptop computer 14 connected to
`a mobile terminal 16. The mobile host 12 communicates for
`example with a fixed computer terminal 18 incorporated in
`a local area network (LAN) 20 through a mobile packet data
`Support node 22 via one or more routerS 24, a packet data
`network 26, and a router 28 in the local area network 20. Of
`course, those skilled in the art will appreciate that this
`drawing is simplified in that the “path’ is a logical path
`rather than an actual physical path or connection. In a
`connectionless data packet communication between the
`mobile host 12 and fixed terminal 18, packets are routed
`from the Source to the destination independently and do not
`necessarily follow the same path (although they can).
`Thus, independent packet routing and transfer within the
`mobile network is Supported by a mobile packet data Support
`node 22 which acts as a logical interface or gateway to
`external packet networks. A Subscriber may send and receive
`data in an end-to-end packet transfer mode without using
`any circuit-Switched mode network resources. Moreover,
`multiple point-to-point, parallel applications are possible.
`For example, a mobile host like a mobile PC might run at the
`Same time a Video conference application, an e-mail
`application, a facsimile application, a web browsing
`application, etc. The Video conference application would
`typically require more than one data stream (hereafter
`referred to as an application flow).
`FIG. 2 shows a more detailed mobile communications
`System using the example GSM mobile communications
`model that Supports both circuit-Switched and packet
`Switched communications and includes a circuit-Switched
`network 35 and a packet-switched network 51. A mobile
`host 12 including a computer terminal 14 and mobile radio
`16 communicates over a radio interface with one or more
`base stations (BSS) 32. Each base station 32 is located in a
`corresponding cell 30. Multiple base stations 32 are con
`nected to a base station controller (BSC) 34 which manages
`the allocation and deallocation of radio resources and con
`trols handovers of mobile stations from one base station to
`another. A base Station controller and its associated base
`Stations are Sometimes referred to as a base Station Sub
`system (BSS). The BSC 34 is connected to a mobile
`switching center (MSC) 36 in the GSM circuit-switched
`network 35 through which circuit-switched connections are
`set up with other networks 38 such as the Public Switched
`Telephone Network (PSTN), Integrated Services Digital
`Network (ISDN), etc.
`The MSC 36 is also connected via a Signaling System
`Number 7 (SS7) network 40 to a Home Location Register
`(HLR) 42, a Visitor Location Register (VLR) 44, and
`Authentication Center (AUC) 46. The VLR 44 includes a
`
`BACKGROUND AND SUMMARY OF THE
`INVENTION
`The main application of most mobile radio Systems like
`the Global System for Mobile communications (GSM) has
`been mobile telephony which typically only Supports circuit
`Switched communications where guaranteed, “fixed” cir
`cuits are dedicated to a user for the duration of a call.
`However, packet-Switched applications, like facsimile trans
`mission and short message exchange, are becoming popular
`in mobile networks. Example data applications include
`wireleSS personal computers, mobile offices, electronic
`funds transfer, road transport telemetry, field Service
`businesses, fleet management, etc. These data applications
`are characterized by “bursty’ traffic where a relatively large
`amount of data is transmitted over a relatively short time
`interval followed by significant time intervals when little or
`no data is transmitted.
`While bursty traffic can be transmit using a circuit
`Switched channel, Such a transmission underutilizes that
`channel because there are likely large intervals between
`bursts when the channel is reserved but is not being used,
`there is no information to be transmit from or received by the
`user. From an efficiency view point, this is a waste of
`transmission resources which are particularly limited for
`radio communications. However, from a customer Service
`View point, because a circuit-Switched channel is not shared
`with other users, the user is essentially guaranteed a certain
`quality of Service. In addition to inefficiency, it takes a
`relatively long time to Set up and take down a circuit
`Switched call compared with individual packet routing in
`packet-Switched Sessions. In bursty traffic Situations, packet
`Switched bearers better utilize the transmission bandwidth
`because a communications resource is used only when there
`is data to transmit. Communication channels are therefore
`typically shared by many users. Another advantage is that in
`contrast to time-oriented charging applied for circuit
`Switched connections, packet-Switched data Services allow
`charging depending on the amount of data actually trans
`mitted and on the quality of Service of that transmission.
`In order to provide Such mobile data applications, packet
`radio network Services accommodate connectionless,
`packet-switched data services with high bandwidth effi
`ciency. One example is the General Packet Radio Service
`(GPRS) incorporated into the existing circuit-switched GSM
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Ex.1011
`APPLE INC. / Page 15 of 28
`
`

`

`US 6,608,832 B2
`
`15
`
`25
`
`35
`
`40
`
`3
`database containing the information about all mobile Sta
`tions currently located in a corresponding location or Service
`area as well as temporary Subscriber information needed by
`the MSC to provide services to mobiles in its service area.
`Typically, when a mobile Station enters a visiting network or
`Service area, the corresponding VLR 44 requests and
`receives data about the roaming mobile Station from the
`mobile's HLR and stores it. As a result, when the visiting
`mobile station is involved in a call, the VLR 44 already has
`the information needed for call Setup.
