(12) United States Patent
`Burgaleta Salinas et al.
`
`USOO6469998B1
`(10) Patent No.:
`US 6,469,998 B1
`(45) Date of Patent:
`Oct. 22, 2002
`
`(54) METHOD AND APPARATUS FOR
`COMMUNICATING DATA PACKETS FROM
`AN EXTERNAL PACKET NETWORK TO A
`MOBILE RADIO STATION
`
`(75) Inventors: Alberto Burgaleta Salinas, Alcorcón;
`Miguel Cobo Esteban, Madrid, both of
`(ES); Thorsten Herber, Kista (SE)
`(73) Assignee: Telefonaktiebolaget LM Ericsson
`
`OTHER PUBLICATIONS
`“Dynamic Host Configuration Protocol, R. Droms, Oct.
`1993, pp. 1-34.*
`C. Perkins, Oct. 1996, “IP Mobility Support", pp. 1-79.*
`sk -
`cited by examiner
`Primary Examiner Dang Ton
`(74) Attorney, Agent, or Firm Nixon & Vanderhye, P.C.
`
`(*) Notice:
`
`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.: 09/166,778
`(22) Filed:
`Oct. 6, 1998
`(51) Int. Cl.................................................... H04J 3/16
`(52) U.S. Cl. ........................................ 370338,37046s
`(58) Field of Search ................................. 370,351, s2,
`370/389, 395, 401, 400, 402, 403, 480
`465 33s. 3 41. 3 49. 42s. 46s. 337 347.
`346,345, 350; 455/422, 450, 452, 453,
`428,560.554
`s a s/ Yus
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`5,159,592 A 10/1992 Perkins
`5,708.655 A
`1/1998 Toth et al.
`
`FOREIGN PATENT DOCUMENTS
`WO 97/21313
`6/1997
`WO 97/48246
`12/1997
`WO 99/21379
`4/1999
`
`WO
`WO
`WO
`
`Packet data are efficiently communicated from a packet data
`network to a mobile subscriber by way of a mobile com
`munications network. When the mobile communications
`network receives a message from the packet data network
`intended for the mobile Subscriber, an available mobile
`communications network packet address is dynamically
`assigned from a pool of packet addresses to the mobile
`subscriber. Thereafter, packets included in the data message
`s s the ".
`E. using that yay,
`allocated address. When the address is no longer needed, it
`is returned to the pool. Each packet address in the pool
`includes a corresponding indication that designates whether
`that address is allocated or available for allocation. A cor
`respondence is established between a name associated with
`the mobile Subscriber (e.g., an Internet domain name), and
`a mobile subscriber identifier (e.g., an IMSI). A
`dynamically-assigned packet address is associated with the
`corresponding mobile Subscriber name and identifier.
`Thereafter, packet data from the packet data network that
`include the mobile station name are directed to the mobile
`Subscriber using the corresponding mobile Subscriber iden
`tifier and the associated, dynamically-allocated packet
`address.
`
`32 Claims, 10 Drawing Sheets
`
`
`
`Packet Data
`Support Node
`
`
`
`
`
`Packet Data
`NetWOrk
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`Ex.1028 / IPR2022-01222 / Page 1 of 18
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 1 of 10
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`US 6,469,998 B1
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`
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`s
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`CS
`N4
`On 5
`as a
`59 2.
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`n
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`U.S. Patent
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`Oct. 22, 2002
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`Sheet 2 of 10
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`US 6,469,998 B1
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`U.S. Patent
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`Oct. 22, 2002
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`Sheet 3 of 10
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`US 6,469,998 B1
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`V9
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`Ex.1028 / IPR2022-01222 / Page 5 of 18
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 5 of 10
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`US 6,469,998 B1
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`Fig. 4
`
`DYNAMIC ADDRESS
`
`100
`
`102
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`104
`
`106
`
`108
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`
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`
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`
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`Detect a data message from a packet
`network to a mobile SubSCriber
`
`Dynamically assign an available mobile network
`packet address to the mobile subscriber
`
`Route packets in the data message based on a domain
`name from the packet network to the mobile subscriber
`using the dynamically-assigned packet address
`
`Return dynamically-assi E. packet address
`pool when mobile Su SCriber detaches
`
`
`
`CONTINUE
`
`Ex.1028 / IPR2022-01222 / Page 6 of 18
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 6 of 10
`
`US 6,469,998 B1
`
`Fig. 5
`
`
`
`88
`
`Static Relationship
`
`Static or non-static
`relationship
`PDP Address allocated
`
`MS
`
`PDP address 1
`PDP address 2
`PDP address 3
`PDP address 4
`PDP address 5
`
`PDP address in
`
`Dynamic PDP address
`
`Allocation indication
`
`dynamic PDP address 1
`dynamic PDP address 2
`dynamic PDP address 3
`dynamic PDP address 4
`
`dynamic PDP address in
`
`allocated
`allocated
`idle
`allocated
`
`idle
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`Ex.1028 / IPR2022-01222 / Page 7 of 18
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 7 of 10
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`US 6,469,998 B1
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`Fig. 7
`
`120
`
`DN/PDPADDRESSRELATIONSHIPS
`
`Establish a relationship (e.g., Table 1) between a domain name of
`a mobile SubScriber (e.g., e-mail address) and an
`identification of the mobile subscriber (e.g., IMSI)
`
`Establish and maintain (also in Table 1) recording what PDP/IP
`address (if any) is allocated to each domain name/mobile ID pair
`
`Establish and maintain list of dynamic PDP/IP addresses (e.g. Table 2) with
`their current availability status
`
`RETURN
`
`
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 8 of 10
`
`US 6,469,998 B1
`
`Fig. 8
`
`140
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`DYNAMIC PDPADDRESS ALLOCATION
`
`
`
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`
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`
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`Receive a packet message at DNSS in mobile packet network
`having an associated domain name
`
`DNSS checks Table 1 to See if it has that domain name defined
`
`If there is a static PDP address assigned in Table 1,
`send back that address to originating node via PDN
`
`146
`
`148
`
`Otherwise, assign an available dynamic PDP address from Table 2
`to be domain name/mobile ID pair. Send that PDP address to
`the originating node via PDN (and possibly to other nodes,
`e.g., HLR, SGSN, etc.)
`
`RETURN
`
`Ex.1028 / IPR2022-01222 / Page 9 of 18
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 9 of 10
`
`US 6,469,998 B1
`
`
`
`C d
`
`1. DNS query
`
`2. ppp
`address
`request
`-C
`
`Determination of a
`temporary PDP address
`
`3. PDP
`address
`to IMS
`-C m
`
`4. PDP
`address
`to IMSlack 5. PDP
`H D- address
`response
`ID
`
`6. DNS
`response
`
`7. PDP
`PDU
`
`8. R
`Houting
`info for
`GPRS
`Request
`9. Send
`Routing
`info for
`GPRS
`Respons
`
`10. PDU Notification Request
`
`11. PDU Notification Response
`
`12, Request PDP Context Activation
`
`13. PDP Context Activation procedure
`
`Fig. 9
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`U.S. Patent
`
`Oct. 22, 2002
`
`Sheet 10 Of 10
`
`US 6,469,998 B1
`
`1. Delete PDP Context Request
`
`2. Delete PDP Context Response
`
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`3. PDP address
`return request
`
`
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`Return PDP address
`
`4. PDP address
`return ack
`
`
`
`-
`
`m
`
`Fig. 10
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`US 6,469,998 B1
`
`1
`METHOD AND APPARATUS FOR
`COMMUNICATING DATA PACKETS FROM
`AN EXTERNAL PACKET NETWORK TO A
`MOBILE RADIO STATION
`
`FIELD OF THE INVENTION
`The present invention relates to packet communications in
`a mobile communications network, and more particularly, to
`dynamically providing packet addresses to mobile Stations
`So that packets received from an external packet network can
`be routed to that mobile station.
`
`2
`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 Station
`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-services
`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
`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.
`
`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
`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.