`The HLR 42 is a database node that Stores and manages
`subscriptions. For each “home” mobile subscriber, the HLR
`contains permanent Subscriber data Such as the mobile
`station ISDN number (MSISDN) which uniquely identifies
`the mobile telephone subscription in the PSTN numbering
`plan and an international mobile subscriber identity (IMSI)
`which is a unique identity allocated to each Subscriber and
`used for Signaling in the mobile networks. All network
`related Subscriber information is connected to the IMSI. The
`HLR 42 also contains a list of Services which a mobile
`Subscriber is authorized to use along with a current Sub
`Scriber location number corresponding to the address of the
`VLR currently serving the mobile subscriber.
`Each BSC 34 also connects to the GSM packet-switched
`network corresponding to GPRS network 51 at a Serving
`GPRS Support Node (SGSN) 50 responsible for delivery of
`packets to the mobile Stations within its Service area. The
`gateway GPRS Support node (GGSN) 54 acts as a logical
`interface to external data packet networkS Such as the IP data
`network 56. SGSN nodes 50 and GGSN nodes 54 are
`connected by an intra-PLMN IP backbone 52. Thus,
`between the SGSN 50 and the GGSN 54, the Internet
`protocol (IP) is used as the backbone to transfer data
`packets.
`Within the GPRS network 51, packets or protocol data
`units (PDUs) are encapsulated at an originating GPRS
`support node and decapsulated at the destination GPRS
`Support node. This encapsulation/decapsulation at the IP
`level between the SGSN 50 and the GGSN 54 is called
`“tunneling” in GPRS. The GGSN 54 maintains routing
`information used to “tunnel PDUs to the SGSN 50 cur
`rently serving the mobile station. A common GPRS Tunnel
`Protocol (GTP) enables different underlying packet data
`protocols to be employed even if those protocols are not
`supported by all of the SGSNs. All GPRS user-related data
`needed by the SGSN to perform routing and data transfer
`functions is accessed from the HLR 42 via the SS7 network
`40. The HLR 42 stores routing information and maps the
`IMSI to one or more packet data protocol (PDP) addresses
`as well as mapping each PDP address to one or more
`GGSNS.
`Before a mobile host can Send packet data to an external
`network like an Internet service provider (ISP) 58 shown in
`FIG. 2, the mobile host 12 has to (1) “attach” to the GPRS
`network 51 to make its presence known and (2) create a
`packet data protocol (PDP) context to establish a relation
`ship with a GGSN 54 towards the external network that the
`mobile host is accessing. The attach procedure is carried out
`between the mobile host 12 and the SGSN 50 to establish a
`logical link. As a result, a temporary logical link identity is
`assigned to the mobile host 12. APDP context is established
`between the mobile host and the GGSN 54. The selection of
`a GGSN 54 is based on the name of the external network to
`be reached.
`One or more application flows (sometimes called “routing
`contexts”) may be established for a single PDP context
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`through negotiations with the GGSN 54. An application flow
`corresponds to a stream of data packets distinguishable as
`being associated with a particular host application. An
`example application flow is an electronic mail message from
`the mobile host to a fixed terminal. Another example appli
`cation flow is a downloaded graphics file from a web site.
`Both of these application flows are associated with the same
`mobile host and the same PDP context.
`Packet-Switched data communications are based on Spe
`cific protocol procedures which are typically Separated into
`different layers. FIG. 3A shows a GPRS “transmission
`plane' that is modeled with multi-layer protocol StackS.
`Between the GGSN and the SGSN, the GPRS tunneling
`protocol (GTP) tunnels the PDUs through the GPRS back
`bone network 52 by adding routing information to encap
`sulate PDUs. The GTP header contains a tunnel end point
`identifier (TID) for point-to-point and multicast packets as
`well as a group identity (GID) for point-to-multipoint pack
`ets. Additionally, a type field that specifies the PDU type and
`a quality of service profile associated with a PDP context
`session is included. Below the GTP, the well-known Trans
`mission Control Protocol/User Diagram Protocol (TCP/
`UDP) and Internet Protocol (IP) are used as the GPRS
`backbone network layer protocols. Ethernet, frame relay
`(FR), or asynchronous transfer mode (ATM)-based proto
`cols may be used for the link and physical layerS depending
`on the operator's network architecture.
`Between the SGSN and mobile station/host, a SubNet
`work Dependent Convergence Protocol (SNDCP) maps
`network level protocol characteristics onto the underlying
`logical link control (LLC) and provides functionalities like
`multiplexing of network layer messages onto a single virtual
`logical connection, ciphering, Segmentation, and compres
`sion. A Base Station System GPRS Protocol (BSSGP) is a
`flow control protocol, which allows the base Station System
`to start and stop PDUs sent by the SGSN. This ensures that
`the BSS is not flooded by packets in case the radio link
`capacity is reduced, e.g., because of fading and other
`adverse conditions. Routing and quality of Service informa
`tion are also conveyed. Frame relay and ATM may be used
`to relay frames of PDUs over the physical layer.