`
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`US 6,469,998 B1
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`3
`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 PLMN 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 packet data networks 56 Such as the IP
`data network 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. A Subscriber/Service management
`system 60 is connected to the GGSN 54 and the HLR 42 to
`update mobile Subscriber information and packet address
`information. The GGSN 54 is also coupled to the HLR 42 to
`update Subscriber database information including assigned
`packet addresses.
`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 used. All GPRS user-related data needed by
`the SGSN to perform routing and data transfer functions is
`40
`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
`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.
`
`4
`In order to communicate a packet of data to a wireleSS
`communications Station requires that the packet be
`addressed with an identification address of the mobile sta
`tion. An Internet Protocol (IP) address is an example of such
`an identification address which can be used to address
`packets of data which are to be routed to the communica
`tions Station. An IP address is used when transmissions are
`made pursuant to an Internet protocol. Analogous addresses
`are used when data is to be transmitted pursuant to other
`protocols Such as the X.25 protocol.
`Typically, packet data transmissions to a mobile Station
`occur only Seldomly and during only Short intervals. For
`instance, messaging Services typically utilize Storage units
`which Store the message and information prior to commu
`nication of Such information to the mobile station. The
`mobile Station need not be reachable at a particular time for
`the messaging information to be communicated to the
`mobile Station. The message originator need only be cog
`nizant of the message address, e.g., the mail address, of the
`mobile Station. Once Stored at the message Storage unit, the
`mobile Station may retrieve anytime thereafter the messages
`from the Storage unit.
`This and most other data packet Services do not require
`that a mobile Station be identified with a permanent packet
`address. Commonly-assigned U.S. Pat. No. 5,708,655 to
`Toth et al. describes in the GSM/GPRS network providing
`a temporary packet address, e.g., an IP address, after a
`mobile station has successfully attached to the GPRS net
`work. After Successful attachment, a temporary packet
`address is assigned to a mobile Station So that it can Send
`packetS-Sometimes referred to as “mobile-originated”
`packets-to another communications node. Of course,
`mobile-originated packets may originate from a terminal
`coupled to the mobile station. However, the Toth patent does
`not address the problem of routing the packets to a mobile
`station when the mobile data network receives “mobile
`terminating” packets for a GSM/GPRS mobile subscriber.
`Again, "mobile-terminating packets may terminate at the
`mobile Station or at a terminal device coupled to the mobile
`Station. Specifically, the Toth patent does not make a pro
`Vision for assigning a dynamic packet address when receiv
`ing terminating packets for a mobile Subscriber.
`Recent proposals to the GSM/GPRS specification offer a
`Static addressing Scheme for handling mobile-terminating
`packets in the GSM/GPRS systems. Static addressing is
`undesirable because there is only a finite number of packet
`type addresses that can be administered and allocated by a
`mobile communications network. Consequently, System
`capacity is limited by the number of Static addresses. Static
`addressing is also inefficient. Many if not most of Statically
`assigned addresses to mobile Subscribers would not be
`utilized much of the time.
`Another obstacle with data packet communications in
`mobile communications networks is that no mechanism is in
`place for routing mobile-terminating packets based on the
`mobile Subscriber’s “domain name.” Unlike an IP address,
`Such as a 32-bit integer used to identify a particular machine,
`users prefer to assign machines pronounceable, easily
`remembered names. A domain name System provides a
`Scheme for assigning meaningful, high-level names to a
`large Set of machines and provides a mechanism for map
`ping between high-level machine names and IP addresses
`including translation from high-level names to IP addresses
`and translation from IP addresses to high-level machine
`names. Typically, a domain name may consist of a Sequence
`of Subnames Separated by a delimiter character the period.
`Individual Sections of the name might represent Sites or
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`25
`
`S
`groups but the domain System simply refers to each Section
`as a label. An example of Such a domain name is an Internet
`e-mail address Such as XXXGericSSon.se. In addition to the
`rules for name Syntax, the domain name Scheme includes a
`distributed System for mapping names to addresses. The
`mechanism for mapping names to addresses consists of
`independent, cooperative name Servers that Supply name
`to-address translation mapping from domain names to IP
`addresses. To perform domain name resolution, the “client'
`Sends a domain name query that contains the name to be
`resolved to a name server for resolution. When the domain
`name Server receives the query, it checks to See if the name
`lies in the subdomain for which it is an authority. If so, it
`translates the name to an address according to its database
`and appends an answer to the query before Sending it back
`to the client.
`The problem with Such a domain name query System in a
`mobile data communications environment is that to imple
`ment dynamic addressing, the mobile data communication
`network should be able to associate this dynamic IP address
`to the proper mobile subscriber identified in the mobile
`network via the IMSI or MSISDN. Today, no such associa
`tion or a mechanism to make Such an association are defined
`or provided.
`It is an object of the present invention to overcome the
`above-described obstacles by providing a method and appa
`ratus for efficiently routing terminating data packets to a
`specific mobile subscriber.
`It is another object of the present invention to dynamically
`allocate temporary packet addresses to mobile Stations. So
`that they can receive packets.
`It is another object of the present invention to route
`terminating packets to a mobile Subscriber based on that
`Subscriber's Internet destination or domain name.
`It is an object of the present invention to provide a pool
`of packet addresses in a mobile communications network
`that can be shared and efficiently allocated to many mobile
`Subscribers.
`These and other objects are achieved by the present
`40
`invention which provides a method for efficiently commu
`nicating packet data from a packet data network to a mobile
`Station by way of a mobile communications network. The
`present invention seeks to efficiently pool mobile
`terminating packet addresses, dynamically allocate them on
`an as-needed basis, and return those temporary addresses to
`the pool when they are no longer needed. When the mobile
`communications network receives a message from the
`packet data network intended for the mobile Station, an
`available mobile communications network packet address is
`dynamically assigned from the pool of packet addresses to
`the mobile Station. Thereafter, packets included in the data
`message are routed to the mobile Station using that
`dynamically-assigned packet address. When the address is
`no longer needed, it is returned to the pool. Each packet
`address in the pool includes a corresponding indication that
`designates whether that address is allocated or available for
`allocation.
`In a preferred example embodiment, a correspondence is
`established between a Subscriber identification name oralias
`(e.g., Internet or domain name) associated with the mobile
`subscriber and a mobile Subscriber identifier. Preferably, the
`mobile identifier is an international mobile Subscriber iden
`tifier (IMSI). In addition, a dynamically-assigned packet
`address is associated with the corresponding mobile Sub
`Scriber name and identifier. Thereafter, packets from the
`packet data network associated with the dynamic IP address
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`allocated for this data communication are directed to the
`mobile Subscriber using the corresponding assigned packet
`address.
`The mobile communications network includes a gateway
`Service node that is associated with a mobile Station as well
`as with an external packet data network. The mobile com
`munications network includes a mobile packet-Switched
`network, coupled to the radio base Station, that includes a
`domain name System server associated with the gateway
`Service node. In one embodiment, the domain name System
`Server may be located in the gateway node, and in another
`embodiment, the domain name System Server is coupled to
`but located outside of the gateway node. The domain name
`System server receives a domain name Service query from
`the external packet data network that includes a domain
`name corresponding to the mobile Subscriber. A dynamic
`packet address controller receives a request for a packet
`address from the domain name System server, assigns a
`temporary packet address to the mobile Subscriber, and
`provides that temporary packet address to the domain name
`System server. In a preferred embodiment, the dynamic
`packet address controller is located in the gateway node. The
`domain name System Server then returns the temporary
`address to the external packet network in response to the
`domain name Service query. Once a temporary packet
`address is assigned, the gateway controller initiates a data
`Session with the mobile Station and routes terminating
`packets to the mobile Station using the temporary packet
`address.