`Radio communication between the mobile Station and the
`GPRS network covers physical and data link layer function
`ality. The physical layer is split up into a physical link
`sublayer (PLL) and a physical RF Sublayer (RFL). RFL
`performs modulation and demodulation of the physical
`waveforms and Specifies carrier frequencies, radio channel
`Structures, and raw channel data rates. PLL provides Services
`for information transfer over the physical radio channel and
`includes data unit framing, data coding, and detection/
`correction of physical medium transmission areas. The data
`link layer is Separated into two distinct Sublayers. The radio
`link control/medium access control (RLC/MAC) sublayer
`arbitrates access to the shared physical radio medium
`between multiple mobile stations and the GPRS network.
`RLC/MAC multiplexes data and Signaling information, per
`forms contention resolution, quality of Service control, and
`error handling. The logical link control (LLC) layer operates
`above the MAC layer and provides a logical link between
`the mobile host and the SGSN.
`It is important to be able to provide a certain particular
`communications Service with a requested quality. For
`example, certain multimedia applications or even a simple
`Voice phone call need guarantees about accuracy,
`dependability, and Speed of transmission. In packet
`switched communications, “best efforts” are usually
`employed, and no special attention is paid to delay or
`
`Ex.1011
`APPLE INC. / Page 16 of 28
`
`

`

`15
`
`S
`throughput guarantees. Generally, quality of Service param
`eters can be characterized qualitatively in three Services
`classes including deterministic (used for hard, real-time
`application), Statistical (used for Soft real-time applications),
`and best effort (everything else where no guarantees are
`made). Quantitative parameters may include throughput
`(Such as the average data rate or peak data rate), reliability,
`delay, and jitter corresponding to the variation delay
`between a minimum and maximum delay time that a mes
`Sage experiences.
`In the context of providing quality of Service (QoS) in a
`mobile data communications Systems, one QoS approach is
`to assign a specific priority to each PDP context. But this
`approach is unsatisfactory. AS explained above, each PDP
`context may have plural application flows, and each appli
`cation flow may have different needs. For example, real time
`applications like telephony require a guaranteed, low delay
`Service while image Video needs a predictable delay Service.
`More Specifically, elastic applications like interactive bursts,
`interactive bulk transfer, and asynchronous bulk transfer
`require different degrees of best effort or as Soon as possible
`delay Service.
`It is an important objective of the present invention to
`provide quality of Service based, radio Internet access in
`order to Support multiple application Services including
`Voice, data, and multimedia, where Some of the applications
`may have plural application flows operating Simultaneously.
`In the case of Internet integrated Services, important quality
`of Service factors are perceived transport link layer delay,
`jitter, bandwidth, and reliability. Rather than limiting the
`quality of Service to a single PDP context, the present
`invention defines a quality of Service for each individual
`application flow as is described below and in the above
`identified patent application. In addition, the present inven
`tion permits Selection of a particular type of transfer mecha
`nism that is best Suited to transfer the individual application
`flow in accordance with its quality of Service requirements.
`Normally a network technology transferS data only
`according to one type of transfer mechanism—either circuit
`Switched or packet-switched-even in the GSM which
`includes both a circuit-Switched and a packet-Switched net
`work Sharing the same radio acceSS interface. In the present
`invention an optimal type of mobile communications net
`work transfer Service-a circuit-Switched transfer Service or
`a packet-Switched transfer Service-is specified on an indi
`vidual application flow basis. Circuit-Switched Services may
`be selected, for example, for real time (low delay and Small
`jitter) application flows like audio and Video. Packet
`Switched bearers may be selected for non-real time, Internet
`type data applications Such as Surfing on the Worldwide web,
`file transfer, e-mail, and telnet, all of which require fast
`channel acceSS and bursty data transfer capability.
`Initially a mobile station registers with the mobile com
`munications network to establish communication with an
`external network entity Such as an Internet Service provider
`(ISP). During that communication, an application may ini
`tiate different data Streams or flows of an application
`(hereafter referred to as application flows) between the
`mobile station and the external network entity. For each
`application flow, a determination is made whether a circuit
`Switched or a packet-switched bearer should be established.
`A bearer “bears' or carries information from the mobile
`Station through the mobile communications network
`towards the external network entity and carries information
`from the external network entity through the mobile com
`munications network to the mobile Station.
`65
`Each application flow may have a corresponding quality
`of Service request. Based on that corresponding quality of
`
`45
`
`50
`
`55
`
`60
`
`US 6,608,832 B2
`
`25
`
`35
`
`40
`
`6
`Service, a determination is made whether a circuit-Switched
`bearer or a packet-Switched bearer is better Suited to trans
`port the application flow. The quality of Service parameters
`Specified by the application for an individual application
`flow are mapped to corresponding quality of Service param
`eters for the Selected one of the circuit-Switched or packet
`Switched bearers. Mobile communication resources for the
`Selected bearer and corresponding quality of Service param
`eters may be reserved in advance for each application flow
`(the resource reservation approach). Alternatively, the
`header of each information packet in an application flow
`may specify a generally recog