`The dynamic packet address controller includes a memory
`that Stores a first list that establishes correspondences
`between domain names associated with mobile Subscribers
`via mobile Subscriber identifiers, and associated packet
`addresses. The dynamic packet address controller also stores
`a Second list corresponding to the pool of dynamically
`assignable packet addresses, each address having a current
`Status indicator. The dynamic packet address controller
`assigns as temporary addresses those dynamically
`assignable packet addresses in the Second electronic list
`having an “available' current status indicator. Whenever the
`packet address is allocated or deallocated, the dynamic
`packet address controller changes the State of the corre
`sponding Status indicator in the Second list. The first list may
`Store one or more different domain names associated with
`the mobile Subscriber in accordance with the same mobile
`subscriber identifier but with a different temporary packet
`address for each of the different domain names. Different
`domain names may be used for example when the mobile
`Station is running different applications Such as e-mail, web
`browsing, Video conferencing, etc.
`From the Standpoint of the external packet network, no
`Special procedures need to be performed in order to route
`terminating packets to a mobile Station. Standard domain
`name Service protocols which are widely used throughout
`the Internet are all that is necessary. Thus, Simply by
`detecting the mobile Subscriber's domain name, associated
`protocol data units are directed to the mobile Subscriber
`using the dynamic packet address which is associated by the
`dynamic packet address controller with a mobile Subscriber
`identifier and a domain name.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`The foregoing and other objects, features, and advantages
`of the invention will be apparent from the following descrip
`tion of preferred embodiments as illustrated in the accom
`panying drawings in which reference characters refer to the
`
`Ex.1028 / IPR2022-01222 / Page 14 of 18
`Apple Inc. v. Smart Mobile Technologies LLC
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`Same parts throughout the various views. The drawings are
`not necessarily to Scale with emphasis being placed upon
`illustrating the principles of the invention.
`FIG. 1 is a simplified diagram showing a data communi
`cation between a mobile host and a fixed host;
`FIG. 2 is a more detailed diagram showing a GSM mobile
`communications System including a General Packet Radio
`Service (GPRS) data network;
`FIG. 3A is a function block diagram illustrating a gateway
`node of a mobile packet-Switched network in a mobile
`communications System in accordance with one example
`embodiment of the present invention;
`FIG. 3B is a function block diagram illustrating a gateway
`node of a mobile packet-Switched network in a mobile
`communications System in accordance with a Second
`example embodiment of the present invention;
`FIG. 4 is a flowchart diagram illustrating a Set of dynamic
`address procedures in accordance with an example embodi
`ment of the present invention;
`FIG. 5 is a table illustrating a relationship between a
`mobile Subscriber (e.g., Internet or domain) name, a mobile
`Subscriber identifier (e.g., IMSI), and an allocated packet
`address (e.g., PDP address);
`FIG. 6 is a table illustrating a relationship between
`dynamically-assignable packet addresses and an indication
`of allocation status (allocated/idle);
`FIG. 7 is a flowchart diagram illustrating example pro
`cedures for establishing relationships between mobile Sub
`Scriber names and packet addresses;
`FIG. 8 is a flowchart diagram illustrating example pro
`cedures for dynamically allocating addresses from the rela
`tionships established in FIG. 7;
`FIG. 9 is a Signaling flow diagram for an example
`implementation of the present invention in the context of a
`GSM/GPRS mobile communications system illustrating
`example Signals employed to effect a mobile terminating
`data communication in which a packet address is tempo
`rarily allocated to a mobile Subscriber in order to commu
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`nicate the terminating packets to the mobile Subscriber; and
`FIG. 10 is a Signaling flow diagram in the context of a
`GSM/GPRS mobile communications system showing
`example procedures in which a previously allocated packet
`address is returned to the pool of dynamically-assignable
`packet addresses.
`DETAILED DESCRIPTION OF THE DRAWINGS
`In the following description, for purposes of explanation
`and not limitation, Specific details are Set forth, Such as
`particular embodiments, hardware, techniques, etc. in order
`to provide a thorough understanding of the invention.
`However, it will be apparent to one skilled in the art that the
`present invention may be practiced in other embodiments
`that depart from these specific details. For example, while a
`Specific example embodiment of the present invention is
`described in the context of a GSM/GPRS cellular telephone
`network, those skilled in the art will appreciate that